Simple Symetrical Amplifier

[Nico Ras]

Carlos,

Won't it be great to have a simulator that can actually play music and produce numbers.

[Lazy Cat]

OoooK we will stick to the first one and see what will happen.

Sorry guys I guess I am just bored here ...

[Lazy Cat]

Originally Posted by destroyer X

now more second harmonics...the first layout was the best one in the simulator..of course real world can be different.

More second harmonics, isn't that even better?

So that immediately tell us something, it looks we should leave 1k bias trimmer parallel with 100uF elco in function to stabilize +/-0,6V bias voltage of the input pair.

I think real listening tests will tell more ...

[digits]

Originally Posted by destroyer X

‪EEVblog #29 - Audiophile Audiophoolery‬‏ - YouTube


Carlos

Ahaha I love this guy, his clips has been pretty usefull to me in the past, I seriously doubt he is an audiophile though, he strikes me as too no nonsense for the type.

[destroyer X]

Sound is another thing as you know... there are many guys that believes in numbers.... i do not believe...i use numbers to have a good communication with the ones like numbers..but i really trust in listening tests.

Well....i am really busy doing other amplifiers, i hope someone give a try on this one and say something about.

If simulators could play music...distorting when distorted...increasing second harmonics, or third, or fourth...producing something we can trust...for sure would be lovely....maybe the future will bring this for us...but even this way will never substitute human ears, human feeling while listening...there are much more than music in that stuff..there are feelings...the communication with our souls that some amplifier can make ...and others not...this is not measurable.

Guys alike Hugh Dean when around an amplifier seems a lot to me.... this is a good sign about this design...also you Nico is around...this is another good sign....if people alike you are here...the amplifier may be very good.... when we see smoke.... well....must have fire around...when we see good guys around some amplifier is because it may be good.... these signs i respect... follow the good guys and we will have something good to listen.

regards,

Carlos

[destroyer X]

and we sometimes do not match his ideas....sometimes he is right...about this video i can agreed with him in almost 99 percent.

He loves Multimeters...also he has a very demanding mind about electronics...i do like he become upset with our audiophile world that has some exotic ideas...i feel him funny...i do like him.

Sometimes he shakes me...sometimes he shocks me... i use to be watching his video from time to time....i have some troubles to understand when he is being ironic or talking serious.

this Greek audiophile club video makes me laugh sometimes...it is a good reference to us, to think about the stuff.... avoiding us to loose contact with the reality.

regards,

Carlos

[Nico Ras]

Lazy Cat, I should have mine done by tomorrow afternoon (my time) to give you my "subjective" review. What I would like if Alexmm is around is to add the power supply caps and rectifier on board thus making a nice amp with on-board power supply and it is only necessary to add a transformer.

Lazy Cat kindly draw Alex a schematic showing the non-electrolytic by-pass caps and maybe replacing the BFs with BCs. I would suggest four on-board 10A rectifier diodes and two 4700uF/63V caps.

[Lazy Cat]

Yes Nico, simple one PCB amplifier should also have all on board connections, that would make it even simpler, real beauty to DIY-ers.

So I prepared quite standard power supply sch to be located together with amp on the same PCB. Connector for the transformer secondary AC in should be Phoenix type with screw wire fixation. Diodes could be other type, but certainly ultra fast recovery type to minimize on/off transition high frequency polution to the rails. Filtration is calculated to approximate power consumption of this specific amp, but can be altered or change accordingly to the best functionality.

[Nico Ras]

After building a spider web mock-up, my first impressions were that it sounded very good, but after a while it fatigued me a little (listen on headphones HD800s, which is the easiest way to get irritable). Subjectively I would say that the odd order harmonics may be responsible as it sounds too crisp/detailed for my liking. Transients are excellent bass is very tight and probably due to the high bandwidth.

Lazy Cat, I made a few modifications to the circuit and I now appreciate your design much more. The mods evened out the harmonic artifact and the subjective sonic results are excellent (no measurements has been made this is subjective only)

I do not want to corrupt this thread with modifications as I have asked you not to and would like to ask if you would start a new thread calling for Simple Symmetrical Amplifier Updates, and I will post my stuff there.

Kind regards

Nico

[Stormrider]

Originally Posted by Lazy Cat

Yes Nico, simple one PCB amplifier should also have all on board connections, that would make it even simpler, real beauty to DIY-ers.

So I prepared quite standard power supply sch to be located together with amp on the same PCB. Connector for the transformer secondary AC in should be Phoenix type with screw wire fixation. Diodes could be other type, but certainly ultra fast recovery type to minimize on/off transition high frequency polution to the rails. Filtration is calculated to approximate power consumption of this specific amp, but can be altered or change accordingly to the best functionality.

Per popular wisdom, your grounding is wrong. The main filter cap gnd should not be connected through the star point. They should have their own connection straight across, preferably with solid copper or aluminum bar, and then the center point of that goes to the star. Minor difference in your drawing, but it can be make a big difference to how a PS is wired or laid out on a PCB.