[PlanetCCRMA] Re: PlanetCCRMA digest, Vol 1 #1426 - 6 msgs

[David Ford]

Mark Shuford wrote:

>On Fri, 23 Sep 2005 12:00:05 -0700
>planetccrma-request@ccrma.Stanford.EDU wrote:
>
>  
>
>>   4. Re: Delta 1010 buzzing - update (Joe Hartley)
>>
>>--__--__--
>>
>>Message: 4
>>Date: Fri, 23 Sep 2005 12:38:55 -0400
>>From: Joe Hartley <jh@brainiac.com>
>>To: planetccrma@ccrma.Stanford.EDU
>>Subject: Re: [PlanetCCRMA] Delta 1010 buzzing - update
>>
>>On Mon, 19 Sep 2005 18:46:50 -0400
>>Joe Hartley <jh@brainiac.com> wrote:
>>    
>>
>>>A woeful thing has happened at the studio - the Delta 1010 has a
>>>horrendous buzz on all 8 output channels.
>>>
>>>I remembered that there was a discussion on this list a year or so
>>>back about replacing capacitors, so I checked the archives, then
>>>cracked the cover of the 1010's breakout panel, to find...  no
>>>obvious sign of a problem.
>>>      
>>>
>>I finally had the chance today to pull the 1010 breakout box from the
>>rack and really open it up.  Turns out that under the flat black metal
>>strip screwed to the top of the daughterboard is a 2200uF 25v cap with
>>a bulging top and just a little brown ick on the top of it.
>>
>>So on the one hand...  phew, I can fix this myself.  On the other hand
>>(there's a fist - obscure Jona Lewie reference), I'm disappointed I've
>>got to replace it after a relatively short period of ownership (3
>>years or so).
>>
>>Thanks to all on the list who helped out!
>>
>>-- 
>>======================================================================
>>       Joe Hartley - UNIX/network Consultant - jh@brainiac.com
>>Without deviation from the norm, "progress" is not possible. - FZappa
>>    
>>
>>End of PlanetCCRMA Digest
>>
>>    
>>
>
>
>I wasn't around for the 1010 buzzing issue discussion which involved
>those capacitors. Was the advices to replace the caps w/ better quality
>caps? Was their any suggestion of using different ratings, particularly
>voltage? 
>
>I don't know what function the caps served in the circuit... but I'm
>thinking filter caps. A higher voltage rating could be a good
>idea... esp. if the originals were good quality caps. If the originals
>were marginal or junk then some good caps of the original values should
>do it -- if the circuit design didn't de-rate those caps too much.
>
>It's been a while since I worked hands-on w/ circuits so I'm not sure
>who's making the best caps at this time.
>
>
>cheers,
>mark
>
>
>
>  
>
Can I add to what Mark says with a vote for the temerature rating of 
caps - temperature ratings are often overlooked - yet heat is what kill 
caps most.

David