New Electrocompaniet AW120 clone

[hollow_man]

This is what I have come up with. Design is largely based on AW120, except original protection circuitry, voltage amp power supply
and a small twist on input stage biasing.

Would anyone care to comment on the pcb design, as it is getting toward completion? Left and right channel signal paths are mirrored except around the output transistors, where I have tried to keep respective trace lengths equal.
What would you do in a different way? Any other comments/ideas are welcomed.

Cheers.

[hollow_man]

That' d be the schematic.

[garga]

Welcome
Very nice project!
I would like to ask for help
Electrocompaniet AW-180 schematics I need
Thanks for your help
my email address
gargafater@freemail.hu

[powjemini]

Originally Posted by hollow_man

That' d be the schematic.

Hello hollow_man
I saw the schematic of the amplifier and i was wondering how the feedback network from the "OutR" works. It seems it goes to a 8K2 resistor, but i would expect a second resistor from there connecting to ground. As it is now it seems like being an amplifier with 0 dB gain.

[hollow_man]

Hi Powjemini,

this design is along the typical EC lines, whereby the first section of the amp operates open loop as a transimpedance amplifier with a very high output impedance. However, it 'sees' the 8K2 output section feedback resistor as its load, which establishes a given voltage gain. The output section indeed operates with 100% negative feedback, so its voltage gain is unity.
Hence you could say that the voltage gain is determined solely by the 8K2 feeback resistor (within limits).

Regards,
hollow

[hollow_man]

As you may know, down here in Greece we have as of late been shattered with deep salary cuts, very steep taxation, job losses etc, so sadly I cannot proceed to the elusive construction phase...