20 Most Recent Peavey Electronics Peavey Tour Tnt 115 Combo Bass Amplifier Amp - New! - Page 6 Questions & Answers

According to Peavey it was made in 1978, in the USA

Peavey can supply most all the parts for their gear and sells directly to end users. However, they now charge shipping on parts (they didn't used to) so it's best to grab more than just a single pot when you order. Corners, feet, handles, etc

I get good 8" speakers from- Richter 8 8

https://www.allaboutcircuits.com/textbook/direct-current/chpt-14/electromagnetic-induction/ The AC power changes the magnetic field and may be being picked up in your amplified leads . Or the DC voltage in your amps power supply is not filtering the power after it rectifies the AC power .A really big capacitor across the dc voltage output from the rectifier should filter any AC out. https://www.allaboutcircuits.com/textbook/experiments/chpt-5/rectifier-filter-circuit/

Disconnect the leads from the 12". Put a voltmeter across the speaker terminals and check for continuity. If it reads open, the speaker is dead.

Why not un-complicate the circuits by eliminating the soundboard first?

FB2 SAB is a 'cement' type resistor.The value is 560 ohms.The power rating is 3 watts.

but you would have to go to Peavey direct for service info.

Download the schematics.... https://elektrotanya.com/peavey_cs800s.pdf/download.html

https://www.google.co.za/url?sa=t&source=web&rct=j&url=https://www.manualslib.com/manual/121231/Peavey-Programax-10.html&ved=0ahUKEwjYt_2T0ePSAhWJKcAKHbbBBe0QFggaMAE&usg=AFQjCNEj73j40pNjQwVnQCnNGH8EZjt-3g&sig2=Fi05Gh3RwaYJEePyOcMDeQ

You need to contact Peavey directly for the best solution. Here's their links- peavey com

What is your question about the mixer?