Topic: 1% THD of Pioneer Receivers

[JojoD818]

I started this thread and i dont intend to defend the PIONEER product i own and maybe all the other audio equipments i have. In fact i also own a Denon and a Yamaha. My only intention is really to understand this 1% THD issue which have been frequently mentioned in many of the threads here. -- 

Well, I hope you have learned something. 

[JojoD818]

He's just arming everybody with knowledge that may help someday.

This is what I was doing ever since I joined this thread. To give accurate understanding of THD for everybody.

More music,
JojoD

[aHobbit]

This is what I was doing ever since I joined this thread. To give accurate understanding of THD for everybody.

More music,
JojoD

Yo! 

Now we know THD. 

Now we know different regulations. 

And some think they know better than those who established regulations and better than those that followed the regulations.   

And I think when they spotted the same product rated with a different regulation, they still won't believe. 

Ayoko na! na! na! na! (echo ito)    Paiba-iba ng tema. Paikot-ikot na depensa.

[aHobbit]

He's just arming everybody with knowledge that may help someday.

I hope that ARM is not AIMED at you! 

[jacorb88]

from unknowing customer like me, i call this marketing hype. they maybe telling the truth but what they do is to package their product in such a way that it would look more attractive to customers not equipped with knowledge like most of you have. fortunately for the manufacturer, greater percentage of their customers don't pay attention to details and fall prey to this hype.

before i joined this forum, i'll always look at the power rating. Higher number the better. Other details are just an added bonus. Boy, I was wrong!!!

[arthurallanj]

from unknowing customer like me, i call this marketing hype. they maybe telling the truth but what they do is to package their product in such a way that it would look more attractive to customers not equipped with knowledge like most of you have. fortunately for the manufacturer, greater percentage of their customers don't pay attention to details and fall prey to this hype.

before i joined this forum, i'll always look at the power rating. Higher number the better. Other details are just an added bonus. Boy, I was wrong!!!

Alas! Haaay Salamat!!!! Ditto. Finally, somebody finally got it, right Sir AV?

[akyatbundok]

let's see how different manufacturers disclose the specifications in their brochures:

Brand A)  stereo continuous ave. power (FTC): 65W/ch, 20Hz-20kHz @ <0.07% THD, both channels driven into 8 ohms
- hmmmm, all necessary info are disclosed.... hooray for Brand A !!! 

Brand B) power output: 90W/ch (8 ohms)
- minimal information, no disclosure on THD, continuous or maximum, freq. range, which channels driven, etc. nada. 

Brand C) maximum output power (8 ohms, 1kHz, 10% THD): 135W x 7
- all channels driven, but just the maximum power at 10% THD !!! 

Brand D) stereo power: 100W/ch (L/R, 20Hz-20kHz, 0.03% THD, 6 ohms)
- almost there, but it doesn't say if continuous or dynamic

guess what, they all actually sound pretty good, and the numbers don't indicate if one unit sounds any better than the other..... if there's anything the numbers tell me, its that you can't use the specs for comparison, unless within the same brand...... fact is, among these 4 receivers i would probably buy C if i already have a separate amp for audio, B if leaning more on audio, and A for mixed HT & audio.

if only the power ratings were measured under the same conditions....

[losi_phile]

I have an actual experience of what akyatbundok illustrated.

13 years ago, my brother-in-law gave me, as a wedding gift, a Sony Mini-compo with the following rating : Speakers - 6 Ohms; Power Consumption - 220Volts, 60Watts.  That's all.  Used it for more than 10years.

Year 2000, I was able to buy (sa isang surplus shop) a Pioneer AVR - VSX-D509S with the following specs: 8 Ohms; 100Watts with no more than 0.2% THD (per FTC standard) 2 Channels driven.  Forgotten my Sony mini-compo at hinayaang maalikabukan.

Year 2003, yearning to have a stereo only set-up. I bought a surplus integrated amp, Sansui Alpha-607U, don't know the specs but I guess better than Pioneer AVR.

3 or 4 months ago, somebody told me to use my sony mini-compo to drive my diamond 8.3.  Whoa!!! what a sound!!!!  So here's what happened to my other gears: Sansui Alpha-607U - used as pre-amp na lang ng turntable ko;  Pioneer AVR - surround and center channel amp, subwoofer pre-amp when watching movies. 

My sony mini-compo beat my two other gears (Stereo listening-wise) and I don't even know its THD!

There's more to music than your amps THD rating, for me.  Jungle Bells ,Jungle Bells, Jungle Bells All The Way

I hope we refrain from using the words "HPYE", "HYPING"; "UNTRUTHFUL" in this thread.  I guess nobody deserve to be called by such terminologies.  Manufacturers just adhere to the standard set by certain governing bodies at kung hindi, baka maraming nang nademandang company for telling other things aside from that mandated by the law.  Pero so far wala akong alam na nangyari ito.  If you want to know the "real" specs of the gear you're about to buy, why not just call the technical department of the manufacturer and ask them the real score if you still don't believe or have doubts on the specs written in their manual.  Mas matrabaho nga lang pero at least alam mo na hindi ka magogoyo pagbili mo.  Ako lang naman ito.

[aHobbit]

guess what, they all actually sound pretty good, and the numbers don't indicate if one unit sounds any better than the other..... if there's anything the numbers tell me, its that you can't use the specs for comparison, unless within the same brand......
 

 

Have I seen you from the new school? 

Let's have a toast . . . of gulaman! 

Performance can only be known by real-world listening and testing. I must admit, relying too much on (THD, para di OT  ) specs and judging with just (THD, ayan dalawa na para lalong hindi OT  ) specs (even for first level ellimination of options), are for beginners.

I dedicate posts below to all my classmates who learned the art of evaluating true "audiophile"  performance!  (with due respect to Rotel, Adcom, tube amps - no personal pugn intended - quoted verbatim). Everything is opinion, be the judge.

From LeBob of Alabama -
Comparing this (TDA7384) amp to my tube gear, no compromise SE 2A3, 6V6 SE and 2A3 PP, and two vintage PP tube amps, this amplifier is really quite amazing; serious bass, good high frequency extension, and very fast transient response... I can say without doubt that it sounds much better than a newer 135 watts per channel Rotell solid state amp I compared it to using the same speakers and source. ...

A friend from school who is working with me on this project came to my house to listen to the amp. He says his new Adcom may be on Ebay very soon.


From Carlos of Portugal -
... I made a small amp with OPA548 chips and two single voltage 15V/3A trafos for a friend of mine. He compared my (his) small amp with a shiny new 5-star rating Rotell 1062 integrated amp on a demo room, with expensive B&W speakers. It was clear that the little amp had a level of detail and faithfulness to the music that the Rotel could only dream of.

[JojoD818]

I hope that ARM is not AIMED at you! 

 

[av_phile1]

in fairness to the brand and model being mentioned in this thread, let's all take notice of the fact that Pioneer is not the only manufacturer that discloses output power at 1% THD, and that the VSX-D811 is not the only receiver model that has disclosed specs at 1% THD.

i search google for "1% THD receiver" and i see pioneer, kenwood, sony, yamaha, panasonic.... even "10% THD" yields results.

Yup, pioneer is just one of them.  Seems a lot of Japanece products for the mass market do.  I really couldn't care any less why.  All I know is that if the power measurement is done at higher THD levels, the higher the numbers on power can be obtained.  It's that simple.  In another forum, somebody opined that the mass market playing field has never been even - a problem that the FTC tried to address.  And in that market, it's all a power numbers game for most unwary consumers.  That's another reason for those PMPO banners on 10,000watts. 

[av_phile1]

let's see how different manufacturers disclose the specifications in their brochures:

Brand A)  stereo continuous ave. power (FTC): 65W/ch, 20Hz-20kHz @ <0.07% THD, both channels driven into 8 ohms
- hmmmm, all necessary info are disclosed.... hooray for Brand A !!! 

Brand B) power output: 90W/ch (8 ohms)
- minimal information, no disclosure on THD, continuous or maximum, freq. range, which channels driven, etc. nada. 

Brand C) maximum output power (8 ohms, 1kHz, 10% THD): 135W x 7
- all channels driven, but just the maximum power at 10% THD !!! 

Brand D) stereo power: 100W/ch (L/R, 20Hz-20kHz, 0.03% THD, 6 ohms)
- almost there, but it doesn't say if continuous or dynamic

guess what, they all actually sound pretty good, and the numbers don't indicate if one unit sounds any better than the other..... if there's anything the numbers tell me, its that you can't use the specs for comparison, unless within the same brand...... fact is, among these 4 receivers i would probably buy C if i already have a separate amp for audio, B if leaning more on audio, and A for mixed HT & audio.

if only the power ratings were measured under the same conditions....

Under normal comfortable listening conditions in a typical room, you would hardly go beyond 5 watts per channel, so that all those amplifiers sound about the same at that level.  They could very have the same amplifier circuit topologies, the same linear operating characteristics, the same NFB circuits.  But they are rated differently using different measurement conditions.  One could be rated at 0.1% THD, the other at 10%THD.  One could be rated with ALL channels driven, the other with only 1 channel driven.  One could be rated only at 1Khz, another at full bandwidth.  All these measurement conditions will yield different power numbers for even the SAME amp.  But I can safely bet which one will be most interesting to marketing officials who would want to gain more market shares. 

Power ratings among respected brands under the FTC rulings have always had a level playing field.  THis has been taken for granted for so long among seasoned audiophiles.  So that it is fairly a no brainer to compare the specsheets of a Krell with a  Meridian with a Bryston or with a Musical Fidelity, a Rotel, an HK, et, etc.  Not just within the same brand.     We rarely dwelt on the subject of THD as most of these brands trumpet THD, IM and TIM levels well below 0.1%.  Every amplifer will try to outsell each other with the LEAST THD numbers and with the MOST power figure.  But it seems receivers these days have their own agenda.

[eaferrer]

Total Harmonic Distortion?  THD

Ill go for the TDH.

Totally De Hydrated na ako sa mga nabasa ko sa forum na ito! hahahahaha

[jerix]

La nabang hihirit dito?--

maidagdag ko lang po, ----- if all our audio equipments have their own THDs, is there a way to compute the sum total of THDs comin from all these gears when all the signals that passed through the gears have already been transformed into a sound signal? 

[av_phile1]

I think you simply add them up.   0.02% from a player + 0.02% from the reciever = 0.04% total.  If you know the THD of your speaker, then just add it. 

[jerix]

oK--- bro av_phile1,  we just have to add up pala.

I understand that as the Amp's volume is increased, so with its THD. The speaker's reaction is dependent upon the signal it gets from the amp. Does its THD also increase proportionate to the signal it receives from the amp? Now, if the amp gets signal from a source, such as a CD player, does the THD of the player increases too? thnks again ..

[arthurallanj]

Sir Av,
Question! Kahit ba digital signals may THD din? Or lesser sya? Kasi I've seen it dati on cable, just forgot the show, that if digital signal na daw and optics na ang ginagamit, lesser ang distortion. Thanks. 

[av_phile1]

THD is an anomaly in the analog domain.  No such thing in digital.

I can only guess that the show must be referring to radio broadcasting using analog-based fiber optic tranmission cables.  Distortion from AM and FM broadcasting using fiber optic cables often result in intermodulation and crosstalk distortions arsing from various signal carriers travelling on the same path. No such problem when using digitally converted AM and FM broadcast.  That is why digital AM and FM broadcast is superior in terms of fidelity.

[arthurallanj]

How about connections of dvd players to amps via optical cable? Is there a considerable amount of distortion coming from the source if it's connected digitally? Thanks Sir AV. God Bless.

[av_phile1]

None that I am aware of.  If the CD mix came from analog sources that had distortions to begin with, transcribing them to digital will also digitally encode the distortions. 

You may be alluding to NOISE as anything added to a signal that was not there to begin with distorts the signal.  It's possible, and in fact many players and soundcards do, that there is more considerable noise at the digital output than in the analog output.    In that case, you may be better off using the analog output than the digital route.  This is often an academic exercise as the THD+N figures obtained from a Fast Fourier Transform (FFT) test is more visible on the scope than audible in your system. 

[av_phile1]

oK--- bro av_phile1,  we just have to add up pala.

I understand that as the Amp's volume is increased, so with its THD. The speaker's reaction is dependent upon the signal it gets from the amp. Does its THD also increase proportionate to the signal it receives from the amp? Now, if the amp gets signal from a source, such as a CD player, does the THD of the player increases too? thnks again ..

Sorry for late response, had problems with the ISP last Friday. To your first question, in general, yes, my undrstanding is that the speaker's distortion rises with higher signal voltage fed into it.

Regarding your last question, I don't see how the CD player's THD will rise because of the amp.

[arthurallanj]

Thanks sir AV. 

[ment]

hi ....

medyo old topic pero me gusto lang po ako iclarify

if pioneer advertises "100 watts per channel at 1%THD" ..... what would be the correct wattage per channel for well below 0.1% THD? 90 watts?? 

[pabili]

hi ....

medyo old topic pero me gusto lang po ako iclarify

if pioneer advertises "100 watts per channel at 1%THD" ..... what would be the correct wattage per channel for well below 0.1% THD? 90 watts?? 

typically, half your power and your dead sure THD is way way below the 1%.

also note an important rule of thumb. 1% THD is accepted as the threshold of good amp design. The reason is that 1% THD is hardly recognizable by mere human hearing. This has been illustrated and proven in many listening challenge.

I have a kenwood mini compo, 80watts at 10% THD, but at 64watts at .04% THD (the specs provided it also).

Further, listening in a typical room is only from 1-10watts (typically loud na po ito - your neighbor may scorn at you na) depending on your speaker's sensitivity.

[ment]

thanks for this tip

[ATJr.]

typically, half your power and your dead sure THD is way way below the 1%.

agreed, the new thinking these days is that THD figures alone do not tell the whole story about an amp......rather the contents.....odd order harmonics, like the 3rd and so forth are offensive to the ears....wheras even order ones are not....so, depends on distortion spectrum, mere numbers alone is not sufficient.....tube amps have even higher distortion figures, and yet many are hooked on their sound.....

[pabili]

agreed, the new thinking these days is that THD figures alone do not tell the whole story about an amp......rather the contents.....odd order harmonics, like the 3rd and so forth are offensive to the ears....wheras even order ones are not....so, depends on distortion spectrum, mere numbers alone is not sufficient.....tube amps have even higher distortion figures, and yet many are hooked on their sound.....

yes sir. for solid state, 1% should be the max tolerable in paper specs (I really mean paper specs), but will not be an indication of good sound (same with those with THD below .1%).

Yes, the tube has more distortion, but as said by you, this distortion will not indicate that the amp sounds bad. Thus, this does not stop the inclination of many hobbyist going this route.

For other amp, they have specs up to 10% THD. But at half power, this amp is also clean at below .1% THD (like my kenwood amp). Of course, in some bad generic sellers, you should always have second thoughts - or I would say don't have it (second thought) at all. Just avoid them.

[jerix]

if you dont pump your amp to the specified power of 100w then the1%THD is nothing. 

Btw, nice to see this thread rollin again

[ATJr.]

yes sir. for solid state, 1% should be the max tolerable in paper specs (I really mean paper specs), but will not be an indication of good sound (same with those with THD below .1%).

Yes, the tube has more distortion, but as said by you, this distortion will not indicate that the amp sounds bad. Thus, this does not stop the inclination of many hobbyist going this route.

For other amp, they have specs up to 10% THD. But at half power, this amp is also clean at below .1% THD (like my kenwood amp). Of course, in some bad generic sellers, you should always have second thoughts - or I would say don't have it (second thought) at all. Just avoid them.

there is more....how the amp behaves when driven into clipping is also a good indicator of the quality of the amp...SS amps have the tendency to oscillate in the inaudible region when driven into clipping..that is the reason they get the bad rap....

there are two ways for the amp to clip, one is input overload, both signal amplitude and frequency can make the input stages of the amp to overload....then there is output overload, loading the amp with speakers it  can not drive well....

the thing is when using ss amps, don't play them at very high levels to avoid clipping....likewise, do not feed it signals that it can not handle..and don't connect too many speakers on the amp....

[jerix]

there is more....how the amp behaves when driven into clipping is also a good indicator of the quality of the amp...SS amps have the tendency to oscillate in the inaudible region when driven into clipping..that is the reason they get the bad rap....

there are two ways for the amp to clip, one is input overload, both signal amplitude and frequency can make the input stages of the amp to overload....then there is output overload, loading the amp with speakers it  can not drive well....

the thing is when using ss amps, don't play them at very high levels to avoid clipping....likewise, do not feed it signals that it can not handle..and don't connect too many speakers on the amp....

As faR as speakers connected to the amp is concerned, as long as it can handle them i think there will be no problem. My pioneer handles 2 sets of speakers in each of its 6 channels and i observe no distortion whatsoever even when i pump up the power to 10 db.