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Krell KSA-50s service manual, anyone? Much appreciated

polmuaddib

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If you have it or any info on how to get it.
Thank you!
 

Slayer

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polmuaddib

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Thanks. But this is for KSA-50, not for 50s. Looks like there isn't one online...
 

DSJR

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I don't think the original version *that* complex in original form, unlike the 50S which scared the poo out of me ;) It's only the transformer and large supply caps that bulk it out - oh and the fan cooled heat sinks too. A pal lightly updated a 100 and it was mainly the row of 'Roe' encapsulated caps that he needed to change I think.

If yours has been got at by an amateur third party, HiFi News did an appreciation of one with a few pics that a UK reviewer (I know who) had butchered and which was made safe before testing.

Sorry this doesn't answer your question.

You'll need to join up to download, but try here :D


Good luck. These are now vintage collectors items and holding value now.
 

Mart68

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I e-mailed Krell and they sent me the schematic for the KSA50S. I don't think a full service manual is available.

What problem are you having with it?
 

sq225917

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They were noted for the sliding bias tracking circuit playing up. The 50s isn't a patch on the 50, same for all the s models.
 

Mart68

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. The 50s isn't a patch on the 50, same for all the s models.
I don't know about the other 'S' models but have to strongly disagree with regards to the 50S.

Please don't make me lug one along tomorrow to prove you wrong ;)
 

Katji

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s

Krell Industries KSA-50s Owner's Reference Manual​

https://www.manualslib.com/manual/498126/Krell-Industries-Ksa-50s.html

1651928856798.png
 

sq225917

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I don't know about the other 'S' models but have to strongly disagree with regards to the 50S.

Please don't make me lug one along tomorrow to prove you wrong ;)
I've had two freshly rebuilt units on the floor at the same time, same updated parts almost the same bias settings. The standard 50 just did it better. Not a patch on the 200 though..
 
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polmuaddib

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I e-mailed Krell and they sent me the schematic for the KSA50S. I don't think a full service manual is available.

What problem are you having with it?
Thanks for helping. It is for a friend. He searched everywhere and then I offered to ask here.
 

Mart68

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Thanks for helping. It is for a friend. He searched everywhere and then I offered to ask here.
Just wondered what was up with it as I have two of them and they both had the same issue, once it was diagnosed it was an easy fix.
 

sq225917

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In the original full bias class A circuit its nearly always a driver board taking out a bias resistor and killing an output transistor. Or a psu cap spilling its guts.

In the S its usually the input tracking circuit that drives the sliding bias doing the same thing.
 

Dolor

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Hi,

is here any one who could help.
I was looking for a owner manual or similar for a Krell KSA-100 MK2.
Really everything else could be found belonging to the other products from Krell.
Huge Database about amps, preamps etc. for every product line in more than 40 years.
But not the MK2.
Even Krell emailed me and told me that they couldn’t help me.
Just an handmade drawing is available in the internet. Meh

Can someone probably provide an owner manual to me and to the world?

Thanks in advance

Dolor
 

sq225917

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I can probably dig out the mk1 schematic and circuit doc. The mk2 was a different animal though. The mk1 was full time class A, the mk2 aiui used their sliding bias circuit.

Pm me if you want it, I defo had it 5 years ago when I rebuilt a ksa200 mk1, should still be on file.
 
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