TSSA - The Simplest Symmetrical Amplifier

[Lazy Cat]

Originally Posted by Joachim Gerhard

I am at the Fast Audio boot. You can see an interesting preamp with phono stage i designed. It has tone controls and a tube output stage.

Very good, it interests me to see it, especially ideas behind.

I thought you're more in speakers R&D, AP background.

[Joachim Gerhard]

I design speakers too but that is not a big challange any more after more then 40 years. The only things that are left is radiation pattern and mechanics for me. I do more electronics now.
Yes that latfet drivers are pretty famous for good sound.
Anyway, if there is interest i can build a second amp with high current and no drivers.
This amp already feels like an old friend to me. I am totally convinced that using the output laterals as current fed back current sources is the way to go. High feedback emitter or source followers have problems to drive a complex load. See the measurements in the new Stereoplay.

[Lazy Cat]

Originally Posted by Joachim Gerhard

I design speakers too but that is not a big challange any more after more then 40 years.

One info interests me the most. What kind of speakers has the man now, with all that experiences and background of more than 4 decades. Please say something about your favourites, ie. you listen to nowadays.

Originally Posted by Joachim Gerhard

This amp already feels like an old friend to me. I am totally convinced that using the output laterals as current fed back current sources is the way to go. High feedback emitter or source followers have problems to drive a complex load. See the measurements in the new Stereoplay.

I'll find to see that, interesting, thanks.

[sonnya]

2SJ76 and complementary.

MOQ is 1600pcs each.

So there is enough for 800 stereo pairs

Delivery time : 20weeks

Price : ~1 - 1.5€/pcs

[Joachim Gerhard]

I use high sensitive speakers at home. One is the Suesskind Sommerwind. It has a 30cm Von Langa fieldcoil in a 140 liter double wall cabinet and a special high sensitivity Mundorf AMT over 1,4 kHz. The other speaker is a G-Pole with 2 Enviee drivers and an active bass. That is an M-frame coupled to the backwall with a granite plate. I recycle the back EMF so that the bass drivers have no excess movement. I am preparing a patent.
You can see some of my setups on my MPL thread.

[Joachim Gerhard]

Here you can buy smaller quantities but more expensive.
schulelektronik.de - elektronische Bauelemente - Transistoren - IC´s - STK - Kondensatoren - Widerstände

[Joachim Gerhard]

here is an example.
i also have sources in japan.

[Jay]

Originally Posted by Lazy Cat

Hi Gerhard 6800 uF feedback elcos

Back to back to make up 3400uF NP. We can connect the negatives together (BP) or to connect the positive together (NP) as in Gerhard's and the sound is different. I don't know which one should go into which situation. The last time I tried BP sounded better.

[Joachim Gerhard]

No, this is not bipolar but of cause a bipolar can be made that way. I connect minus to minus usually.
Cyryl Bateman found out that this gives less distortion but a "real" bipolar like Nichicon Muse ES has even lover distortion.

[Lazy Cat]

Hi guys

Gerhard and Sonnya (and others if any interested) please look at change in schematic. 2200 uF/10 V capacitor added to feedback bridge (from TSSA BIGBT HP and SSA experiences) for extra distortions reduction. This elco decouple middle bridge DC from any AC being present because of unsymmetry, secondly it will cause our amp to raise bias slowly from firing-up, some sort of soft starting. Since this is symmetrical design we don't want anything to spoil our little symmetrical toy.

BTW how's P2P work standing now Gerhard, do I have to wave the finish