PinoyDVD: The Pinoy Digital Video & Devices Community
Home Theater => Audio => Amplifier => Topic started by: allan1836 on Feb 26, 2007 at 04:17 PM
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I'm in the process of putting up a new project which involves a hybrid audio set-up. I'm planning to match a tube pre-amp to a ss power amp. My question is, does all power amp with similar power rating and THD specs sound similar? I'am assuming that the pre-amp would be the one to dictate the overall tonality of the system.
Since my budget for this project is very small I was hoping to get a cheaper japanese power amp rather than a US or European brand, but with similar specs, without sacrificing much on overall sound quality. Would this be attainable? ???
Hoping for your inputs on this matter is highly appreciated. :) Tnx
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Between well constructed and designed power amps, you have to strain yourself to discern much sonic differences. I really doubt if listening at comfortable levels, you can distinguish between an Aragon, a Theta Dreadnaught or a Bryston. Well designed power amps are often flat from 1hz to 100khz at no more than 0.1db variation. With such flatness, the amp is really transparent and neutral so it shouldn't be coloring the sound so that it would have a sonic character distinct from that of another amp. Of course there are other traits like noise floor, slew rates, damping factors, harmonic and non-harmonic distortions. But in well-designed amps, these other specs are about the same across many and are so controlled as to affect the neutrality and transparency of the sonics at comfortable listening levels. You really would have to have a lousy power amp with a lot of coloration to make it sound different from another at those levels.
But, I have to say that many well-made power amps, or all amps for that matter, start to exhibit some coloration when driven to maximum power or above. That's because the sonic coloration starts to happen at the point approaching clipping distortions. Different amps have different clipping responses. That's where the true character of the amp starts to manifest itself. So if you want to distinguish sonic differences between well-made amps, you'd have to drive them close to or at rated power or beyond. I assure you it won't be a pleasant experience with the sales floor people to do that. ;D
Having said that, you could be able to distinguish Class A amps and Class A/B amps at very low listening levels. If the biasing on the Class A/B amps isn't well-thought out, it would sound harsh compared to a pure class A amp. That's because of crossover distortions. Class A amps have none of that. Class A/B amps, if not biased well, tend to exhibit some harshness at low volumes. But not to worry, many excellent well designed class A/B amps are biased to behave like class A amps at low volumes. So distinguishing between them might still be straining.
With regards preamps, most excellent preamps are also too neutral and transparent to make sonic difference. To my mind, there's only one type of preamp that makes sonic difference. This is the tube preamp. I won't go into discussion but suffice it to say that tubes color the sound as they produce even-ordered harmonic distortions than can put more body and presence to vocals and midrange instruments. SS power amps would amplify both the fundamentals and the even-ordered harmonics so that it sounds different form other SS preamps + SS power amp combinations.
Be a bit more careful comparing the specs of Japanese brands with European and American brands. They conform to different standards of measure so that an apple-to-apple comparison can be difficult if you can't read between the lines, especially with many Japanese CE brands.
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And why should they sound different?
The amplifiers' job is to boost line level signals(high impedance, low-level) to speaker level signals(higher voltages into low impedance speakers). Straight wire with gain has been the goal of amplifier design since day 1. Amplifiers are tasked to reproduce input signals faithfully without adding or subtracting, nor altering the envelope, pitch and phase of the input signal, they simply need to output signals that are exact replica of the input.
Unfortunately, these ideals are far from reality, never really realised....amplifiers have the job of controlling speakers and their cone movements.
Colorations occur, for example in tube power amps, you have capacitors in the signal path, and a transformer in the ouput to match output tubes to speakers. Then the tube themselves generate higher levels of second harmonics and thirds and fifths, this is more pronounced on SET amps than on push-pull amps. Is this good? that depends, as SET owners swear to find audio nirvana with them.
Capacitors alter phase and frequency response at a rate of 6db per octave, having several in the signal path has a cumulative effect. Transformers likewise present another coloration of its own, it limits your low frequency response due to core saturation, and has this "funny bussines" (resonance) above the audio frequency range owing to leakage inductance and interwinding capacitance.
While solid state amps can be designed to have none of the above traits, they too have their own shortcomings. In the race for lowest THD specs, ss amps were designed with very high open-loop gain, so that when negative feedback is applied the result is low THD. But then having low THD does not immidiately equate to good sounding amps as listening tests revealed. Thus TIM(transient intermodulation) and more recently PIM (phase induced modulation) were identified as the culprits. These issues were addressed by amplifier design having lower open loop gains and frequency response of 20hz to 20khz even before global negative feedback is applied.
So to answer your question, a tube pre-amp and an ss-amp combo is the way to go....a look at the surplus amps thread gives you a good clue. ;D
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Sa akin lang, I found B&K amps to be " Dark sounding". At first I didnt know how to describe it till a fellow member commented on B&K.
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Colorations occur, for example in tube power amps, you have capacitors in the signal path, and a transformer in the ouput to match output tubes to speakers. Then the tube themselves generate higher levels of second harmonics and thirds and fifths, this is more pronounced on SET amps than on push-pull amps. Is this good? that depends, as SET owners swear to find audio nirvana with them.
Capacitors alter phase and frequency response at a rate of 6db per octave, having several in the signal path has a cumulative effect. Transformers likewise present another coloration of its own, it limits your low frequency response due to core saturation, and has this "funny bussines" (resonance) above the audio frequency range owing to leakage inductance and interwinding capacitance.
... indeed "funny" how those tube amps were made to make sounds, though they are indeed amps' marvel way back ... and even amusing how audiophiles loved their sounds ... which makes coloration part of the norm in designing new ampifiers today - personal preferences can dictate how an amp should sound! Thus, differences are being forced right into the amp by the pre-amp stages.
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While solid state amps can be designed to have none of the above traits, they too have their own shortcomings. In the race for lowest THD specs, ss amps were designed with very high open-loop gain, so that when negative feedback is applied the result is low THD. But then having low THD does not immidiately equate to good sounding amps as listening tests revealed. Thus TIM(transient intermodulation) and more recently PIM (phase induced modulation) were identified as the culprits. These issues were addressed by amplifier design having lower open loop gains and frequency response of 20hz to 20khz even before global negative feedback is applied.
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I translate this like those specs can not represent how good or bad an amp is! I have tested different combination of amps and speakers and encountered bad sounds ... but in the same manner, came across with good combinations ... somehow leaning on one of the conclusion of one tech guy who verbalized my impression that 'sonic quality is inversely proportional to watts quantity', and I tend to agree with him on this finding. Thus, the popular phrase 'the precious 1 watt'! ;D ;D
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So to answer your question, a tube pre-amp and an ss-amp combo is the way to go....a look at the surplus amps thread gives you a good clue. ;D
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I like your recommendation ... the tube will always present a dynamic pre-amp having high bias voltage and class A amplification with tolerable (lovable) coloration. However, would mating it with SS amp end you up with the SS limitation? (though to me, I would rather embrace SS limitation than accept tube limitation)
Further, I can not ignore those who tested the stock T-amp - majority of them in the full range high sensitivity drivers - that this amp proposes an alternative to both the pre-amp and amp. Of course, this introduces yet another problem of its own, not in the electronics area but in the choice of the speakers. This is the option I bet nowadays to shy from the inherent problem of tube and SS (conventional) amplification.
If I can get more indulgences from you ;D ;D ;D ... any recommendation for a tube pre-amp? Will try it for once with my NEC-A10II SS amp (as separate) if it will offer competion with an all NEC-A10II setup, or regulated GC, or SNMPed T-amp, Yamaha Class A, or the Technics hybrid SVI chip, all driving a high sensitivity full ranger.
Er, what's 'dark sounding' means?
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I can not ignore those who tested the stock T-amp
"they simply need to output signals that are exact replica of the input" this could be it... ;D
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... indeed "funny" how those tube amps were made to make sounds, though they are indeed amps' marvel way back ... and even amusing how audiophiles loved their sounds ... which makes coloration part of the norm in designing new ampifiers today - personal preferences can dictate how an amp should sound! Thus, differences are being forced right into the amp by the pre-amp stages.
I translate this like those specs can not represent how good or bad an amp is! I have tested different combination of amps and speakers and encountered bad sounds ... but in the same manner, came across with good combinations ... somehow leaning on one of the conclusion of one tech guy who verbalized my impression that 'sonic quality is inversely proportional to watts quantity', and I tend to agree with him on this finding. Thus, the popular phrase 'the precious 1 watt'! ;D ;D
I like your recommendation ... the tube will always present a dynamic pre-amp having high bias voltage and class A amplification with tolerable (lovable) coloration. However, would mating it with SS amp end you up with the SS limitation? (though to me, I would rather embrace SS limitation than accept tube limitation)
Further, I can not ignore those who tested the stock T-amp - majority of them in the full range high sensitivity drivers - that this amp proposes an alternative to both the pre-amp and amp. Of course, this introduces yet another problem of its own, not in the electronics area but in the choice of the speakers. This is the option I bet nowadays to shy from the inherent problem of tube and SS (conventional) amplification.
If I can get more indulgences from you ;D ;D ;D ... any recommendation for a tube pre-amp? Will try it for once with my NEC-A10II SS amp (as separate) if it will offer competion with an all NEC-A10II setup, or regulated GC, or SNMPed T-amp, Yamaha Class A, or the Technics hybrid SVI chip, all driving a high sensitivity full ranger.
Er, what's 'dark sounding' means?
I love hybrid too. I agree with embracing the limitation of SS rether than the limitations of tube.
Dark sounding means very warm but with a "dark" background (opposite of T-amp's "clean" sound), somthing like that.
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"they simply need to output signals that are exact replica of the input" this could be it... ;D
... and end up with mucho praise from the big leagues!!! :o :o :o
what makes them so different from other amplifiers that are supposedly designed to do the same thing to warrant attention from those "cultic" (tube head) audio hobbyist?
Dark sounding means very warm but with a "dark" background, somthing like that.
... am still at a loss ;D ;D ... 'dark' as in dark (patay ilaw?) ... or dark as in dead silence? ... or is it a music playing but with a dead silence in the background - or how could there be dead silence in the background if music is playing? ... I somehow experience this type of listening when I first listen to NEC-A10II at home, I mean a dead silence in the background every after music track which I do not normally notice in my other amps - do not understand how to describe it really! ???
thanks for the reply :)
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I translate this like those specs can not represent how good or bad an amp is!
i can write volumes about this... ;D specs alone does not give the complete picture, things like clipping behaviour or how the amp recovers from an overload are the more important aspects, i believe.
any recommendation for a tube pre-amp?
firstly with today's recordings that are quite loud, with levels of 2volts or thereabouts, a pre-amp may not even be required,with that level and an amp with a gain of 20 into an 8 ohm speaker, this would translate to 200 watts, so a simple passive level controller maybe all that is required. so why use tube pre-amp? to get that coloration which are euphonic... ;D a dose of 2nd order harmonics from a common cathode tube pre-amp may do your ears some good. ;D
here is a good read:http://www.diyaudio.com/forums/attachment.php?postid=1146140&stamp=1172638879&s=195ddc7bdcd8b15160eb706cb06ad3df (http://www.diyaudio.com/forums/attachment.php?postid=1146140&stamp=1172638879&s=195ddc7bdcd8b15160eb706cb06ad3df)
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i can write volumes about this... ;D specs alone does not give the complete picture, things like clipping behaviour or how the amp recovers from an overload are the more important aspects, i believe.
firstly with today's recordings that are quite loud, with levels of 2volts or thereabouts, a pre-amp may not even be required,with that level and an amp with a gain of 20 into an 8 ohm speaker, this would translate to 200 watts, so a simple passive level controller maybe all that is required. so why use tube pre-amp? to get that coloration which are euphonic... ;D a dose of 2nd order harmonics from a common cathode tube pre-amp may do your ears some good. ;D
here is a good read:http://www.diyaudio.com/forums/attachment.php?postid=1146140&stamp=1172638879&s=195ddc7bdcd8b15160eb706cb06ad3df (http://www.diyaudio.com/forums/attachment.php?postid=1146140&stamp=1172638879&s=195ddc7bdcd8b15160eb706cb06ad3df)
I thought nobody paid attention!
I also noted that standard CD output that can go 2V pk-pk - too high for those vintage, and sometime causes those gems to somehow induce interruptions to music.
You are right in saying I should get rid of the preamp if I will be using CD/DVD player. So as not to overload my player by the low input impedance of the MAIN-IN (typically 10k), I should come up with passive controller.
I want to experiment using tube ... for what reasons? - wala lang, to hear what's in there! ;D ;D tingnan ko kung ma loves ko rin yung euphonics that they are so fond of.
thanks for the link ... i knew I read this before, but good to review it again.
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last wednesday, Gerry(tube magnate) and myself paid a visit to Mang Rod, you should try one of his tube preamps or maybe request him to make you a tube buffer..... ;D
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last wednesday, Gerry(tube magnate) and myself paid a visit to Mang Rod, you should try one of his tube preamps or maybe request him to make you a tube buffer..... ;D
I just borrowed one of his creations from another member. All I can say is equipment matching is important.
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last wednesday, Gerry(tube magnate) and myself paid a visit to Mang Rod, you should try one of his tube preamps or maybe request him to make you a tube buffer..... ;D
Who's Mang Rod? apology for my ignorance! ;D
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do power amps sound the same? it depends on what you mean by "power amps" and "the same".
if you are generalizing all power amps ever made, then no, not all the millions of amps in the world all sound exactly the same.
but there will be amps that sound similar (if that's what "the same" means in this context).
so the answer to the generalization is also a generalization: Yes if they sound the same, and No if they don't sound the same.
but i think what you are asking is "do the cheaper japanese power amps sound good enough that i don't have to spend on a higher priced US or European power amp?"...... only you can answer this because the key phrase here is the very subjective "is it good enough?"...... nobody here can decide for you what is good enough.
so the usual advice here is audition audition audition.
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Who's Mang Rod? apology for my ignorance! ;D
Here is Mang Rod's Blog Site
http://trodt-audio.blogspot.com/ (http://trodt-audio.blogspot.com/)
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Here is Mang Rod's Blog Site
http://trodt-audio.blogspot.com/ (http://trodt-audio.blogspot.com/)
thanks kefq!
to further matzter ... ;D
music listening is an art ... art appreciation is different for each people ... so even the sound that you want to hear is largely dependent upon you ... it may even be dictated by the art of what you wanted to see in your gear, not just the sound that emanates from it ... thus, the choice of speaker, the player (good ol' vynil, tape, CD, SACD, DVD-A, and now MP3, and MP4), your home setup, the sub, etc became an integral part of that art of listening (and sights) ... to this end, the 'amps' (probably the integrated) or typical AVR may sound differently (considering those DSP flavors available in many "amps" now ... tailor it for what you want!
But to go back to the original term if power amp, technically, amp is just amp - to amplify a signal, make big a small but same replica ... to this end, amp (as in power amp) should sound the same, for straight pre-amp meant to amplify (and not to color the output), the integrated should also be sounding the same ... This has been demonstrated already in the past, where both tubes and SS were adjusted on the same level, and hardly anybody can distinguish differences, and the most part of the fun was that a cheapy simple SS stereo came out as the "choice" to the astonishment of one "high" end (translated: pricey) manufacturer who also took part of the event - the designer knew it and did not offer an explanation, technical as he is, that should be expected.
The limitation of every part comprising the amp, the forceful introduction of pre-amp coloration, the varying degree by which we listen and operate our amps (volume level), the speakers that articulate the amps output, the quality of music materials played ... now resulted to differences in sound in amplifiers ... but dont account the differences to the amplifiers ... it is most often 99% attributable to something else ... because again, if that amplifier were to be adjusted in same level, and all non-amp artifacts forcefully introduced to it is netralized using the controls of that same amplifier, those amp will just be an amp designed to copy the original signal and just make it big ... and YES, they should sound the same.
But NO, "amplifiers" (notice the qualifying quotation marks ;D) will not sound the same ... more often than not largely due to the stages surrounding the amplifier (but not the amplifier itself), inclusion of the (art) designers' own artifacts for reason of euphonics, or demands of certain segment of the (artistic) listeners for a certain sound, or sheer commercial quantity (art of business) where the issue of sound reproduction is not so much an issue for almost 80-98% of the consumers!
As some people say ... your art is your art ... to each his own then!
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and the misunderstanding starts from confusing art with science and vice-versa..... :'(
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and the misunderstanding starts from confusing art with science and vice-versa..... :'(
Yeah!!!
... that's why there are many followers of the wrong reasons ... just because it was heard some way, it must be it ...
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hhmmm... power amps... listen...
to the music, not to the wise@ss that keeps on bothering you with things you wouldn't understand while you are trying to listen.
coz if it were that simple, then everybody would have had the same amp. and if it all were the same, then everyone would have been able to built it exactly the same. sometimes people forget that that is what you pay for.
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hhmmm... power amps... listen...
to the music, not to the wise@ss that keeps on bothering you with things you wouldn't understand while you are trying to listen.
coz if it were that simple, then everybody would have had the same amp. and if it all were the same, then everyone would have been able to built it exactly the same. sometimes people forget that that is what you pay for.
Yes, in fact, it is not really that simple because the question is not really simple (it is technical) ... and simply because preferences and marketing hype play big roles in the building of "amps" (now also being associated with integrated amps or receivers)
If you meant integrated amps or receivers, that's easy - by all means they sounds differently ... but again, to say its the POWER AMP that sounds different IS THE WRONG REASON ...
if it were just POWER AMPS, and complied to the same yard stick (say at about 1% THD amplification), they will sound the same in a controlled listening provided they operate at the same level where all amps will be within operating conditions (SOA) ...
... but the real world of listening (the art of listening) varies, since some of us wanted it loud, some want it soft, some wanted exageration on certain bandwidth (e.g. bass or mid or air of HF) forces differences of amp behavior (not really the sound) - so you have clipping, distortions, etc - this is not the amp sound - this is the effect any amp will have driven beyond its SOA
... but the real world employs (the art of choosing) different speakers (sama mo na cable, players) ... different players have different output level (the standard given is in the range, not fixed), ... speakers vary in sensitivity, some were forced to exagerate certain frequencies, some sets have unusually high impedance swings ... some high end cables are typically capacitive ... but will all this change the SOUND of an amplifier in a controlled environment? Of course amplifier will react differently to this situation, driving your amp again beyond its possible SOA ... and even high end (that you pay for) are not immune to this amplifier behavior! ... and some cheapies are sometimes more tolerant in this regard ... as usual, it is not really what you pay for that counts ... finding the right synergy?
... but the real world employs (the art of making) business ... hyping is standard, both in the mass market and the high end, more so with the cheapies ... and there are instances that cheapies became high ends, not by virtue of its inherent characteristics, but by virtue of some people who discovered it, and bought it en masse, and put a high tag on it ... or like the T-amp hyped no end by tubies themselves ... then we have the mushrooms for small business ... does this change the sound of the T-amp if it were subjected to listening test in a controlled room? Or does T-amp speaks of its quality side by side with mass market products, mid-end or even high end products just by looking on its PRICE TAG?
Amplifier is a simple device ... the most tamed in your audio chain ... having from negligible to about 1%THD for decent gear ... in fact almost perfect ... it is just made complex, not by the AMP itself, but by the THINGS you feed the amp ... thus in SEPARATE world, you build your sound to your liking, the AMP will not be it - for it will just be the device to multiply its replica ... so you get your pre-amp that has its sound signature, you get player that has its sound signature, you get speaker that has sound signature, you end up in a house that has its own signature, and you buy pCDs that has its own signature as well at kung mamalasin ka pa, your ears may have the worst signature ... do all these signatures change the sound of the AMP, of course! ... is it because of the AMP? of course not!
Lastly ... nobody in his right mind in the business world will want amplifier done (or will claim done) in the same way ... they may not be hyped anymore ... bad to business! ... so, to make a unique braggings, manufacturer will surely hype a phrase, inject their own signatures into the amp ... and the good ol' amp just amplify what you feed it perfectly as you want it - IS IT THE AMP that changes its tonality?
Do power amps SOUNDS the same?
now, IS THE $OUND OF A HIGH END AMP DIFFERENT FROM THE SOUND OF A cheap AMP (baka lumabo pa, those that have less than 1% THD)? ... because you have complex world, you end up buying amp with its pre-amp na ... what can we do? ... but dont blame the amp for its sound, blame those DSP's and pre-amp if you may, they were there by force! ;D ;D ;D
Just my thought 8)
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it was demonstrated before in a blind test that the lowly pioneer amp was indistinguishable from the high-end futterman tube amp.... ;D
they sounded the same.... ;D after all the hypes, this has to come to this....
so, each one to his own choice....no shame in this.....nothing could be fairer than this.... ;D
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it was demonstrated before in a blind test that the lowly pioneer amp was indistinguishable from the high-end futterman tube amp.... ;D
they sounded the same.... ;D after all the hypes, this has to come to this....
WOWOWOWIE!!! :o :o :o
I salute you!!! what a memory! I have it in the corners of my small brain ... but seemed cant find it in the heap of my files ...
Indeed, it was a good reality check to those who ride high on the many hypes of this hobby ...
... hypes are good for the businessmen (translation: the blurrier a product is, the better hypes they can invent and potentially better sales from quick believers)
... knowledge are good for the consumers (translation: if you dont know what you are buying, chances are, you will not end up with what you want, or if you end up with what you want, you were ripped off! ;D)
...so, each one to his own choice....no shame in this.....nothing could be fairer than this.... ;D
Indeed!!! This is how the art of listening (and probably system building), in the first place, should be enjoyed! :) :) 8)
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or if you end up with what you want, you were ripped off! )
happens more often than not... ;D
here is a good read:http://www.diyaudio.com/forums/showthread.php?s=&threadid=3812&highlight= (http://www.diyaudio.com/forums/showthread.php?s=&threadid=3812&highlight=);http://www.diyaudio.com/forums/showthread.php?s=&threadid=12752&highlight= (http://www.diyaudio.com/forums/showthread.php?s=&threadid=12752&highlight=)
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happens more often than not... ;D
here is a good read:http://www.diyaudio.com/forums/showthread.php?s=&threadid=3812&highlight= (http://www.diyaudio.com/forums/showthread.php?s=&threadid=3812&highlight=);http://www.diyaudio.com/forums/showthread.php?s=&threadid=12752&highlight= (http://www.diyaudio.com/forums/showthread.php?s=&threadid=12752&highlight=)
Good read at the start ... but painfully waste of time in majority ... anyway, I can only recognize different cultic groups trying to include those items that force coloration into the sounds of a power amplifier (DSPs, pre amps, cable, speakers, players) which make the topic too muddled to be a productive reading in totality ... and yes, different technical background, unestablished terms (semantics) can turn such discussion into a sort of spaghetti ...
It is rather interesting that Bob carver did duplicate a 'high end high tag' dual mono ek-ek amp using cheap parts ... and when listening tests, metrics are all out, all gold ears were red faced not to identify which is which! I admit though that faith is really hard to knock off out of a person ... it defies science, statistics, reality, metrics, AB experience ... but it does not alter the fact.
Reality may take so many high end stakers out of employment and profit ... a lesson learned by stereophile and other high end price taggers ... to shy away from any same-sound technical test ... or be included into the books of vintage companies!
;D ;D ;D
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Some thoughts of an old European. I am biased, I like vintage Onkyo amplifiers, the one I use is over 30 years old.
As many have allready stated: amplifiers should amplifie not sound like anything.
Tubes are over and out. Due to their physical caractaristics high end tube amplies always lose from high end solid state amplies.
There is no real need to buy separate pre- amp and power amp, integrated is oke as long as the pre amp and power amp have their own separate power suply. So if the voltage of the power amp goes down at verry high volume, the voltage of the pre amp stays stable.
If you compare power output from amplies RMS (root mean square) and DIN (Deutsche Industrie Norm = German industrial standard) are objective ways to messure power output.
In theory class A amplies are better than class B, they avoid the problems that might occure when the amplie switches from one power transistor to the other. However the power transistors are always running at rated output so they always get hot and skyrock your electric bill. There are perfect class B amplies.
Never use your amplie at maximun power output, you get harmonic distortion like hell and when the thing starts clipping it might ruin your speakers, specially your tweeters.
If you want a lot of noise dont only look at the power of your amplie. Remenber the Db scale is logaritmical so 200 watts do not get you 2 times the noise of 100 Watts. Also look at howmany Db the speaker produces at 1 watt input, measured at 1 meter from the speaker. Bass reflex speakers tend to produce more sound than closed cabinet speakers.
The most important element in your audio chain are the speakers. Speakers always color the sound. There are no speakers with a flat frequencie response and even if there were there is the accoustics of your listening room. I would recomment to spend at least half your budget on speakers. And try to listen at them at home, in a noisy sales room you can not compare.
Actually the amplifier is the easiest part of your audio chain, the quality of your source and speakers are more important for the sound quality you will get.
Leo.
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@ditterdi,
welcome to pinoydvd, wise words indeed..... ;D it is funny how many fall for the hypes and myths without really understanding all issues...
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There is no real need to buy separate pre- amp and power amp, integrated is oke as long as the pre amp and power amp have their own separate power suply. So if the voltage of the power amp goes down at verry high volume, the voltage of the pre amp stays stable.
Unfortunately, how many commercial integrateds are there with separate PSU for their preamps and power amps? Maybe I'm just out of touch with current integrateds. Are there? ;D
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Unfortunately, how many commercial integrateds are there with separate PSU for their preamps and power amps? Maybe I'm just out of touch with current integrateds. Are there? ;D
I think they are ... if you mean separate transformer sight, it is not like that ... but in typical commercial integrated and receiver, the PSU coil of pre-amp usually is separate from that of the power amp ... in this manner, the sag in the power amp due to voltage drop in the coil from high current demand is not reflected at the pre-amp coils ... though what I know is that it is better to have the pre-amp coil in a separate bobbin! ... when I dissected my Pioneer SA8800, the pre-amp PSU is regulated while the power-amp PSU is the one with fuse protection.
Some thoughts of an old European. I am biased, I like vintage Onkyo amplifiers, the one I use is over 30 years old.
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The most important element in your audio chain are the speakers. Speakers always color the sound. There are no speakers with a flat frequencie response and even if there were there is the accoustics of your listening room. I would recomment to spend at least half your budget on speakers. And try to listen at them at home, in a noisy sales room you can not compare.
Actually the amplifier is the easiest part of your audio chain, the quality of your source and speakers are more important for the sound quality you will get.
Leo.
Welcome Leo!!! :) Where havy you been? ;D ;D
A credible advise to those serious in finding which sounds kick at the right price! 8)
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when I dissected my Pioneer SA8800, the pre-amp PSU is regulated while the power-amp PSU is the one with fuse protection.
this is common in many japanese integrateds, and for the reason you stated...it makes a lot of sense to design in that way...
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Hi,
I am from the Netherlands (Holland), married to a Filipina. my wife has been living in the Netherlands with me for 12 years. We decided to swap country so now we are living in Dinalupihan Bataan.
Leo.
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This is regarding damping factor. How true?
High damping factor -> SS sound
Low damping factor -> tubey sound
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This is regarding damping factor. How true?
High damping factor -> SS sound
Low damping factor -> tubey sound
the reason why SS amps have high damping factor is that is uses global negative feedback, whereas tube amps does not nescessarily use it...tube amps can be designed to have high damping factor...
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This is regarding damping factor. How true?
High damping factor -> SS sound
Low damping factor -> tubey sound
Quite true. Some tube amps can go as high as 100, but rarely beyond that, most hover in the 20 range. And this often explains why tubes are on the mellow side and SS power amps more biting. Typically at around 1000, well designed SS amps are generally more accurate in controlling driver movements primarily because of a higher damping factor. The Nu Froce Reference 8.5 has a damping factor of 4000. Now that's like having a vise grip on woofer movements. The amp literally tells the woofer where to go and when to stop with supreme precision.
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Interesting. So if you want a tube hybrid setup, go for a low damping factor SS amp for a more "tubey" sound? instead of a high DF?
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no, what that post simply means is that an amp with a very high damping factor controls speaker movements better. the speaker cone assembly having a definite mass will have inertia, so that after the electriucal signal has subsided, the movemement still goes on due to inertia, so this adds another coloration of its own.
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Wowowie! Thanks to everyone for injecting there thoughts on the topic. :o It's a highly educational trip reading this thread!! I thought I was in a Audiogon forum! ;D Seeing the remarks here it seems that it's probably a universal consencus, that the bottom line is "the beauty (of sound) is in the ears of the beholder".
I gathered that, technical or physical aspects in making an amp may differ, to a certain degree, but a lot of other attributes has to be considered. This includes associated equipments, listening room, choice of music, etc. I must say that another influence here is the stigma of "brand mentality". I say this because , in numerous occasions, I noticed a lot of audiophiles tend to "pre-judge" an equipment because of its brand.
Now, here is a follow-up question and more specific. Would a Sony T-AN55ES power amp, rated at 120watts/ch. rms be more or less similar to lets say a bryston or aragon power amp with similar watts, assuming all other associated equipments are constant and the system will not be driven to clipping (normal level only). When I say similar, will the final sound of the system be almost the same or radically different. Personnally,I'am assuming that the power amp would hardly be a factor in the overall sound.
Thanks again guys for a splendid support! ;)
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no, what that post simply means is that an amp with a very high damping factor controls speaker movements better. the speaker cone assembly having a definite mass will have inertia, so that after the electriucal signal has subsided, the movemement still goes on due to inertia, so this adds another coloration of its own.
Sir Tony,
In sonic terms (since I can not see which is extra inertia and which one is the sound itself ;D ;D ;D), how would you know that what you are listening to are an effect of bad damping effect? ::) ::)
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...
Now, here is a follow-up question and more specific. Would a Sony T-AN55ES power amp, rated at 120watts/ch. rms be more or less similar to lets say a bryston or aragon power amp with similar watts, assuming all other associated equipments are constant and the system will not be driven to clipping (normal level only). ...
The test you are proposing is easier (SS to SS) compared to what has been done in the past, that of cheap SS and a high cost monoblock tube. If all of them are purely power amp, and any of the pre-amp to be used with them are adjusted such that the end signal (after amp) are of same loudness level - it is most likely, like other test in the past, will just sound the same, that is, highly indiscernible even with those claiming 'golden ears'.
...
I say this because , in numerous occasions, I noticed a lot of audiophiles tend to "pre-judge" an equipment because of its brand.
...
Maybe am an audiophile before because I prejudge equipment based before on its brand! ;D ;D ;D
In truth, not only branding are used to pre-judge an equipment. Sometimes, one or combination of the following are used to pre-judge a system:
(1) price (if expensive, it must be audiophile)
(2) materials used (if it used exotic components and cables, then it is audiophile)
(3) construction (e.g. if it uses heavy torroid, and holco resistor, etc etc, it is audiophile)
(4) looks (it posseses hypnotic looks, pleases my eye, I want it as my audiophile ;D)
(5) my friend said it is audiophile, it must be audiophile
(6) 80% of the store said it is audiophile, then it is audiophile
(7) 60% of my community (pinoydvd? ;D) said it is audiophile, it must be audiophile
(8) weight (it weighs 80kg, it must be audiophile ;D ;D ;D ;D ;D)
(9) I heard it audiophile, it should be audiophile :D :D :D :D
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aHobbit, You scored 9/9=100% !! ;D I guess the true criteria ,the sound!!!, can't really be made concrete. Nobody can really define the boundary between mid-fi and hi-fi when it comes to the sound. Its really a personnal opinion. Tnx
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Sir Tony,
In sonic terms (since I can not see which is extra inertia and which one is the sound itself ;D ;D ;D), how would you know that what you are listening to are an effect of bad damping effect? ::) ::)
it is hard to describe really, but there was this "motional feedback amp-speaker system" demonstrated by Philipps IIRC, wherein there was this band playing "live" in a corner inside of a cafe, when one by one, the band members took off until all them were gone, and yet the music still played on. to the delight of the audience, they were hoodwinked into believing that they were listening to a live performance when all the while it was just recorded music..... ;D ;D ;D
to put it simply, the speaker movements were sensed as to direction and any error was immidiately corrected...
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...
Nobody can really define the boundary between mid-fi and hi-fi when it comes to the sound. Its really a personnal opinion. Tnx
...
Are you starting a debate? ;D ;D ;D
What you stated above is basically the same argument I raised in one of the thread in this forum - that is to define mid-fi from hi-fi. And all I got is just noise, and no clean signal whatsoever. It seemed to me that majority of stereo listeners who claimed they have audiophilia blood can not categorically define the limit of when a mid-fi is mid-fi and when a hi-fi is hi-fi. The thread has RIP in it, so dont bother! ;D ;D ;D
Er, how do you like your coffee sir?
(a) mid coffee (b) low coffee (c) high coffee (d) coffee less (e) coffee more
The cream sir?
(a) mid (b) low (c) high (d) less (e) more
The cup sir?
(a) plastic (b) aluminum (c) steel (d) wood (e) bronze (f) silver (g) gold
How about the coaster? the teaspoon? the sugar? the table? the temperature?
A bit further sir ..... do you have a tongue?
Just a warning sir ... you will have fatigue drinking mixture with less (real) coffee!!!
Because your brain will fill in the gaps of those taste missing in the coffee ... and your brain will eventually get tired doing that for you.
;D ;D ;D Sorry, was just carried away!!! ;D ;D ;D
taste it! enjoy it!
I think my coffee is more (closer to the real) coffee than yours!!! ;D ;D ;D
Or probably, the pasture is always greener at the other side!!! :D :D :D
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...
the band members took off until all them were gone, and yet the music still played on. to the delight of the audience, they were hoodwinked into believing that they were listening to a live performance when all the while it was just recorded music..... ;D ;D ;D
kakatakot pala effect ng mababang damping factor!!! ;D ;D ;D
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to put it simply, the speaker movements were sensed as to direction and any error was immidiately corrected
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I may not see it myself ... but maybe somehow, if I have a good speaker, and somehow it sounds lifeless or dull ... chances are, the extra motion of the speaker affects the sonic quality of the outputted sound due to a low damping factor ... I bet, you need higher damping factor to system that permits more bass into the output ... I just thought that since mid and HF do not really require so much power as bass, the need for higher damping factor for a system that drives mid-hi is not as much as the one that will have the sound outputted as full range (which include the lower bass region of 20-100Hz) ... or am I talking sense here? ??? ???
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Damping factors have the most effect at low frequencies than at mids and highs. That's why some amps specify the DF into a load at a certain frequency, often at 60hz.
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to put it simply, the speaker movements were sensed as to direction and any error was immidiately corrected...
I have one (snif snif only 1). They are small and have 2 build in amplies one for the midrange and tweeter and one for the bass. The bass speaker has a build in piezo christal that reports the movement of the speaker to the system, so errors can bee corrected.
They have no pre-amplier but can be connected to the speaker out of another amplie or to a pre-amplie.
They sound fantastic. There are still a lot floating around and they are worth good money.
Leo.
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Damping factors have the most effect at low frequencies than at mids and highs. That's why some amps specify the DF into a load at a certain frequency, often at 60hz.
Yup, this is what I am saying that in the bass region, high damping factor is more required than in mid-hi.
If you have low damping factor, and your system is into lots of low end (bass region), then the life of your mid-hi can be sucked out by the unwanted return movement resulting to dull or lifeless sound.
Of course, it can also result in a confused bass sound!
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Damping factors have the most effect at low frequencies than at mids and highs. That's why some amps specify the DF into a load at a certain frequency, often at 60hz.
yes, while SS amps can have high DF at any frequency within its passband, DF in the high frequencies are diminished because of the boucherot cells and or zobels connected at their outputs, these are needed in order to isolate the amp from capacitive loads...
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yes, while SS amps can have high DF at any frequency within its passband, DF in the high frequencies are diminished because of the boucherot cells and or zobels connected at their outputs, these are needed in order to isolate the amp from capacitive loads...
But I understood those zobels are way beyond the audio band and its purpose is to avoid ringing (high frequency loop), so the DF should still be effective within the audio spectrum ... or is ringing a form of unwanted cone movement on the HF level?
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But I understood those zobels are way beyond the audio band and its purpose is to avoid ringing (high frequency loop), so the DF should still be effective within the audio spectrum ... or is ringing a form of unwanted cone movement on the HF level?
yes, but you'll be surprised how the output impedance of the amps increases with those once you do the math...any way speakers become both inductive and capacitive within the audio band...
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Will a power amp that doubles its power rating at 4 ohms sound better or of better quality than an amp doesnt double at 4 ohms?
TIA :)
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SQ aside, I (just me ha?) believe that spec means little. You can always rate the amp lower for 8 Ohms to make it appear half of the rating for 4 Ohms.
Anyway, between
Amp A w/ 50W into 8 and 100W into 4
and
Amp B w/ 75W into 8 and 100W into 4,
I'd choose Amp B because I will get more power in 8 Ohms (SQ aside because the ears will decide hehehe)
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SQ aside, I (just me ha?) believe that spec means little. You can always rate the amp lower for 8 Ohms to make it appear half of the rating for 4 Ohms.
Anyway, between
Amp A w/ 50W into 8 and 100W into 4
and
Amp B w/ 75W into 8 and 100W into 4,
I'd choose Amp B because I will get more power in 8 Ohms (SQ aside because the ears will decide hehehe)
I would choose the A amp because it probably has a better power suply.
Leo
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I would choose the A amp because it probably has a better power suply.
Leo
You can always overkill the power supply for both Amps A and B and they'd still be rated the same way. Output power for a certain load will be limited by the current capability of the amp.
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SQ aside, I (just me ha?) believe that spec means little. You can always rate the amp lower for 8 Ohms to make it appear half of the rating for 4 Ohms.
Anyway, between
Amp A w/ 50W into 8 and 100W into 4
and
Amp B w/ 75W into 8 and 100W into 4,
I'd choose Amp B because I will get more power in 8 Ohms (SQ aside because the ears will decide hehehe)
By the specs, they are just the same into 4 ohms.
Amp B could have a higher bias into 8 ohms that's why it can attain 75watts [Power in watts = Vsquared/R, where R, the impedance of speaker, held constant will yield higher V than with the lower 50W of Power in 8 ohms].
Amp A could have been biased lower into 8 ohms so it can only attain less than 75watts.
Both Amps can deliver the current demands (because both can supply the current to attain 100watts at 4 ohms) .
In 8 ohms, the limiting factor of the power for both amps is not the ampacity of the power supply but the bias voltage!
In 4 ohms, they are just the same in RMS.
However, I will not be surprised if the headroom of amp B (being biased higher) will be better than amp A. (bigger headroom, technically, is more dynamics).
In 4 ohms, the limiting factor of the power for both amps is the ampacity of the power supply!
With the above choices, I will go for Amp B.
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A power amplifier that doubles its power when the load is halved is said to behave more linearly across the audio spectra than one that doesn't. So I'd choose amp A with all else equal. It even has a higher headroom at 3db. But if you want more power into 8ohms, then amp B is better, just don't use material that will require 3db peaks at the rated power.
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Power in watts = Vsquared/R, where R, the impedance of speaker, held constant will yield higher V than with the lower 50W of Power in 8 ohms].
I will go for Amp B.
Power=Watts (W)
Current=ampere (I)
Impendance-resistance=Ohm(R)
Power=Voltage*Current W=V*I
Voltage=Resistance*Current V=I*R
So Power=Current square*R W=I^2*R
Leo.
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A power amplifier that doubles its power when the load is halved is said to behave more linearly across the audio spectra than one that doesn't. So I'd choose amp A with all else equal. It even has a higher headroom at 3db. But if you want more power into 8ohms, then amp B is better, just don't use material that will require 3db peaks at the rated power.
avphile,
75watts is only a label ... had amp B used 50watts into 8 ohms (which it can, it may now alter your conclusion), the 2 amps has no difference (because both of them can now equally double its power, if 50watts is the reference point) ... and how did you compute 3db headroom (am refering to dynamic headroom) where in fact dynamic power was not given into 8 ohms?
at short burst, because of high bias in ampB, it can accomplish higher power both in 4/8 ohms ... that is granting, since it is not given, no 4/8 ohms switch is available ;D
I can show it mathematically if you will let me ;)
To further ditterdi,
I = V/R
from P = VI, then P = Vsquared/R
regards
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The math . . .
I did my LM3886 power amp and it is a good exercise of these simple formula ...
Let's design a 50-watt amp into 8 ohms. So I need to know the bias voltage.
P = Vsquared/R : P = 50 = Vsquared/8
Vsquare = 400 Vsquare : Thus, V = =/- 20Vdc
(I will not deal with factor of 1.4 for simplicity of presentation)
What bias do I need to come up with 100W into 4 ohms
100 = V^2/4 : this is simply V = +/- 20Vdc (as well)
Thus, a Vdc of +/-20 will yield me 50W/8ohms and 100W/4ohms.
From the equation P=VI, we can solve the current into 4/8 ohms respectively.
4ohms: I = 100W/20V = 5A 8ohms: I = 100W/20V = 2.5A
Checking it out:
I=5A to 4ohms load will deliver I^2*R = 100W power!
I=2.5A to 8ohms load will deliver I^2*R = 50W power!
I have to ensure I will not go over 100W/4ohms to protect the amp. Thus, I have to limit my fuse rating to 5A. I need a power supply able to deliver 5A with a tap voltage equivlent to +/-20Vdc.
Then, I will get all my parts now and contruct my amp. I have one designed at 60W/4ohms and 30W/8ohms (LM3886).
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To those who want to exercise ... I may be wrong here ... feel free to point it out ...
Lets design a 75W/8ohms
The bias voltage I need should be: P=V^2/R = 75W = V^2/8ohms : V^2 = 600Vsquare
This will give me about +/-24.5Vdc.
However, based on previous computation, I only need +/-20Vdc to accomplish 100W/4ohms.
Let's see the current:
I = P/V = 75W/24.5V = 3.06A to accomplish a 75W/8ohms
Again, to accomplish 100W/4ohms, I only need 5A.
The difference of this amp to the previous amp is only the bias voltage I have to implement! Here I need same power supply that can handle 5A but with tap voltage equivlent to +/-24.5V. The PSU of previous amp can only handle P=VI=20V*5A=100W max (simple computation for presentation only), while this amp transformer can handle P=VI=24.5V*5A=122.5W
And with this bias voltage, my amp can kick at 4 ohms about :
P = V^2/R = (24.5V)^2/4ohms = 600/4 = 150W (dynamic power burst) giving me 150w (dynamic power)/100w (rated power) of about less than 3db into 4 ohms.
(This is with the assumption that both amplifier were limited with those computed bias voltage, which in real life is more than that because of ac/dc conversion factors).
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If you run 24.5V into 4 Ohms, you get 6.125A. E, 5A lang fuse mo.
Btw, isn't it that supply voltage is held constant?
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If you run 24.5V into 4 Ohms, you get 6.125A. E, 5A lang fuse mo.
Btw, isn't it that supply voltage is constant?
omaygawd!!! :o :o :o ... But my fuse is slow blow ::) ;D ;D ;D
You are correct, if my fuse is fast blow, this will trigger the protection mode of the amplifier.
Also, as I said in my post, values are higher than what has been presented (for simplicity of computation). Short burst as in music reproduction do not blow fuse. The RMS (average) value of power usually will trigger protection mode.
Typically, manufacturers allow a 10% overload to have the amp deliver power at 10%THD. So to do this, I can have ampA fitted with 5.5A. If this amp go beyond 5A (burst mode) at 4ohms, clipping will occur (so thus distortion) because the max V is already attained at 5A. WIth ampB, will implement same fuse. If this amp go beyond 5A (burst mode) at 4 ohms, no clipping until it reaches 24.5V. In fact it can reach 5.5A (121W) at 4 ohms and not clipped!
The supply voltage, after you install the transformer, will now be constant: +/-20Vdc for ampA and +/-24.5Vdc for ampB.
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Will a power amp that doubles its power rating at 4 ohms sound better or of better quality than an amp doesnt double at 4 ohms?
TIA :)
With all else equal, YES. A power amp SHOULD ideally double its power output everytime you halve the load. It indicates an ideal linear behavour when presented with varying impedance loads across the audio frequencies. It also indicates a good adequate power supply that can deliver sustainable high enough currents for low loads. In fact a power amp that has a 2-ohm rating would have a better indication of its power handling abilities.
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omaygawd!!! :o :o :o ... But my fuse is slow blow ::) ;D ;D ;D
You are correct, if my fuse is fast blow, this will trigger the protection mode of the amplifier.
Ang daya! I thought 5A is your Imax (as in max) :D
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LOL, I am getting dizzy trying to understand the figures.
Thanks for the reply guys. :)
I plan to use it for 4 ohm speakers (w/c claim a linear impedance, doesnt dip much) .
Just wanted to know if the build quality of amps that double are better than those that dont. didnt expect figures :D.
Anyway, if all amps sound the same, Does it mean that you can use them for HT & audio whatever way they were constructed? Is there such a thing as an amp built for HT or an amp built for audio?
TIA again.
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Ang daya! I thought 5A is your Imax (as in max) :D
sir, even at 5A, 5A-slowblow-fuse, at short burst, it will not blow!
Let me summarize:
ampA
bias: +/- 20V
W at 8ohms: 50W (Pmax at 20V = 50W)
W at 4ohms: 100W (Pmax at 20V = 100W; dynamic)
ampB
bias: +/- 24.5V
W at 8ohms: 75W (Pmax at 24.5V = 75W)
W at 4ohms: 100W (Pmax at 24.5V = 150W; dynamic)
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LOL, I am getting dizzy trying to understand the figures.
Thanks for the reply guys. :)
I plan to use it for 4 ohm speakers (w/c claim a linear impedance, doesnt dip much) .
Just wanted to know if the build quality of amps that double are better than those that dont. didnt expect figures :D.
Anyway, if all amps sound the same, Does it mean that you can use them for HT & audio whatever way they were constructed? Is there such a thing as an amp built for HT or an amp built for audio?
TIA again.
As mentioned before, the only differentiator now in (forcing differences in) amps sounds are those DSPs, DACS, and pre-amp sonic implementations - they are not the 'power amps', however, some AVR and integrated have this already at your disposal. I wonder if any manufacturer already label a "power amp" only for HT or only for music.
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With all else equal, YES. A power amp SHOULD ideally double its power output everytime you halve the load. It indicates an ideal linear behavour when presented with varying impedance loads across the audio frequencies. It also indicates a good adequate power supply that can deliver sustainable high enough currents for low loads. In fact a power amp that has a 2-ohm rating would have a better indication of its power handling abilities.
Agree! The linearity is only dictated by the ampacity of the transformer. If the transformer can not deliver on ampacity, chances are, the voltage sag will be too much as to effect non-linearity in power output (again, if all other factors are held constant) when impedance (speaker load) changes ... with some parameters given, it is easy to choose and determine the better amplifier (spec-wise ;D) - objective lang ha!
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Napapansin ko lang...
audio amp (warm):
low DF
unregulated PSU
HT amp (crisp, clear):
high DF
regulated PSU
What do you guys think?
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Napapansin ko lang...
audio amp (warm):
low DF
unregulated PSU
HT amp (crisp, clear):
high DF
regulated PSU
What do you guys think?
Are you sure HT amp has regulated PSU? But I can only think only the DSP and pre-amp circuitry is regulated in the HT amp! Typically, the same is true with integrateds!
With the DF, am ignorant on its sonic effect!
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Are you sure HT amp has regulated PSU? But I can only think only the DSP and pre-amp circuitry is regulated in the HT amp! Typically, the same is true with integrateds!
With the DF, am ignorant on its sonic effect!
Ibig kong sabihin/itanong/i-verify, maganda raw ang unregulated sa mids? For tight bass naman daw, regulated?
I did not say that HT amps have regulated PSUs.
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Ibig kong sabihin/itanong/i-verify, maganda raw ang unregulated sa mids? For tight bass naman daw, regulated?
I did not say that HT amps have regulated PSUs.
When I am deep into the LM3886 pit, the findings is dependent on how good you are able to bypass the PSU impedances as not to interact with the amp output of audio spectrum.
Thus, a certain carlosfm provide the bypass strategy for both regulated and unregulated PSU. regulation has nothing to do with the sonic character. However, the regulated can hold the bias V constant(provided the design take into consideration the power sag before regulation), with unregulated, the voltage sag should be dealt with properly. This sag can really affect your bass expectation at loud passages.
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do power amps sound the same? of course not!
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Will a power amp that doubles its power rating at 4 ohms sound better or of better quality than an amp doesnt double at 4 ohms?
TIA :)
no, not really, what that buys you is a more robust amp, one that does not clipp earlier than the ones rated for just 8 ohms...
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no, not really, what that buys you is a more robust amp, one that does not clipp earlier than the ones rated for just 8 ohms...
... you got me there!!! it does not tell how 'better' it will sound ... it is just specs, and clip telling ... :) ... and better quality has to be qualified
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So a better quality amp will usually sound better right? Like in HT receivers, I have tried the entry levels & higher models of the same brand, they definitely DO NOT sound alike... in my ear's opinion. :)
Will higher powered amps sound better?
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So a better quality amp will usually sound better right? Like in HT receivers, I have tried the entry levels & higher models of the same brand, they definitely DO NOT sound alike... in my ear's opinion. :)
Will higher powered amps sound better?
Sorry master,
in as much as I want to agree with you, probably 10 years ago I could :), I have to qualify much before we deal what sounds better.
what is a 'better quality' amp to you? - to make this discreet: can you tell me which is better quality to you - a T-amp or a Konzert AV-502A amp?
T-amp: plastic casing, spring-loaded speaker connector, volume control, weighs more or less than 500gms, 7wpc into 8ohms, cost 2k, AA battery power supply, etc
Konzert AV-502A: metal case, standard speaker connector, all controls, weighs probably 5kg or more, 100Wpc (8 transistors yata), cost 4k, torroid PSU, etc
From your music materials down to the room where your speakers are fired, contributed to the sounds you are hearing (including your ear: inclination to your sound) ... a change in the amplifier in that system will not tell you whether the amplifier new is good or bad in itself ... at best, you could say that the amplifier sounds worse than the previous amp in your setup (Let me give you a sample below to illustrate the point)
.... a good rotel amp is a good amp ... a tono pre-amp is a good pre-amp ... when somebody experimented to let them join together, the sound sucks ... now you have to make your choice ... if you love rotel than the tono, you will say tono sucks ... or vice versa, if you love tono, rotel sucks ... further, if you have a cheapy pioneer amp joining tono producing the sound you like, apparently, it is easy to say the cheap pioneer amp is better than rotel (which you may be guilt stricken to do so because of the price of the rotel) ... the truth here is that some synergetic issues are at play ...
Thus, going back to your entry-level HT and high end HT (of the same maker), you are probably right ... but that is, taking into consideration what you have built around the HT receiver ... if you have chosen low sensitivity speakers, then power will matter at a certain point where the high end alternative may sound better and the entry level will be engaging overload conditions ... whereas if you have high sensitivity speakers, power will not be an issue between entry-level and high-end level ...
of course there are other things that you pay your high end receiver for ... build quality, protection, vanillas and candies ... but I can only invoke what I read from the HK web site: price has nothing to do with sonic characteristics (sounds better) of an audio gear! ... In fact, even what sounds better is a highly debatable thing! ... probably we should talk about 'What measures better?'
Note, I did not try to answer your first question (what is the measure of better quality amp?)
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Is there such a thing as an amp built for HT or an amp built for audio?
NO, the amps would not know which system they are used on, only you know that...they should be good for both... ;D
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To those who want to exercise ... I may be wrong here ... feel free to point it out ...
Lets design a 75W/8ohms
The bias voltage I need should be: P=V^2/R = 75W = V^2/8ohms : V^2 = 600Vsquare
This will give me about +/-24.5Vdc.
However, based on previous computation, I only need +/-20Vdc to accomplish 100W/4ohms.
Let's see the current:
I = P/V = 75W/24.5V = 3.06A to accomplish a 75W/8ohms
Again, to accomplish 100W/4ohms, I only need 5A.
The difference of this amp to the previous amp is only the bias voltage I have to implement! Here I need same power supply that can handle 5A but with tap voltage equivlent to +/-24.5V. The PSU of previous amp can only handle P=VI=20V*5A=100W max (simple computation for presentation only), while this amp transformer can handle P=VI=24.5V*5A=122.5W
And with this bias voltage, my amp can kick at 4 ohms about :
P = V^2/R = (24.5V)^2/4ohms = 600/4 = 150W (dynamic power burst) giving me 150w (dynamic power)/100w (rated power) of about less than 3db into 4 ohms.
(This is with the assumption that both amplifier were limited with those computed bias voltage, which in real life is more than that because of ac/dc conversion factors).
further explanation is needed here, so with aHobbit's kind permission allow me to elaborate in relation to real power amps. btw, aHobbit's analysis is applicable to both solid state and tube amps....
also, aHobbit's analysis assumes sine waves..
now, in terms of ac voltage 75watts into 8 ohms translates to 24.5 volts, this is rms value, from here we can get the peak value, which is 34.3, so the peak to peak value then is 68.6 volts.
we consider output transistor clipping, we dont want that so therefore we allow about 4 to 8 volts, say 8 volts, we add that to our peak to peak value and so we have 76.6 volts,
then we consider power transformer regulation, say we add another 10volts, so now we have 86.6 volts,
so our amp then will have a supply voltage of 86.6 volts, are you still with me?
our power amp will have around 90volts of B+ unloaded.
modern amps uses split power supply in order to do away with the output blocking capacitor, so now we just devide 86.6 volt by 2 and we have 43.3 volts, the nearest standard value of filter caps is rated 50v working dc, but i will choose one rated for 63 volts to be on the safe side.
why would you want to know this?
so that the next time you open up an amp, you will have a good guess right there and then about the amps' capability in terms of power.
this is just a start, but it will help, especially when presented with an amp that claims to put out several hundred watts.
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So a better quality amp will usually sound better right? Like in HT receivers, I have tried the entry levels & higher models of the same brand, they definitely DO NOT sound alike... in my ear's opinion. :)
Will higher powered amps sound better?
wrong, a well designed amp will always sound better, like Krells, Leach and Pass amps. and the amps need not be expensive. that is why DIY is resorted to, while i never built a Krell or a Pass, i built a lot of Leach's amps and i would say they are quite good to my ears.
i built a 4way speaker system with 15inch woofer, a 12 inch low mid, an 8 inch high mid, and an array of dome tweeters. and boy, "Hotel Calirfornia" never sounded so good...this was in the early 80's...well, until i met the Bose 801's, but thtat is another story...
i like the sound of my AIWA component, it never fails to thrill me....in my ear's opinion... ;D
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Will higher powered amps sound better?
If you are listening to a 20wrms per ch amp driven at its rated power, you'd be very close to or already at its clipping point. So an amp rated at even 30wrms per ch at the same wattage level should sound better, since you'd have some more headroom for undistorted or less-distorted peaks, all else being equal or close to equal. I won't put much weight on rated dynamic power, though that will help. Defintely if the 20wrms amp has a dynamic headroom of 3db, that might even be better than the 30wrms amp with no dynamic headroom. But personally, I just use RMS rating for my guide, realising that the measurement techniques for dynamic power is not a standard thing.
But for sure, if you are just listening at your comfortable levels of 20wrms per channel, I can't say a 120wrms amp will sound any better than a 70wrms amp. All else equal.
So if you like listening at close to the amp's rated power, in general, a higher powered amp should sound better. That's when power heardroom starts to matter.
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no, not really, what that buys you is a more robust amp, one that does not clipp earlier than the ones rated for just 8 ohms...
If I recall right, there's more probability an amp that can't double it's output power when the load is halved can also exhibit poorer damping and slew rates than one that does. Apart from being current challenged.
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...applicable to both solid state and tube amps....
...why would you want to know this?
so that the next time you open up an amp, you will have a good guess right there and then about the amps' capability in terms of power.
this is just a start, but it will help, especially when presented with an amp that claims to put out several hundred watts.
:D :D :D
am dead sure more heads got dizzy!!! ;D ;D ;D
I tried to avoid all those other considerations for simplicity of presentation ... but you did it anyway ...
... not only the above reason can be of help validating amps claims ... you will also know whether those hypes, e.g. high current capacity et.al., holds water by using the above computation and correlating all those specs that you read into what the amp was actually built upon ...
NO, the amps would not know which system they are used on, only you know that...they should be good for both... ;D
Indeed!!! ;)
...
i like the sound of my AIWA component, it never fails to thrill me....in my ear's opinion... ;D
...
Unknowingly, am still looking at the built factor sometimes to judge how it will sound (when will I ever learn!!! ;D) ... My jaw just dropped when incidentally I hooked a Technics amp to my Coral FR!!! :o Sound has never been the same ... to my ears (of course) ;D
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If I recall right, there's more probability an amp that can't double it's output power when the load is halved can also exhibit poorer damping and slew rates than one that does. Apart from being current challenged.
very true, specially in commercial amps where the primary concern of amp manufacturers is to make a profit...
the reason is because the transformer used is not based on power capability alone, they factor in the probable average home use and come up with economical size for the transformer, makes perfect business sense to me.. ;D
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A bit OT:
It may also worth noting the nature of the music one is playing. Michael Mardis (T-amp guy) has a very interesting article on this on his site. Classicals are the most dynamic, as I recall, recorded at -22dB from peak. If I understand it correctly, given 100W before clipping, we can't go more than 0.63W for the quietest passages else, we'll force the amp to clip when the music peaks.
Gain, I believe, also plays a big role regarding clipping. So watch out for that volume control.
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very true, specially in commercial amps where the primary concern of amp manufacturers is to make a profit...
the reason is because the transformer used is not based on power capability alone, they factor in the probable average home use and come up with economical size for the transformer, makes perfect business sense to me.. ;D
That mostly likely accounts for why there is such a thing as mass-fi and mid-fi amps to distinguish them from true hi-fi gears that have a lot fewer design compromises, if at all.
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That mostly likely accounts for why there is such a thing as mass-fi and mid-fi amps to distinguish them from true hi-fi gears that have a lot fewer design compromises, if at all.
technically speaking ... even if transformer rating have been compromised ... all of them are considered hi-fi ... they only differ in their design objectives (how much of a THD we will tolerate, how much impedance to support, how much of this and how much of that) ... typical of amp building ... some may exagerate demands of the surround ... some underestimate the use of surround ... thus they will have different attack ... at the end of the day, all of them, including those who ;D "never" ;D tolerated design compromises, are after profits the easier way - only different in getting them!
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Gain, I believe, also plays a big role regarding clipping.
gain is just the ratio of input voltage to output voltage. it is the power supply that determines which amps clipp earlier than the others, that is why i am on the belief that you can use a 200 watt amp even if you will just be listening at a 2 watt level most of the time, it is the dynamic range that is at stake here.
as i have shown earlier in my post, a sine wave will have a peak to average ratio of just 2, whereas, music has more than 10.... ;D
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technically speaking ... even if transformer rating have been compromised ... all of them are
considered hi-fi ... they only differ in their design objectives (how much of a THD we will tolerate, how much impedance to support, how much of this and how much of that) ... typical of amp building ... some may exagerate demands of the surround ... some underestimate the use of surround ... thus they will have different attack ... at the end of the day, all of them, including those who ;D "never" ;D tolerated design compromises, are after profits the easier way - only different in getting them!
I have too much respect for high fidelity to accept that all amps are hi fi. Technically or otherwise. The word compromise is too much an indictment of any design objective that makes high fidelity a joke - just another label to attract sales. All I'd say is that above a certain set of specification, or above some acceptable level of compromise, I can say the amps conform to the standards for it to quality as hifi. But below it, they can't be called hifi.
I can understand your point about the profit motivation of commercial amps. Yes, they all aim for profits, that's a natural business predication. But even so, there's always such a thing as good products and not as good products.
That is why there's such a thing as informed DIY and modding. Because a dedicated and well-informed hobbyist knows that true high fidelity can seldom be achieved with crass commercialism. Those appliances that do are often entirely beyond acceptable affordability that it behooves a seasoned hobbyist to make a amp that renders the word Compromise nearly immaterial but which he can do at a more reasonable investment, albeit with more time and effort. That's my view. Feel free to look at all amps as hifi. Not me.
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Feel free to look at all amps as hifi. Not me.
Its not me either! ;D
I just borrowed the following phrase: "GO the usual brands nowadays: Marantz, yamaha, HK, Denon, onkyo, and you will be in the right track! They are all hi-fi!"
... of course, I agree!
All amps are a compromise ... you just need to know (your applications) when not to activate these compromises ... so you build your setup accordingly ... uncompromised hi-fi? am in no fantasy land! ... even DIYers knew this! choose your compromises, build it, and live with it!
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But even so, there's always such a thing as good products and not as good products.
you bet, the guys at "surplus amps" sandawa et al, are well aware of it...and they are laughing all the way to the bank... ;D
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you bet, the guys at "surplus amps" sandawa et al, are well aware of it...and they are laughing all the way to the bank... ;D
:D :D :D
I like them ... there is always gold in the trash ;D ;D ;D ... it depends on who's looking ... and what to look for!!! :) ... err, I want to hang those works of art in the wall ... stop me, I want to buy more :D :D
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OT....some quotes around the corner...
"one man's junk is another man's treasure..."
"i like things that won't get you broke and make fun. i only buy second hand..."
" tubo tubo ka jan, ilang surplus na katapat nyan..."
"huwag eengot engot, else ma rip off ka jan..."
" this is just a hobby, dont be too serious, else you go into audio neurosis..."
" an audiophile listens to his gears, a music lover appreciates the music..."
;D ;D ;D
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" an audiophile listens to his gears, a music lover appreciates the music..."
;D ;D ;D
Strange, I always thought Audophile is just another word with Greek origins that mean the same thing as Music Lover. ;D
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OT....some quotes around the corner...
"one man's junk is another man's treasure..."
"i like things that won't get you broke and make fun. i only buy second hand..."
" tubo tubo ka jan, ilang surplus na katapat nyan..."
"huwag eengot engot, else ma rip off ka jan..."
" this is just a hobby, dont be too serious, else you go into audio neurosis..."
" an audiophile listens to his gears, a music lover appreciates the music..."
;D ;D ;D
:D :D
When I am a hobbyist, I listen to the sound ...
When I am relaxing, I listen to the music ! ;D