SYMEF amplifier

[OnAudio]

Schematic link for V2024 updated. The SYMEF amplifier off the bat was a great amplifier, so even improving it becomes hard.

 

[OnAudio]

In the v2024 version on first post If using low ESR CAPS, polymer, tantalum etc slow start the regulator, many a regulator has been prematurely welcomed into silicon heaven while charging up a low ESR capacitor, unexpectedly cutting short an audiophiles taste of heaven

 

[evette]

do you have pcb,s forsymef type 4.

 

[OnAudio]

Hi Joe, PCBs are always available

 

[evette]

ok i,ll send my order in a few days

 

[evette]

ps. whats the cost per unit in red or black

 

[OnAudio]

Use the link in first post for PCBWAY it will depend on what options you choose

 

[evette]

i can,t find this at pcway

 

[meanman1964]

https://www.pcbway.com/project/shareproject/SYMEF_Audio_Power_Amplifier_8bb70aa8.html

 

[OnAudio]

Spoilt for choice! welcome the newest member of the symef line up, can you tell them apart in an AB test? Check first post.

 

[OnAudio]

Crossover distortion in EF3s is minimal while non existent in Quasi designs, but all types of output stages should work just fine if sufficiently biased

 

[OnAudio]

Have improved the Ensemble schematic in first post

 

[OnAudio]

The mounting dimensions and holes are backward compatible and both have 0.000X% THD

 

[OnAudio]

A good video on some pitfalls

 

[OnAudio]

SYMEF is pretty low noise with some calling it pitch black with no noise even with the ear against speaker. Is ensemble the lowest noise SYMEF?

 

[Alren]

Hello,

I discovered this post with interest but I must admit that I no longer understand anything.
Indeed, in the 61 pages of this post, there are many schematics and variants: generation 1, 2 and 3, version S, version P4.
You return to the PCBWay site and we discover two schematics still different from the first, associated with comments from generation 1.
Could you clarify all of this?
Thanks in advance.
Alain

 

[OnAudio]

Thanks @Alren , you can build the ensemble

 

[Alren]

@OnAudio

OK, thank you.

I'm going to go for the type S Ensemble set.

What changes would need to be made to have a balanced input ?

 

[OnAudio]

Cheers @Alren. You can use a preamp/opamp that does balanced to unbalanced. Unless your running long cables , unbalanced should work just fine. If your preamp outputs are only balanced , you can mod the receiving balanced connector so that the amp only uses the positive signal, you could also use an inverting opamp on the negative signal to sum to the positive signal to a summing opamp that feeds the amp.