Simple Symetrical Amplifier

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LC, that line is so true.

Hi Andrew, I have a plan for solving the problem you mentioned. I am on it.

You forgot to say cunning plan
 

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"it feels like the speaker is way bigger, all over the wall.

I experienced this 10 years ago. I couldn't forget the amp and couldn't understand why my (supposed to be better) later amps couldn't do the same .

Only not long time ago I know that it was a CFB amp. Only opamp was used for the input. The opamp was better than 5534, but the lousy sound of opamp was there (Sorry to those who cannot hear the sound of opamp :D)
 
IOnly opamp was used for the input. The opamp was better than 5534, but the lousy sound of opamp was there (Sorry to those who cannot hear the sound of opamp :D)
It was the Mark Alexander's one ?
About Op amps sound, just try some CFB ones :)
I'm not able to feel any change between 4 of them in serial with several configuration (inverting/non inverting, 10X gain or 1) and a strait wire in instant comparison.

It is out of topic, but i had all my life a problem with the analog mixing desks: The mixing bus is the - input of an opamp. So, more you plug tracks " in the air", more the gain of the amp increase to keep each track at the same level, and more the sound is ' lousy'... until i changed-them for C.F.B. ones...
 
It was the Mark Alexander's one ?
About Op amps sound, just try some CFB ones :)
I'm not able to feel any change between 4 of them in serial with several configuration (inverting/non inverting, 10X gain or 1) and a strait wire in instant comparison.

It is out of topic, but i had all my life a problem with the analog mixing desks: The mixing bus is the - input of an opamp. So, more you plug tracks " in the air", more the gain of the amp increase to keep each track at the same level, and more the sound is ' lousy'... until i changed-them for C.F.B. ones...

Yeah I know that for everyone else, the amp was about CFB, but for me it was about IGBT :clown: I knew anything about CFB amp was only after the SSA (honestly, I followed the thread because of the IGBT thing). When I looked back, I realized that many of the good circuits that I prefer were CFB. I also liked to choose a small FB resistance, VFB or CFB.

Stochino amp for me was about high slew rate amp. Then I started to look at slew rate parameter in opamps. Coincidentally most CFB amps also have high slew rate.

And the AD opamps are I think the best I have heard. But I couldn't accept any preamp. Preferred discrete. But lately I can accept tube preamp (as part of the DAC I/V) after extra work had been done with the power supply.
 
I experienced this 10 years ago. I couldn't forget the amp and couldn't understand why my (supposed to be better) later amps couldn't do the same .

Only not long time ago I know that it was a CFB amp. Only opamp was used for the input. The opamp was better than 5534, but the lousy sound of opamp was there (Sorry to those who cannot hear the sound of opamp :D)

I am sory for those who (think they) can.
Myths in Audio
 
I am sory for those who (think they) can.
Myths in Audio
Very refreshing. Despite we can reasonably argue with technical arguments and experience against a quarter of the sweeping assertions of the author.
That kind of popularization helps newbies to be aware of snake oil vendors.
But thinks are not so simple.

There is no reason to believe more this kind of articles than the assertions of the snake oil vendors, apart their motivations.

The only scientific way is to learn the theory, experience-it in real life, and try to correlate thinks (What you listen and what you measure).

There is no problem with OP amps. And i don't prefer discreet against them. More than that, their little surface offer a lot of technical advantages. There is a difference in schematics, components of them and the way they sound (and measure) in different implementations.
As an example, my preamp is made from Op amps, but the last stage is boosted with discrete transistors, as i was not able to find one fast enough with enough current.

Yes, most of us can feel the sonic difference between a TL072 and 2N5532 in a given configuration: It is obvious. Despite they all reproduce music and measure in a decent way.
As all of us witch had build some SSA can feel the difference between it and our previous amp. (No one seems disappointed :).
 
As all of us witch had build some SSA can feel the difference between it and our previous amp. (No one seems disappointed :).

Of course, I call SSA the Holy Grail.

As it has,

1. Huge bandwidth, easily scalable.

2. Huge slew rate, easily scalable.

3. Huge power, easily scalable.

4. Huge portability.

5. Huge usable gain.

6. Common components, can be substituted with minimal change in behavior.

7. Easy setup.

8. Excellent thermal stability.

9. Excellent bias stability.

10. Excellent PSRR.

11. A balanced input version, for the interested.

12. Standard three stage gain structure, easily scalable.

13. Excellent phase up to 100KHz, scalable.

14. No need for O'scopes for a simple and working setup, only multimeters.

15. Very simple design, can be scaled to very complex.

16. Support and recommendation from renowned experts in diyAudio :).

17. Many ready-to-etch PCB designs, from simple-low-power to complex-monstrous.

18. A Class-A sister, TSSA, for the interested.

19. A bright future, as CSA is almost done.

20. 24/7 unlimited free online support. :eek:


_____________________________________:cool:
 
I am sory for those who (think they) can.
Myths in Audio

Hi dadod, I think you're underestimating us, just a little bit. Yes? We are not fools here dealing with myths, trying to believe nonsenses, as Esperado nicely put snake oil and stuff.
We know charachteristics of a real electronic parts, their performances, limitations and some proved topologies that can play music, to give listening pleasure to a person who had experiences with other good amps too.
Me personally like the amps enabling music to come out of speaker boxes, play with realistic attributes as possible, trying to fool my senses that there's real stuff going on in the room. :yes:
 
Hi all.
I added some useful SSA links to my signature place. Hope this will be helpful for the new readers of this thread.
Please direct me to other important links that I missed and I'll add them.

:2c:

Hi LC. Thanks for the kind words. I just said what I felt.

I Will be very happy if what you said later happens.
 
Hi dadod, I think you're underestimating us, just a little bit. Yes? We are not fools here dealing with myths, trying to believe nonsenses, as Esperado nicely put snake oil and stuff.
We know charachteristics of a real electronic parts, their performances, limitations and some proved topologies that can play music, to give listening pleasure to a person who had experiences with other good amps too.
Me personally like the amps enabling music to come out of speaker boxes, play with realistic attributes as possible, trying to fool my senses that there's real stuff going on in the room. :yes:

Do I?
(Sorry to those who cannot hear the sound of opamp :D)
 
So what's stopping you from making SSA BIGBT HP. This one I built and have plenty of info to support you if decided to start, just say a word ... ;)

Says who I haven't built it. But I didn't build the original. I always start with simulating the originals then build my own versions based on available parts. In some cases, I have to scale down the performance, in some others, I have to scale up the performance.

I don't know what is wrong with cascaded VAS. They are wonderful in simulation (simulating the wrong things?) but musically they don't perform as good as their numbers. I have built many amps with cascaded VAS, including the Accuphase, but they are not my favorite.

BIGBT output stage. They are good. Just good. No more than good :D I'm skeptical you know, about this kind of output stage. They all have strong character.

Lately I'm working with SSA-BJT Class-A. Many things are new, visually and non-visually. Visually, the output topology has not been seen before (as far as I know). Non-visually, I tailored the two impedances at input and FB to get zero volt at output (no trimmers, all symmetrical, below 10mV is easy).

I haven't done much with SSA_LATFET (I don't want to loose more LATFET). I only do simulations to find out the best possible topology. I found 2. The best one is used by Nico/Shaan, and the other one I couldn't make it stable (Drain output LATFET driven by the collector of an EF BJT). So I used the topology used by Nico/Shaan, except that I don't use the input cascode. Simulated performance is much better, mostly because of optimized operating points (higher voltage about 41V) and regulated power supply. Like Shaan, I don't like complex circuit at the input, so no complex ccs so far.
 
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