Topic: Considering a Tube Amp

[CoolTOYZPH]

Sir not for sale, for trial only. I am no longer in audio trading.

How it sounds at home is always different from the sound at the dealer... 😊

[JojoD818]

Some questions, if you don't mind:

I plan to build my speakers on a Fostex FE126En (will order and ship thru Forex).  I'm thinking Frugel-Horn MarkIII(http://www.frugal-horn.com/FH3.html) is simple enough to build.  But there's also the Olson-Nagaoka (http://www.frugal-horn.com/spawn.html) cabinets.  Suggestions?

I am limiting my amp selection to 15W because the Fostex is rated at 15W input and SPL of 93db.  My listening room will be enclosed and quiet so I don't need all that oomph.  Am I right in this matching?

• Are the words sensitivity, efficiency, and SPL equivalent?
• What output power should I specify for the amp given a certain input power rating of my drivers?

The FH has a longer horn length than the ON, however the ON has a wider horn mouth than the FH. For the novice it is going to be a nightmare choosing which one. But personally, I'd vote for the Frugel build. Or, being a master woodworker, why not build both? Just teasing.

 Do not limit your amp selection by virtue of output power. You can use a 100W amp for a 10W speaker. Your fingers will be the limiter here so you don't overdrive your speaker. Besides, using a high power output amp gives you more dynamic headroom, whilst a low power output amp will tend to compress, this compression is where tube amps are king... and is the very science/reason why they tend to sound "louder" than their SS counterparts.

No they are not the same. Sensitivity denotes an SPL number based on a given input power. Efficiency is the manner in which the speaker/enclosure combination translates a given input power into SPL. Finally, SPL is a measure of the converted signal.

Output power of amps are quite trivial, I'd suggest you look at it this way. A speaker with high sensitivity requires far more little from an amp while a speaker with medium to low sensitivity will ask a bit more to reproduce the same amount of energy. This difference is the more important factor to consider in choosing an amp, it must be able to deliver a bit more in case it is needed, or it will compress. Compressed music is lifeless.

[JojoD818]

Ding,

This may help you understand it easier....

If you have a piece of hardwood, say a 2x4 and you want to round over an edge. A 250W trim router will surely work right? But a 3 horse power monster of a plunge router will be better.

Cheers

Jojo

[JojoD818]

Ding, amx amps are value for money talaga and tama ka buy Pinoy made is the best. Ikaw na gumawa ng cabinetry. I also think he can do that st-70 kit for you, or maybe jojo

Sorry pare, pass muna ako.

[ricky]

Jo huminga ka naman KASI minsan hahaha.

[JojoD818]

Jo huminga ka naman KASI minsan hahaha.

Humaba ng husto pila eh.

Seriously, 2017 na pare... game na!

[nelcarol1994]

Dami pala mangkukulam dito!

Tony mentioned Andrew Sevilla.  Got in touch with him when I came across his name in some thread, too, and got his number from Ricky (Thanks!).  We traded several text messages and it's exciting.

He recommended an EL34 Single Ended Amp, 10W/ch, 3 line inputs.  Well within budget.  Extra if I wanted it pimped out.

I'm leaning towards having it done by Andrew.  Aside from being cost-effective, there's the certain pride in having a Filipino designed-and-made excellent amp.  Only problem with this approach is that I don't get to hear before I buy so I will just have to rely on what people say about his work.

@Tony
Still in love with the Sakura.  But the selector switches and volume knobs are starting to act up.  Need replacing.  I think I stowed have some good pots somewhere and will just have to source the selector switch (Deeco?).  But I'd rather tinker with wood for now than soldering; unless I stumble into a cheap ST-70 kit.  Know anyone who can do this for me?  Or soup it up?

@CoolTOYZPH
Thanks very much for the offer! Hiya naman ako manghiram.  I think Hi-Fi is also your business(?) so I would hesitate to take advantage of your generosity without a commitment of sale.  How about if I drop by your shop and hear your goodies there?

Some questions, if you don't mind:

I plan to build my speakers on a Fostex FE126En (will order and ship thru Forex).  I'm thinking Frugel-Horn MarkIII(http://www.frugal-horn.com/FH3.html) is simple enough to build.  But there's also the Olson-Nagaoka (http://www.frugal-horn.com/spawn.html) cabinets.  Suggestions?

I am limiting my amp selection to 15W because the Fostex is rated at 15W input and SPL of 93db.  My listening room will be enclosed and quiet so I don't need all that oomph.  Am I right in this matching?

• Are the words sensitivity, efficiency, and SPL equivalent?
• What output power should I specify for the amp given a certain input power rating of my drivers?

Try to consider also audio nirvana full range speaker from commonsenseaudio.com


Sent from my iPad using Tapatalk

[balarila]

Sir not for sale, for trial only. I am no longer in audio trading.

How it sounds at home is always different from the sound at the dealer... 😊

My apologies then.  I assumed you had commercial intentions. Really appreciate this.  People like you make this forum a lot lot nicer.

Call!

I will be in a meeting in Makati on Thu late morning so, on way back, maybe I can meet up where comfortable for you.  PM na lang tayo.

Salamat and Merry Christmas!

[balarila]

@Tony
Many thanks for the tips.

@Jojo
Your explanations are crystal.  That router analogy was the homerun.

@NelCarol
Heard about Audio Nirvana for some time now.  Will google it.


This is probably one of the coolest looking amps I've seen.

Made by Andrew.

It's a 300B and costs more than double the EL34 but both are 10W.  Here's the idiot question:  What's the difference?  Should I hold out for the 300B?


Merry Christmas!

[tony]

You can use a 100W amp for a 10W speaker

very true.....and in my case, i stopped counting the watts altogether,
for as long as your amp can drive your speakers to your liking.....

It's a 300B and costs more than double the EL34 but both are 10W.  Here's the idiot question:  What's the difference?  Should I hold out for the 300B?

only you can answer that......

[balarila]

only you can answer that......

Guess I should've phrased my question more clearly.  Why are 300B's considerably more expensive than EL34s or KT88s?  Do they last longer?  Do experts perceive they produce better sound?

[CoolTOYZPH]

Only Playing it Forward.
When I was starting with Tube Amps, fellow music lovers lent me their gears to allow me to experience the tube magic.

My apologies then.  I assumed you had commercial intentions. Really appreciate this.  People like you make this forum a lot lot nicer.

Call!

I will be in a meeting in Makati on Thu late morning so, on way back, maybe I can meet up where comfortable for you.  PM na lang tayo.

Salamat and Merry Christmas!

[CoolTOYZPH]

The 300B tubes are more expensive.
They do not last longer.
Each tube has their own flavor and it is really a matter of preference.
I am more of a 6550/EL-34 type.

Guess I should've phrased my question more clearly.  Why are 300B's considerably more expensive than EL34s or KT88s?  Do they last longer?  Do experts perceive they produce better sound?

[onedown]

try auditioning a 6550 or kt88 amp. designed right, you can switch between those tubes, giving you more options on tube rolling.

[tony]

Guess I should've phrased my question more clearly.  Why are 300B's considerably more expensive than EL34s or KT88s?  Do they last longer?  Do experts perceive they produce better sound?

i got you the first time....

it doesn't really matter what the experts perceive....
what must matter is what you percieve, you will live with your
decision, not the so called experts...

tubes used on a single ended type amp are operated
very close to their plate limits, because that is how they sound
their best.... and a shorter life can be the natural consequence...
but why worry over this? tubes are meant to die sometime,
they do not last a lifetime...
over time, the cathodes of the tubes gets depleted, and transconductance decreases to a point that renders the tube unfit for the application and so needs to be replaced...
unless you can accept this as a natural progression of tube life,
then stop.....

the push pull amp otoh are operated cooler and so can last much longer...

again, why more expensive? because of the hypes.....

[CoolTOYZPH]

You may also want to consider a Hybrid Set-up.
Tube Pre-AMP + Solid State Power AMP.
Benefits are:
1) LESS Maintenance on Tubes specially compared to Single Ended Designs
2) MORE options for speakers since Solid State AMPS may offer more power.

[tony]

Tube Pre-AMP + Solid State Power AMP.

sakura AV-200

[CoolTOYZPH]

Are the tubes in the SAKURA AV-200 designed more as a Tube Pre-Amp or Tube Buffer?

[balarila]

Thank you for all the advice/comments.  This is turning out to be a great Christmas, indeed.  Will have to remind myself to spend time with the family!

The reason I've been asking these questions (aside from being tube-ignorant) is that I am hesitating to audition now since my first choice is to go with Andrew's build (nationalistic and budget reasons) and auditioning elsewhere with little intent to buy is unfair to the commercial establishment.  Kinda like trying on clothes at the mall then buying it online.

I therefore would like to gain as much info from experiences of people here.  Of course, as Tony said, your ears and environment can be vastly different from mine.

Buti na lang hulog ng langit si Jojo (CoolTOYZPH) and he is lending me a EL34 amp.  At least, I get to experience somewhat what Andrew is recommending for me.

If I break down from my scruples, I may end up auditioning still, justifying it as providing the shop with an opportunity to sway me.

Meantime, research muna 'ko.  So many things to learn.  Don't even know what the amp classes are; just getting introduced to SET and push-pull; boning up on EL34, KT88, 300B.

[tony]

Are the tubes in the SAKURA AV-200 designed more as a Tube Pre-Amp or Tube Buffer?

anything before the power amp is a pre amp...
it can be passive like the tvc or plain jane pot,
a buffer or a line stage....

it all depends, some program sources are high enough
so that a passive preamp suffices...or a buffer...
if the program source do not have an output level
sufficient enough for the power amp, then use a line amp...
so horses for courses.....

[tony]

If I break down from my scruples, I may end up auditioning still, justifying it as providing the shop with an opportunity to sway me.

you have your fostex speaker and that is were we start....

your options are an el84 pp amp, or a single ended 6550/6l6gc/el34 which Andrew can supply you....
listen to both types, a pp amp and a single ended
and see which one sways you best....

[tony]

Heard about Audio Nirvana for some time now. 

marikina is just a stones' throw away from antipolo,
Jun, aka remington here owns many of those, he even has
an AMX el84 pp amp for you to audition....

but i must warn you, once you get to hear the Audio Nirvanas
and the el84 pp amp....you may end up dumping those fostex....
so be warned......

[balarila]

...but i must warn you, once you get to hear the Audio Nirvanas
and the el84 pp amp....you may end up dumping those fostex....
so be warned......

Don't have the Fostex yet.  Still to order.  So am a bit flexible there.

Reason I focused on them is because they seem to be a popular choice among DIYers at Frugal-Horn.  And I like the elegant approach of having a 4-inch driver produce beautiful sound.  Will check out AudioNirvana.  Would they also be suited for a FH3?

[JojoD818]

Depending on the genre and your perception of it, I'd vote for the Fostex. (<- EDIT: This is just a personal opinion based on personal experience.)

However, the Audio Nirvanas are frequent in the marketplace so you may check them out too.

[Nelson de Leon]

Don't have the Fostex yet.  Still to order.  So am a bit flexible there.

Reason I focused on them is because they seem to be a popular choice among DIYers at Frugal-Horn.  And I like the elegant approach of having a 4-inch driver produce beautiful sound.  Will check out AudioNirvana.  Would they also be suited for a FH3?

Those 4" full range drivers are very sweet in the mids. Kaya lang if you have a "kinda" loud listening level, it may not be for you.

[ricky]

Ding i can lend you set/sep amp using el34 driving a kefq1. Sounds nice pero namimili pa din ng type of music.

I mean pag vocals, very sweet sounding sya,pag pop naman not so good. Pag new wave bitin. So depende talaga ano gusto mo.

300b punchy sound pero ang mahal ng tubes nya (kasing laki coke solo)

Dont be discourage about changing the tubes, napakatagal naman ng buhay, yun kay mrs ginamit pa nya pang videoke and up to now ok pa.

Also diff brands of tubes on a single type can give you diff sound character(hindi masyado noticeable MINSAN) pero you can play along with it.

PP amps are mo flexible bec of the power , while set/sep na 8-10watts namimili talag ng speakers at music.

[ricky]

Ang masasabi ko lang , di hamak na magastos ang audio kaysa ht hahaha. You have been warned pare.

After the amps and speakers, yung source mo naman, cd, tt or hdd? Hi di pa natin pinaguusapan cables ha.

[JojoD818]

Ang masasabi ko lang , di hamak na magastos ang audio kaysa ht hahaha. You have been warned pare.

After the amps and speakers, yung source mo naman, cd, tt or hdd? Hi di pa natin pinaguusapan cables ha.

Medyo mahirapan si Ding pumili, lahat ng choices niya magaganda.

[tony]

Those 4" full range drivers are very sweet in the mids. Kaya lang if you have a "kinda" loud listening level, it may not be for you.

in our first outing at Dusit, Tony Rodriquez made use of a sony 4 incher full ranger in a line transmission box..it was powered by my pp el34 st70 clone....playing a joe morello take 5 cut, a guy approached me and asked me, sir, nasaan po nakalagay yung subwoofer nyo? he was fooled into thinking that we had a subwoofer in the room....

[balarila]

Ding i can lend you set/sep amp using el34 driving a kefq1. Sounds nice pero namimili pa din ng type of music.

I mean pag vocals, very sweet sounding sya,pag pop naman not so good. Pag new wave bitin. So depende talaga ano gusto mo.

300b punchy sound pero ang mahal ng tubes nya (kasing laki coke solo)

Dont be discourage about changing the tubes, napakatagal naman ng buhay, yun kay mrs ginamit pa nya pang videoke and up to now ok pa.

Also diff brands of tubes on a single type can give you diff sound character(hindi masyado noticeable MINSAN) pero you can play along with it.

PP amps are mo flexible bec of the power , while set/sep na 8-10watts namimili talag ng speakers at music.

Call!  Kaya lang we live in different galaxies.  Meet up may be difficult.  Try ko muna yung kay Jojo.  Pag bitin pa, will call you.  Salamat!