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kendrick crackle noise

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6/18/2000 1:40 AM

kendrick crackle noise

I am doing a some service on a 4x10 Kendrick amp,
and can not trace a crackling noice that sounds a lot like bad plate resistors , I changed all of them(1w C-Film)to 2w M-film but no dice, also checked and tightened the the tube sockets, but the puttring crackling noice is still there but not as much as when I started though, I also found some really ugly soldering in there by the way!! and the filter caps are only glued direct to the inside of the filtercap tank, no isolation! very poor work i think
anyway could this crackling be the choke or the OT, or maybe the power supply caps or the 220k parralell resistors? any ideas?
T.

6/18/2000 11:17 AM
Tom	Re: kendrick crackle noise? No ideas at all? y

6/18/2000 12:01 PM

could you give us a little more info to go on? what tubes does it use? What brand? Any you can add and we may be able to help more. once had a princeton sound like this..it was the sovtek 6V6 it was using. Bad preamp tube, cap or anything could be causing this.A little more info may help narrow it down. How many channels does it have.. if 2.. do both do it. Is it with the guitar plugged in or just sitting there making the noise
Richie{~}==:::

6/18/2000 12:19 PM

Thanks for your reply Richie!
I checked the pre amp and that seems to be ok, I have now narrowed it down to something in the power amp or power supply,the tubes are not the problem I have checked with new different ones aswell so i will now check the power amp tube sockets again and I also found a couple of bad grounding points, I also found that it had been some ground arcing between the power supply filter caps tank and one of the speaker magnets!! I Isolated it but that was not the main problem apparantly,
still weird though,I would say it is a bad designed amp! (it is supposed to be a clone of a -59 Bassman but it has 498 v on the plates!)and again lots of poor soldering! Is it true that G.Weber sold meat at doors before he started building amps??
I have also checked Keens debugging page and maybe I will get some ideas from that. Thanks .
T

6/18/2000 3:02 PM
Peter S	Are you sure that's a Kendrick amp you're talking about? All the ones I've seen have been VERY WELL CONSTRUCTED AND HIGH QUALITY. Also they never had 498 volts on the plates......more like 430VDC! Peter S

6/19/2000 12:47 AM
Tom	Yes, it is a Kendrick 4x10 bassman with effects loop made in the fall of -92, has the black kendrick speakers and soundspleasing , but no, this one is not well designed, IMHO and yes it is absolutely stock and has almost 500vdc on the plates! and lots!! of glue holding the high voltage caps if the glue would let go then the amp would turn into a deep frier! T

6/19/2000 2:42 AM

Wow Tom!
You should contact Kendrick.......maybe they'll do something for you about it. That just isnt right! I've never seen one like that. They are usually well constructed.......not as nice as a Victoria but decent. As far as high voltage caps just floating on glue........OMG!.....sounds like trouble waiting to happen! I would get some tag board and remount or terminal strips.....since the amp is almost ten years old it's about do for a recapping anyway so I would do it for sure.......but why the hell would they use a tranny that's kicking out almost 500 volts. All the ones I've seen were running at 430vdc like the originals....You could drop with a Zener. Did you buy this amp new?..just curious.

Peter S
Kimerick amps

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