Crown D75 snap, crackle, pops

[Michael F]

When adjusting the attenuators. It used to be much worse prior to Deox-ing them. There is a DC component present while crackling which is of too short duration to be accurately measured.
Can this be the effect of failing capacitors somewhere?
Thanks for looking

 

[rayma]

Would have to be the C101, unless the pot is just worn out.

 

[ubergeeknz]

You need to remove any unwanted breakfast cereal mascots. If you can do that I'm sure it will sound grrrrrreat again

[emoji1787]

 

[indianajo]

So the rails are +-30 vdc. Is that what you get on + & - terminals of C1, C2?
Warning to newbies, work only with one hand when checking with the power on. Use alligator clip to connect DVM negative to speaker return. >24 VDC across your heart can stop it. Wear no jewelry on hands or neck. 1 vdc @ 30 amps can burn your flesh to charcoal. Touch no metal with flesh until checked <1vdc and unit unplugged from AC.
Volume pots often wear out on old amps.
You can download service manual from eserviceinfo.com

 

[Michael F]

I just downloaded the service manual, C101 and C201 seem like a good place to start looking. I`ll report back with my findings.
Thanks to all who chimed in

 

[rayma]

I just downloaded the service manual, C101 and C201 seem like a good place to start looking.

Use bipolar types only. They're overdue for replacement anyway.

 

[Michael F]

What role does that cap play exactly?

 

[rayma]

What role does that cap play exactly?

Input blocking capacitor, just after the level control.