AC30SS hi-res schematics

[Robert M. Martinelli]

Hi all,

This came out from a member's private request, but, knowing that there are no good scans of this on the internet ( all the ones I've seen really do suck ) I thought it could be good to post it here for all to see.

Last Tuesday, after rehearsing with the band, I took my old AC30SS home, removed the back plate from the chassis, and scanned the schematic diagram at a very high resolution ( the original .bmp file was over 50 Mb ! ).

The amp is in near-mint conditions, so no rust or stains, and the ink's still all there, making the scan far more readable than the ones around.

I saved it in .jpg format and zipped it to cope with the attachments' size limitations, hoping that, sooner or later, it will be useful to someone.

Best regards

Bob

[Twist]

Thanks, I'll add this to my files.

[Enzo]

Cool, me too.

[Yves Haesler]

Thanks for zip.I bought recently an AC30ss.

[sapoluengo]

You could give me the values of the components marked

thanks!!!

[Robert M. Martinelli]

Sorry for the late reply, but I had to open the amp to answer your question.

From left to right:

Thermistor, NTC, 55 Ohm at 25°C (77 °F).

Resistor, 22 Ohm

Resistor, 2,7 KOhm

Hope this helps

Best regards

Bob

Note - The NTC is part of the bias network, its purpose it's to keep the bias stable vs. temperature, so it lies right on the power stage's heatsink, stuck to it by means of some thermal compound.

[Dave Curtis, dB AudioTech]

I added the values...