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synsei
17-01-2011, 23:07
I stumbled upon this fascinating 17 minute video which documents the making of a valve entirely by hand. I find it rather beautiful to watch, I hope you do too...

(The video clip is at the bottom of the page)

http://paillard.claude.free.fr/

Techno Commander
17-01-2011, 23:33
I have seen this before, but it always worth watching again. The guys skill is unbelievable. :)

selfaddict
20-01-2011, 22:18
This was great, I really enjoyed watching this.

kt66
24-01-2011, 17:38
it's VALVES not tubes!!

Reid Malenfant
24-01-2011, 17:45
it's VALVES not tubes!!
So please explain why changing valves for different but compatible types is known as "tube rolling" :scratch: Why not valve rolling?

:eyebrows:

Marco
24-01-2011, 17:49
Indeed - I think we (in the UK) are about the only ones in the world who refer to tubes as 'valves'.

However, linguistically, BOTH are correct :)

Marco.

Rare Bird
24-01-2011, 17:59
Indeed - I think we (in the UK) are about the only ones in the world who refer to tubes as 'valves'.

However, linguistically, BOTH are correct :)



Yeh but i could't see myself calling an old valve such as the VT121 a tube tbh!

synsei
24-01-2011, 18:47
Aren't you kinda missing the point here? :scratch:

Regardless of what you wanna call 'em, the guy is still an artist, semantics be damned...... :rolleyes:

I wouldn't have the patience to do what he does, but I appreciate the skill and dexterity he possesses and would happily spend an evening watching him do his thing... :ner:

Trickie_Dickie
25-01-2011, 13:26
That was bloody brilliant. 'cuse my french. Truly, an artist at work. :cool:

Trickie_Dickie
25-01-2011, 13:30
BTW, a tube is just that. (could be anything)
A valve controls the flow of something (in this case, electrons).

You pays yer money and takes yer choice, innit bruv. :cool:


Just an opinion of course.

Techno Commander
25-01-2011, 13:35
I believe the original term was "thermionic valve".

Then the Americans got involved ...........................
:)

Techno Commander
25-01-2011, 13:36
I guess thermionic was too complicated for them :D

Trickie_Dickie
25-01-2011, 14:26
I believe the original term was "thermionic valve".

Then the Americans got involved ...........................
:)

But they always come in late. :lolsign:

Trickie_Dickie
25-01-2011, 14:27
I guess thermionic was too complicated for them :D

Or maybe just the fact they can't spell. :lolsign::cool:

WOStantonCS100
26-01-2011, 00:57
Bloody bastages, why we should jump across the pond and bludgeon them with a rusty spanner!? Fine time to do it, innit bruv?

Oh, about the post... Shoot fire, dat dudes got away wit dem toobs! Whoooo wheeee!

synsei
26-01-2011, 01:58
Bloody bastages, why we should jump across the pond and bludgeon them with a rusty spanner!? Fine time to do it, innit bruv?

Oh, about the post... Shoot fire, dat dudes got away wit dem toobs! Whoooo wheeee!

:laugh:

WOStantonCS100
26-01-2011, 03:02
That really is a great video of a gent with an amazing amount of dedication. Thanks for posting it. It was good to watch it again. Someone probably told this guy, "...it can't be done..." and he didn't listen. :lolsign: The world needs more folks like that. :)

JazzBones
26-01-2011, 12:51
The only valves I've ever had/used are in a buffer stage (MF) and in my headphone amp (MF) but I guess they can't be classified as totally valves? What this is leading to is if a music enthusiast has used solid state all of his listening life, in my case earlier Naims (okay, I can feel it comin' at me :lol:), how can they be weaned off 'em and towards using valves without too much of a culture shock and a deviation to what he is enjoying at the moment ? :scratch: I have noticed that AoS is very much into Valves so much so I feel uncomfortable being here as a solid state user. I know that Martin T uses solid state amps so I don't feel all alone on this particular subject.
That copper amp that Marco has looks absolutely stunning and is a work of art in its own right, obviously it must sound extremely good too but it must come at a high price given the bespoke nature of manufacture?

Where would you valve/tube/ thermionics followers make a start from if you were sitting in my listening chair? I must say I have heard some good valve sounds at the various hi fi shows I've been to but nothing that would make me junk what I have carefully put together over the years but I am open to an education. I don't subscribe to SS/transitors being Satan's work as Noel Keywood leads me to conclude :rolleyes:

I need a convincing education into the world of valves, erm toobs, please;)

Ron

anthonyTD
26-01-2011, 13:23
Had this video on the front page of my website for a few years now, it impressed me that much!:)
Anthony,TD...

Marco
26-01-2011, 13:29
Hi Ron,

Are you genuinely thinking of going the valve route, or are you merely just curious about what 'toobs' might have to offer?

As a former 'Naimee' of many years, I came to valves from using a NAC52 and a pair of 'olive series' 135s, so I know just what the journey entails in terms of the sonic advantages and pitfalls...


I have noticed that AoS is very much into Valves so much so I feel uncomfortable being here as a solid state user.


You shouldn't do, as in reality, there are far more users of solid-state gear here than valves! ;)

It's simply a matter of perception, as the valve users on AoS are mainly regular contributors and often somewhat, erm, 'more vocal' than their, more numerous, SS counterparts :eyebrows:

We don't intentionally promote the use of valves - what we do promote is what we consider is the best in its field, usually on the basis of SPPV, and that could be valves or SS, depending on the equipment being discussed. And of course on AoS, everyone's opinion is always treated with equal respect.

Anyway, if there's anything specific you'd like to know about moving from Naim gear to valves, shoot away! :cool:

Marco.

MartinT
26-01-2011, 13:48
I have noticed that AoS is very much into Valves so much so I feel uncomfortable being here as a solid state user

Please don't be, Ron. There are plenty of us solid state users here on AoS, and we don't do the silly ss/valve arguments. Rather, there is a lot of mutual respect for both technologies.

Trickie_Dickie
26-01-2011, 13:49
Ron, let me put my pennyworth in.
I built my first valve amp SE, ecc83,el84,ez80 in 1958. Had it about 10 years till the mains transformer cooked. Have only owned solid state amps since. Built my first RCA transistor amps 70 watt rms 8 ohms early 70s. Still have them and they sound great to me. The rest have been mostly Technics stuff. Now, I'm looking at going back to basics. I still have my limited vinyl LPs & 45s collection plus a load of CDs. Personally, I can't tell the difference between Valves & SS until they are driven to overload. The distortion is so different.
I have two Technics SS amps in need of repair (blown outputs). Thanks son.
With me, its looks, just like women. Its nice to have something to depend upon for many years of service but a trophy is nice, too. :cool:

Reid Malenfant
26-01-2011, 14:14
I have noticed that AoS is very much into Valves so much so I feel uncomfortable being here as a solid state user. I know that Martin T uses solid state amps so I don't feel all alone on this particular subject.
Wave that solid state flag :exactly: Not a valve in sight here either ;)

It's simply a matter of perception, as the valve users on AoS are mainly regular contributors and often somewhat, erm, 'more vocal' than their, more numerous, SS counterparts :eyebrows:
Speak up boys, nows your chance :eyebrows:

Please don't be, Ron. There are plenty of us solid state users here on AoS, and we don't do the silly ss/valve arguments. Rather, there is a lot of mutual respect for both technologies.
I agree with the above :)

3570

:stalks: Ah, thing of beauty :eyebrows:

DSJR
26-01-2011, 14:14
The only valves I've ever had/used are in a buffer stage (MF) and in my headphone amp (MF) but I guess they can't be classified as totally valves? What this is leading to is if a music enthusiast has used solid state all of his listening life, in my case earlier Naims (okay, I can feel it comin' at me :lol:), how can they be weaned off 'em and towards using valves without too much of a culture shock and a deviation to what he is enjoying at the moment ? :scratch: I have noticed that AoS is very much into Valves so much so I feel uncomfortable being here as a solid state user. I know that Martin T uses solid state amps so I don't feel all alone on this particular subject.
That copper amp that Marco has looks absolutely stunning and is a work of art in its own right, obviously it must sound extremely good too but it must come at a high price given the bespoke nature of manufacture?

Where would you valve/tube/ thermionics followers make a start from if you were sitting in my listening chair? I must say I have heard some good valve sounds at the various hi fi shows I've been to but nothing that would make me junk what I have carefully put together over the years but I am open to an education. I don't subscribe to SS/transitors being Satan's work as Noel Keywood leads me to conclude :rolleyes:

I need a convincing education into the world of valves, erm toobs, please;)

Ron

Hi Ron, you need to visit Rock-Grotto for some excellent MF X series updates.
Hamish did his up too -

http://www.rock-grotto.co.uk/x-10dupgrade.html

http://www.rock-grotto.co.uk/x-ccessories.html

The mods I did to the X10-D were nothing short of sensational for a few tens of pounds and the excessive warmth/bloat has gone, together with the slight veiling the original had. All for around £65 including new valves. I also made up the simple 12V AC transformer power supply on the site and this is better than the heavier duty supply MF made at the time -

http://www.rock-grotto.co.uk/easyxpsu.htm

MartinT
26-01-2011, 14:19
Ah, thing of beauty :eyebrows:

You don't need central heating with one of those ;)

JazzBones
26-01-2011, 14:58
G'day Fellas, just back from lunch, Scotch egg etc (Do the chooks in Scotland really lay eggs like these :scratch: :)) Glad at the response I had and the reassurance... maybe the grey day was getting me down, eh? Anyway, I haven't shelved the idea of having a valve pre-amp (Croft maybe) with my Naim amps as mentioned elsewhere, its just that I have never had experience of owning or temporarily using valves at home, if I did it would be a combination of both or knock back on the box count and go for an intergrated (valve or SS, or hybrid) but this is all in dream time at the moment. By the way I did see a dirty big bugger of an intergrated MacIntosh amp complete with killer twin VDUs which look as if house foundations would need to be looked at :rolleyes:

Saw that video of the French bod making valves, even my wife watched with me, and all I can say, paraphrasing a TV prog, is 'France has got talent', can you imagine the fun that guy must have in experimenting with different types of valves. From the work involved I now see why replacement valves can cost big bucks.

The learning curve never ends and the education comes from within AoS I suspect :)

Ron

JazzBones
26-01-2011, 15:21
Hi Ron,

Are you genuinely thinking of going the valve route, or are you merely just curious about what 'toobs' might have to offer?

As a former 'Naimee' of many years, I came to valves from using a NAC52 and a pair of 'olive series' 135s, so I know just what the journey entails in terms of the sonic advantages and pitfalls...

Marco.

A combination of both Marco. I am given to understand that the affordable Naim pre-amps somewhat let the team down??? When I Avondaled my NAC72 I noticed the improvement after a few hours of use but then the burning question in mind is, 'could a valve pre go one better'?

Like life, you can keep on talking about it but there comes a time when butt removal from the sofa is required and a bit of seeking out the truth!

One thing thats blatently obvious is that Valve heads have a helluva lot more fun, like tinkering with classic cars, than the tranny guys seem to, I mean lay a big valve alongside a transistor and it does make the latter look like a cattle tick :lol:

Onwards and upwards :)

Ron

Marco
26-01-2011, 16:00
Hi Mark,


http://img811.imageshack.us/img811/5904/ksa20250.jpg (http://img811.imageshack.us/i/ksa20250.jpg/)


:stalks: Ah, thing of beauty :eyebrows:


Lol - I guess that beauty is definitely in the eye of the beholder! It may be a superb sounding amp, but it's as PUG UGLY as sin!! :lol: Way too brutal and utilitarian looking, and with zero finesse......

If we're talking beautiful looking SS gear, then short of something sexy and vintage from the 70s, with huge f*ck off fluorescent meters, it has to be the creme de la creme from Accuphase:


http://img253.imageshack.us/img253/603/m6000.jpg (http://img253.imageshack.us/i/m6000.jpg/)


Or Luxman:


http://img10.imageshack.us/img10/5895/m800a.jpg (http://img10.imageshack.us/i/m800a.jpg/)


The pics don't do these genuine beauties justice.

Those are about the only sort of things I'd consider giving up my copper amp for! ;)

Class A rules!! :fingers:

Marco.

Reid Malenfant
26-01-2011, 16:38
Aha, Marco took the bait 3574 :D

Yes i guess some would find it a tad overbearing, personally i like things when form follows function to an extent :) The other kit you pictured is rather nice as well ;)


Class A rules!! :fingers:

Marco.
I couldn't agree more, whether it be tubes or transistors :cool:

MartinT
26-01-2011, 17:39
To me, Accuphase has incredible cachet. That amp looks superb even though I don't usually like meters.

Welder
26-01-2011, 17:48
Oh dear, Iím way out of file here :eyebrows:

This is going to sound really really strange, but I listen to my kit, not sit there looking at it.
Oh never mind...........:doh:

Plenty of solid state enthusiasts here Ron :)
ď(Do the chooks in Scotland really lay eggs like these )Ē
makes you wonder doesnít it :eek:

DSJR
26-01-2011, 18:00
Class A rules!! :fingers:

Marco.

BOLLIX Marco!!!!! :D

With decent valves or modern transistors (available here long before they found their way to the US I understand), class B is fine, far more efficient and doesn't suffer the crossover distortions of old. IMO, component choice and layout is by far the most important thing.

Maybe Mr TD can post a comment or two to put me/us straight ;)

Marco
26-01-2011, 22:34
Well, Dave, all the (top-notch) Class A amps I've heard (valve and SS) have comprehensively outperformed their Class B counterparts, so maybe it was just a coincidence? ;)

Mark also appears to agree!

I know Anthony has some views on this, and can explain why (all things being equal elsewhere) Class A is better, so I will ask him to comment :cool:

Marco.

DSJR
26-01-2011, 22:39
Don't worry, I'll just go back to my Sonotone 20T and ancient ep's :D

Seriously though, I don't think all valve amps are class A are they? I'm sure the Quad II's aren't :scratch:

Marco
26-01-2011, 22:49
No I don't think they are, mate.

There are sound technical reasons, though, why Class A, done well, is the way to go, if you're after maximum sonic performance, which I'm sure Anthony or Mark (amongst others) could explain, although true Class A designs are very wasteful in terms of energy use!

I think it's something about always having 'power in reserve', without having to 'hunt' for it, to reproduce transients in music correctly.

There certainly has to be a reason why my 40W Class A valve amp (30W until recently) has far greater headroom and sounds subjectively much louder and more powerful than my old ECS 200W (Class B) monoblocks, when both were used with my Spendor SP100s, before the Lockwoods came into the equation....

Marco.

Reid Malenfant
26-01-2011, 22:51
Class A is inherently vastly superior to any other form of audio amplifier fullstop. They may not be as efficient but the fact that output transistors never turn off means crossover distortion is out of the window ;) All transistors suffer from beta variation in current gain, again this problem is out of the window with a class A power amp. Because all the current that the load ever needs is already being dissipated by the output stage the transistors never need to turn on harder & only need to swing a voltage. As they are already turned fully on this isn't a problem & happens much faster than a class B amp..

Class A is vastly superior to any class B amp as long as the components are the same fullstop. Faster, increased damping factor & an extended frequency response... A class A output stage can be run open loop with no negative feedback & still sound bloody amazing, show me a class B amp or any other that can do that :eyebrows:

Class A rules :fingers:

Marco
26-01-2011, 23:20
I think that sums it up nicely.... Honestly, though, the only way I'd ever return to solid-state amps would be to use some huge mutha of a Class A amp (such as I showed earlier), as that's likely what it would take to get near to replicating what the Copper amp does! :)

Marco.

Reid Malenfant
26-01-2011, 23:33
It's the same with tubes (or valves if being anal :eyebrows:), as long as the power is already there then nothing needs to turn on any harder so response is as good as damn it instantaneous. If it's already there then there is no time needed to turn things on harder to spit it out to the speaker :eyebrows:

Apologies as i'm not a tube convert - yet ;) The same applies though at the end of the day...

Marco
26-01-2011, 23:35
That's what I was going to say, too, and what I think Anthony will when he replies :)

I think you and I are after similar things, dude, although we've just skinned the cat a different way! ;)

Marco.

MartinT
27-01-2011, 09:42
Class A is inherently vastly superior to any other form of audio amplifier fullstop

I feel I need to redress the balance here otherwise we risk everyone thinking that class A is always best. There are many fine examples of class AB, sliding bias and even class D amplifiers that sound extremely good. There are many topologies that overcome crossover distortion to vanishingly small degrees and don't use heavy negative feedback. Class A certainly doesn't have it all its own way.

I particularly like well thought through MOSFET and JFET implementations, such as my own Chord. Some others, such as the Ayre MX-R zero-feedback balanced design and the new Mark Levinson No.53 switching amp, take different paths again and have awesome reputations.

So don't be too quick to stereotype :)

anthonyTD
27-01-2011, 10:53
It's the same with tubes (or valves if being anal :eyebrows:),
as long as the power is already there then nothing needs to turn on any harder so response is as good as damn it instantaneous. If it's already there then there is no time needed to turn things on harder to spit it out to the speaker :eyebrows:

Apologies as i'm not a tube convert - yet ;) The same applies though at the end of the day...

hi all,
what Mark has said above pretty much sums things up in a simplified way, however, class AB,and B amps [valve or solid state] can be made to work very well, its all down to power supplies and the type of circuitry and devices used.
i am not as some may think anti solid state, infact the best preamps i have built to date are mosfet types, however when it comes to power amps my prefrence is Valve, Class A.
Anthony,TD...

Gerry
27-01-2011, 19:58
I feel I need to redress the balance here otherwise we risk everyone thinking that class A is always best. There are many fine examples of class AB, sliding bias and even class D amplifiers that sound extremely good. There are many topologies that overcome crossover distortion to vanishingly small degrees and don't use heavy negative feedback. Class A certainly doesn't have it all its own way.

I particularly like well thought through MOSFET and JFET implementations, such as my own Chord. Some others, such as the Ayre MX-R zero-feedback balanced design and the new Mark Levinson No.53 switching amp, take different paths again and have awesome reputations.

So don't be too quick to stereotype :)

Agreed Martin.
A fair number of amps advertised as class A are not. (even valve/tube ones) They maybe class A up to say 10;20;30 watts then they switch to B, but the manufacturers insist on claiming class A. There was one not long ago in a HFW review. I have a pair of supposed class a 220watt mono blocks....they ain't or if the are they are, they most efficient ever made....not enough heat!

Reid Malenfant
27-01-2011, 20:18
I feel I need to redress the balance here otherwise we risk everyone thinking that class A is always best. There are many fine examples of class AB, sliding bias and even class D amplifiers that sound extremely good. There are many topologies that overcome crossover distortion to vanishingly small degrees and don't use heavy negative feedback. Class A certainly doesn't have it all its own way.

I particularly like well thought through MOSFET and JFET implementations, such as my own Chord. Some others, such as the Ayre MX-R zero-feedback balanced design and the new Mark Levinson No.53 switching amp, take different paths again and have awesome reputations.

So don't be too quick to stereotype :)
Ok, ok, you got me :eyebrows: I think you forgot to mention Halcro which like your Chord also uses an SMPS & has vanishingly low distortion (possibly the lowest ever measured), but that isn't the full story now is it...

Maybe i should have said that class A should win hands down for circuit simplicity & low overall feedback, though the multiple output transistors needed to cope with dissipating a lot of power kind of messes up the simple bit..

However, given precisely the same circuit increasing the quiescent current into full class A should result in lower distortion than any AB or B amplifier as long as the thing is properly designed (PSU included).

Obviously you can't do the same with a class D or T amplifier as these use PWM to regenerate a waveform after passing through a filter & while i'm sure there are some superb cases of these amps out there i'd feel more at home with one powering a sub (which is actually the case as it happens :eyebrows:).

By the way, i'm happily listening to a couple of AB amplifiers right now. One manages 28W (8Ohm) class A & the other about a Watt or so. Having built my own amps in the past though i know what i prefer myself :)

MartinT
27-01-2011, 21:16
I think you forgot to mention Halcro which like your Chord also uses an SMPS & has vanishingly low distortion (possibly the lowest ever measured)

That's the other one I had in the back of my mind! Personally, I'd have a pair of Ayre MX-R monoblocks given free choice of anything out there.

Welder
27-01-2011, 21:48
http://nadelectronics.com/products/masters-series/M2-Direct-Digital-Amplifier

I think we will all be revising our viewpoint on amplification in the next few years ;)

Seriously chaps, if you could all step out of the box for a couple of hours and take time out to just go and listen to one with an open mind.
I’ve heard one now and will be hearing another for a more relaxed listening session next month I hope.
It’s all over for the Class A v Class this, that, or the other, valves or solid state. This is just better.

Marco
27-01-2011, 22:40
Lol – John. Speak for yourself! "Better" in what way exactly – the best audio performance possible (which is all I'm interested in), compared to my copper amp, or Martin's Chord amps? I doubt it! ;)

Nah, as long as I can find NOS GEC valves to use, I'll be sticking to glorious glowing bottles, thank ee very much :cool:

Oh and just a note on "vanishingly low distortion"... Often, in my experience, the amps which exhibit such 'enviable' statistics also tend to rob the sound of 'life', and consequently reproduce "vanishingly low" levels of music!!

Marco.

Reid Malenfant
27-01-2011, 22:45
Oh and just a note on "vanishingly low distortion"... Often, in my experience, the amps which exhibit such 'enviable' statistics also tend to rob the sound of 'life', and consequently reproduce "vanishingly low" levels of music!!
Which is precisely why i like low feedback (or zero feedback) class A power amplifiers.

Welder
27-01-2011, 22:53
There you go, see what I mean; youíve made your minds up without even hearing them ;)
I canít say Iíve heard the best of any equipment, let alone owned it, but Iíve heard a lot of kit in my 35 odd years of being interested in audio and these are stunning.
You may not like them, they may not sound musical to you if youíre used to a particular sound. You definetly wont like the look of them.
However, as serious audio enthusiasts you owe it to yourselves to give them a listen.
After all, you guys have the funds to buy one and if later you cant get on with them Iíll happily take it off your hands on the strap ;)

Alex_UK
27-01-2011, 22:53
I think the "open mind" phrase in John's post may have passed you both by - don't knock it, until you've tried it, I reckon fellas... ;) I think we're all regularly telling each other to trust our ears, aren't we? And that statistics and measurements are meaningless - its what we hear that counts...? Not taking either side here, but genuine innovations are at least still possible, no matter how good the tried and tested technology is.

Welder
27-01-2011, 23:16
I mean what is it with you guys :lol:
Donít judge my aural discernment and experience of HI Fi by the system I have; thatís got more to do with my wallet and real life circumstances :rolleyes:
If someone who obviously has an interest in a subject tells me something is worth looking into, I donít look at what they've got and decide on my course of action by that, and dismiss their recommendation.
So, Iím telling you; theyíre worth listening to and even if you go along with all your prejudices and preconceptions you will still be impressed.
If you prefer the sound of your valves and class A thatís fine, but to dismiss these out of hand is downright foolish if you really are interested in audio reproduction :)

Marco
27-01-2011, 23:30
Lol!! I do not dismiss anything until I've heard it - I never have, and never will... :)

Therefore, for me, no conclusive opinions have been reached!

All I said was that I doubt the NAD would be my thing, based on what I've heard before from digital amplifiers.

However, if I get the opportunity to listen to one, and it blew me away, I'd be the first to say so here, so there! :ner:

Marco.

Alex_UK
27-01-2011, 23:43
Lol!! I do not dismiss anything until I've heard it - I never have, and never will... :)

Therefore, for me, no conclusive opinions have been reached!

All I said was that I doubt the NAD would be my thing, based on what I've heard before from digital amplifiers.

However, if I get the opportunity to listen to one, and it blew me away, I'd be the first to say so here, so there! :ner:

Marco.

That's all right then! (Doesn't look as sexy as your copper amp though!)

Marco
27-01-2011, 23:48
Which is precisely why i like low feedback (or zero feedback) class A power amplifiers.

And me, dude! :)

Marco.

Reid Malenfant
28-01-2011, 11:03
:lolsign: I'm not prejudiced against anything that i can think of, i was just stating a preference ;) You know the one, eight of of ten owners said their prats prefered it :eyebrows:

synsei
28-01-2011, 16:33
It occurs to me that I know very little about my DH220 other than the published stats I've found up to now. What they don't tell me is whether it's a Class A, A/B or B. Can someone enlighten me? It sure gets hot enough to be a Class A :lol:

lurcher
28-01-2011, 17:17
It occurs to me that I know very little about my DH220 other than the published stats I've found up to now. What they don't tell me is whether it's a Class A, A/B or B. Can someone enlighten me? It sure gets hot enough to be a Class A :lol:

I would guestimate from the power consumption in this link

www.hafler.com/techsupport/pdf/DH-220_amp_man.pdf

Thats its A for the first 15W the B after that. So A/B

Reid Malenfant
28-01-2011, 17:36
Odd, i made it 1.2W RMS class A into 8 ohms with a bias of 0.275A on the output stage :scratch:

0.275 x 2 gives the peak current in class A before the mosfets on one half cut off or 0.55A peak. 0.55 x 8 ohms is 4.4V peak, RMS voltage is peak/1.414 = 3.111V RMS, square that & divide by the speaker resistance = 1.2W