Crimson Monobloc Question...

Hi,

My Crimson Electric 630 monoblocks have recently started to "thump" my speakers when the pre-amp (Cambridge A5) is turned off...

...any ideas why this might be happening...?

They perform very well otherwise.

When uncoupled from them, and being used as a straight integrated amp, the Cambridge doesn't emit the same crack when turned off.

Dougie.

 

I would guess it is the cambridge causing it. When used as an integrated, you are using a different part of the cambridge amp. This probably has a relay disconnecting the speakers at power on/off for just this reason.

 

It tends not to be to much of problem if you always make certain the vol pot is at zero.
If you still suffer .... it could be a cap problem...bothe bits of kit are getting to the age where it might be a useful exercise changing them.

 

Thanks for the input - but when you say "useful excercise changing them..." do you mean the caps, or the kit...???

 

The resovoir caps.....I'm the type of person who thinks you got the kit cause you liked it and rather than shell out a load of dosh for some new kit you would rathervstay in with a hot soldering iron.

of course this may not solve your problem with the thump....but the crimsons must be the best part of 20 years old ? Any cap of that age has started to dry out ...the also have a limited life span. This is dependant upon the spec of the cap what voltage they have been run at and their age. Most caps are good for a hundred thousand hours or so ...assuming a conservative usage within the middle of there spec. If you listen say four hours a day everyday for 20 years ....the caps running above spec you could have them run the equivalent of 100,000hrs easily.

As to swapping them ...its relatively simple but get the best you can afford.

 

Zanash that is one scary arsed picture

 

Can't you just turn off the power amps first?

 

That was what I was about to say. If I turn my pre-amp off with the power amp on it sends a nasty noise to the speakers too.

 

That is one of my cats just about to sneeze......but yes a birds eye view!

she's very sweet and only gets red eye when she has drunk to much!