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Issue with Krell KSA-250

Hello-

It's been a minute since I've been on the forums here, but I'm glad they are still around!

I am the second owner of a Krell KSA-250 amplifier. For the past 10 years it hasn't given me any problems. Then today, when I turned it on, it emitted a rather loud buzzing sound. This wasn't coming from the speakers (like a ground loop hum), this was a very startling almost "mechanical" buzz sound. The buzz does not stop until I turn the unit off.

I'm not sure where to start. I called my local audio repair store, but they don't work on Krell. They suggested I contact Krell, which is my next step, but seeing as I'd have to freight this for it to be repaired, I'm hoping someone here might shed some light on what's happening. I've made a short 15-second video of the issue, but I don't think I can upload it here. I'm happy to provide it though.

Any thoughts you might have would be appreciated.

Thanks,

Blake

blakeh
invalid
1,187 posts
 

@devinplombier if you ever seen what some people do to them, including some techs, you would know why. These types of repair jobs often used to end up at Krell service. They give schematics to authorized techs.

devinplombier
116 posts
 

@invalid

if you ever seen what some people do to them, including some techs

I have. And? Having schematics would help reduce honest mistakes. Not having them will not deter the botch-job cretins, since they can’t read them anyway.

These types of repair jobs often used to end up at Krell service.

More business for Krell. The problem is?

Look, suggesting that manufacturers jealously guard schematics and service manuals for the sake of product and service quality is naive nonsense. It does no such thing, in fact it makes it worse for owners who depend on professional help to keep their gear in shape. The only thing the absence of documentation achieves is to force serious folks to spend / waste a lot of time "reading" the circuits and figuring how they work. It’s not rocket science, but it is quite time-consuming.

I encourage folks to get involved with Right to Repair advocates in their state. The right to fix your gear, owned and paid for, is already the law in several states, and with everyone’s effort it will soon be in all 50 states. Thank you

https://www.repair.org/stand-up

 

blakeh OP
6 posts
 

I appreciate all the suggestions on how to make modifications to the unit, but I prefer to keep it as designed, even if there are a few minor flaws. I can tell you that Casper at Stereo Rehab has fixed these (and other Krell models) before and knows them inside and out. He was very helpful and I can't say enough about their service and knowledge. Here's what he listed as the repair:

"Krell KSA-250: service. Thermally damaged standby and relay supply dropping resistor replaced (metal film flame proof, 2w);standby primary filtering
replaced (105', 450v); thermally damaged front end supply filtering replaced (both) including armature supply rail and stand by pre-regulation supply rail (all fresh
Nichicon, 105'). Operating as designed."

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