TSSA - The Simplest Symmetrical Amplifier

Well,

I'm not that worried about H2, 3 etc

It's extreme low H6 - H20 & other noise of all types that gives a very clean, transparent & detailed sound.

I look forward to see when you present them

mike

Hi Mike.

Here they are. This is real life measurements
 

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mmmm - those 10W figures are higher than I expected - almost in valve amp land.

But valve amps can sound very good - do you have any further comments to make to convey to us the sound of this amp. For instance compared to your other best designs.

Is it good for a simple amp or good by any standards ?

thx

mike
 
The amp sounds very very good.. clean crisp and very very detailed in a true musical way. Not much can compete with this. I have built now 3 different versions of the SSA. this one is the clearly the best. It may not have the best specs, but then what is specs...?? sine-wave deformation..??

The pure simplicity of this circuit really makes it shine, less grain, less sand... I LIKE..!!
 
thx Sonny,

Do you think it would work ok with + / - 25V supplies - biased to 1 amp / channel ?

That's how my DC fetzilla are powered - so good comparison - could use my choke regulated PSU's.

If I prefer my Fetzillas then I'll return the favour - if you like - once I make up some more - but I would strongly recommend using choke regulated supplies.

At present my Fetzillas are the most transparent, detailed & natural amps I have ever heard - and it's hard to imagine something better ;) - but I would be happy to be surprised.

mike
 
Can't tell you why, but the horse may lie somewhere in the execution or.... this number three version of the SSA I have is currently the best of my SSA's, but still it lacks a little compared to Sonnys, In all respects it's actually better, more power, deeper base, better grip same level of detail but sonny's amp plays the music in a better way. It simply makes more sense. Now I'm not a measurement guy or a guy with an utter love for my own creations, but I do have access to some very very good equipment, superb cables and also a good collection of reference equipment. Sonny brought his amp, and what we have got whipped. My third incarnation of the SSA is closer and in some respects better, quite sure it measures better, but it lacks some of this special magic that Sonny's amp has.... could be the Drain output, that holds the magic..?? Still some work to do for me...:)
 
Sony and Michael I clearly believe your's sound impressions, since I know what kind of amps and systems you both have experienced so far. If you both says it is OK, I know it is so. :up:

Me also know what SSA/TSSA amps are capable of and that is the major reason why still digging further on into this topology. As a result, as you all know up to now, CSA was started. Before opening CSA thread, here's front-end, populated with resistors and semiconductors just for a taste. :drink:

:cheers: Andrej
 

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I think that 0.1% low order distortion does not sound distorted for the ear. Of cause i would like to see better numbers but maybe conventional high feedback amps have other problems like energy storage ( settling time ) or there is interface distortion when the speakers are connected. I still listen to my TSSA version that is even simpler then sonnys and nobody is complaining. I use high sensitivity speakers though and under 80Hz my subs are active so the TSSA does not have to work that hard in the bass.
There has being discussion in other threads why some amps with high static distortion like tubes sound better to some people. Maybe a little bit of harmonic distortion is even good to make the music alive. There is a certain loos of harmonics on all recordings, may it be the truncated response of microphones or may it be strict bandwidth limiting in CDs. I know that arguing that way is waking in muddy waters but what the heck !
When it sounds good it is good.
 
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I Think Joachim is on the right track , i also believe that this is due to energy storage. We try to thermally compensate the front end. That is a weak point in a SSA front end but also in a diamond buffer.

The Working point is only changed by a small amount in the TSSA. Delta vbe/1k where the SSA have a delta vbe/100. The SSA has a change in the Working point of a 10 factor compared to the TSSA .

We Can compensate the change in Working point thermally, but it is fast enough? Even when the transistors are on the same die?
 
mmmm - those 10W figures are higher than I expected - almost in valve amp land.

I'm curious how it looks in simulation. Standard source follower versions do not have this character. Thanks to Sonny to make the CFP driven by BJT (so I can build it also).

but sonny's amp plays the music in a better way. It simply makes more sense.

some of this special magic that Sonny's amp has.... could be the Drain output, that holds the magic..??

Yeah, it could be both the Drain output and also harmonics that is caused by FET?

Drain output tend to sound relaxed and musical, but doesn't need to have high harmonics.

High harmonics tend to sound sweet in the mid-high, I guess it is caused by the "imbalance" between NJFET and PJFET so can be fixed/trimmed for those who prefer clean amp?
 
Hi LC, i just finish to populate my own Brother of quasi pcb : http://www.diyaudio.com/forums/solid-state/88258-brother-quasi-43.html#post3093264.

So I will have soon more time to go foward on my TSSA-BIGBT HP project. I mesure all BC on DMM as the KSA/KSC. Need to purchase TLP627 and some 1µ wima. I will probably direct go for separated first stage own power supply. LC have begun the step by step guide you talken from?

Marc
 
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After i have changed the drivers to bipolar, it sounds like the base has improved.

Also the dual mono setup is done.

I was listening to Ludovico Einaudi "The Tower". First i think, this cannot be right. It sounds distorted - Wrong... The attacks on the drums was extreme..

Melody Gardot - The hearts is black as night... Piano deep tones has more attack..

But i am not sure as, i am not as trained as you Michael.
 
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Interesting write up by the magazine, I see the designer is now using circuitry he rubished when he made the model one. I read the other day a interview with him by a hifi magazine some years back where he states that it took him 16 years to develop it and how bad some of the circuitry that has now gone in into this new model is and found it very amusing.

What he doesnt tell you is that all he did was to copy a old 1978 Revox design, take the feedback out from the output and present his new design. How he was allowed to patent his complete amp is another mystery as his input stage was used by Revox and public knowledge.
He did mention that he knew one of the designers from Revox pretty well, thats explains most of it. :rolleyes: :D

There are some really interesting characters involved in audio. :D