tube-like SS power amp

[Bigun]

Build such an amplifier, and do the AB testing. /B]

I'm trying ! - but it's frustratingly slow. Parts on back order, no acetone to clean the pcb off with, wife wants the deck finished first...

But I'll build the TGM 1.0 with the 'fudged front end' and I'll compare it with my Bryston ultra-low distortion box.

 

[Bigun]

This reminds me of my other hobby. Photography. You'd be surprised how many people think they want a lens and camera that captures what they see. But eventually they discover that they don't see what's really there. Their eyes & brain see what they want to see. So in the end they want different colours than appeared in nature, they want deeper blues, richer greens. They want lenses that show nice blurred out of focus highlights. I don't see why audio is any different. There will be people who prize accuracy (professional users for sure) and those who don't but will pay a small fortune for what they like

 

[nigelwright7557]

This reminds me of my other hobby. Photography. You'd be surprised how many people think they want a lens and camera that captures what they see. But eventually they discover that they don't see what's really there. Their eyes & brain see what they want to see. So in the end they want different colours than appeared in nature, they want deeper blues, richer greens. They want lenses that show nice blurred out of focus highlights. I don't see why audio is any different. There will be people who prize accuracy (professional users for sure) and those who don't but will pay a small fortune for what they like

Its also very similar to electric guitar sounds.
Guitarists will pay hundreds of pounds for effects boxes to totally distort the sound.
I use a Zoom 707 effects box and it is amazing.

While purists look for amps with 0.0001 % distortion guitarists are possibly running upto 100% distortion !

Wah wah, flanger, phaser, echo etc etc all distort heavily but sound great.

 

[GK]

you can get just as much distortion from OVERbiasing as from UNDERbiasing the output devices, which is why it's best to set the bias with a distortion analyzer. same thing goes for tubes.

More bias is always better for tubes (within reason) and they do not suffer gm doubling distortion. Also, under biasing just about any output stage (valve or SS) if FAR more detrimental that over biasing it.

Tube power output stages and SS power output stages are apples and oranges. IMHO you cannot make a typical class B SS power amplifier sound like a typical (audibly distorting) valve amplifier just by compromising the stages preceding the power output stage – this only has potential to makes things worse.

Incidentally, here is a valve amp I’m currently getting ready (half the caps currently replaced). Push pull EL84 and gobs of global negative feedback. This one, believe it or not, “sounds” just like a well designed, low THD solid state amp.

Cheers,
Glen

 

[jcx]

The Carver-Stereophile Challenge is always good to toss in to these discussions - not that it appears anyone actually changes their beliefs on tubes vs solid state in the face of mere evidence

http://www.diyaudio.com/forums/showthread.php?postid=152392#post152392

 

[JLH69]

JLH describes his amp as comparable to a Williamson:-

www.tcaas.btinternet.co.uk/jlh1969.pdf

I've never heard a Williamson, so can't comment.

 

[destroyer X]

I have listened the Williamson...and really seems

alike..but this was made using memory..to be sure i have to play both amplifiers same time with same souce of music playing and switch speakers after adjust them to the same power.

Not easy to do now a days.

regards,

Carlos

 

[GK]

The Williamson is a low THD design that uses lots of negative feedback. Designs of its kind are shunned by many modern day tube devotees due the allegedly boring, solid-state-like sound.

It took some time for solid state designs to better its performance.

Open loop SET amps with >10% THD are all the rage in tube land.