Rotel Amp mute relay/cap?

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I have a Rotel 810a which suffers from the big pop when switching on and gradually fades out when switching off. So I've had it apart looking to see if there was a mute-start relay I could replace - but can't see one. I found a thread on another forum for a similar problem saying to replace the switch bypass cap - and this appears to have a 4.7nF cap across the on-off switch - a Y-rated capacitor.

Can I replace this with a any cap rated above 240v to test or am I asking for trouble doing this?

This is the type
http://www.mikrocontroller.net/attachment/11687/Bauteil.jpg
 
I didn't like the turn-on or turn-off of my Rotel RB-850, so:

I added a Potter and Brumfield delay on relay to switch the outputs
on 10 seconds after power up and they close imediately on power
down. I used on leg of the power supply to run a bridge rectifier
and 12V regulator. . .works great and simple install.

Not to say the cap isn't the solution, but this also eliminates the
output continuing with decay at power down.
 
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Joined 2006
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I finally got round to replacing the switch bypass cap - and it was the same with the new cap, so it must be elsewhere.

gni - are you saying the thump-on and fade out was standard with yours?

I shall start looking at the time-delay relay idea.
 
There was always a slight thump at turnon. . .there is nothing in the
circuit to prevent it. . .the amp is on or it is off. . .when you
turn the amp off. . .and let your source continue to play. . .sound
will be amplified until the caps run down. . .that is why I used the
delay relay on the outputs.
 
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