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Need to recap my Classe Audio DR-8 Amps - need suggestions

I recently purchased two Classe Audio DR-8 amps. The amps were barely used and are in mint condition, but I think I need to have them recapped due to being over 20 years old. I am guessing Classe Audio would be the best place to have the amps recapped, but I am not sure. Any suggestions where to have the amps recapped and what I should expect to pay?

Also should I recap my DR-5 pre amp?

Thanks.
kdross
georgehifi's avatar
georgehifi
10,312 posts
 
kdross
I recently purchased two Classe Audio DR-8 amps. The amps were barely used and are in mint condition, but I think I need to have them recapped due to being over 20 years old.
No not really seeing they were barley used this should be tried first, all they would need is to be powered up very slowly 10-20 at a time over a few hours so all the electrolytic caps can "form" themselves again.
This can only be done by a tech using a big variac that can handle the power, other wise the variac will blow.

There is plenty to read on "forming old electrolytic caps" on Google.

Cheers George
kdross OP
8 posts
 
Thank you for the responses.  My amps do not make any noise and are very quiet.  No popping, humming, etc.  My concern is after 1-2 days of connecting my DR-8 Classe Amps and DR-5 pre amp to my Thiel CS2 speakers, the woofers on both speakers went and need to be replaced.  I do not know what caused the woofers to go.  But I did play the speakers at a rather loud volume after installing the amps and wonder if that did my speakers in.  Just do not want to cause more damage to my speakers or amps.  
georgeab
95 posts
 
Sorry to hear about your woofers. I would put a voltmeter on the amplifier outputs and see if you have a significant DC offset. That is something that has the potential to take out woofers. If you have DC offset, it could be from something internally faulty or it could just need adjusting. Pretty straightforward procedure, put meter on outputs and tweak pot until it reads 0 +/- 1mV. Here is the procedure from the DR-8 service manual: https://www.hifiengine.com/manual_library/classe-audio/dr-8.shtml
Looks like same procedure as on my DR-10 which I have owned since new. I have no indication that my caps need replacing and I have been using for some 27 years now.

georgehifi's avatar
georgehifi
10,312 posts
 
1: If you have any dc offset coming from the amp, you may hear it at switch on by a good hefty thump through the speakers.

2: And if it has a constant large amount of dc offset you can as gergeab said measure it with a DMM if you have one and know how to use it.
Or after the thump look at the bass driver will be in or out a little more than where it normally sits in it's rest state with no amp on, if there is dc present.

Cheers George
garebear
1,155 posts
 

…...I had to laugh and my apology to the OP but it happens so often here that I had to say something. Jackd adds his or hers opinion that has nothing to add or do with the OP's question on capping his amps.

 I owned Classe' gear for years and gs556 adds some good information and living in Syracuse, NY ; United Radio does really nice work. I would also contact Classe' and see what they would suggest as the amps are obviously out of warranty so the one who seems to have the best approach for you would be a good starting point. Good luck and those are nice amps designed by David Reich.        

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