Krell KSA 50 PCB

still4given said:


Please tell me that mine were in that batch.

Blessings, Terry


Terry- the thought of you sitting idle and actually having time to listen to your krell is causing me distress. I can't have it. If you suspect you will need some boards-- why don't you let me send you a pair of aleph X boards, if you agree to help me out with my version (if I need it....yeah right of course I will) they will be there via fedex asap. email me offline. I have a set extra. Ok its not a krell but you already did that.
 
lgreen said:



Terry- the thought of you sitting idle and actually having time to listen to your krell is causing me distress. I can't have it. If you suspect you will need some boards-- why don't you let me send you a pair of aleph X boards, if you agree to help me out with my version (if I need it....yeah right of course I will) they will be there via fedex asap. email me offline. I have a set extra. Ok its not a krell but you already did that.


Now THAT"S what I'm talkin' about!

Bring em on.:drool:

Blessings, Terry
 
Re: Trannies

LuckyLyndy said:
Terry,
I am sure your transformers will be fine. I called Mark long distance, because I did get an answer from the ebay guy, and I am going to trade the trannies I have for the 500 VA 31-0-31V models. Better to unwrap than to wind I always say.
The build quality on these if very good, close to my Victoria Magnetics in the Pass Aleph 3.
Can anybody tell me in this epic thread if anyone has come up with some good looking chassis ideas? Where are those hearty few inspired by Peter Daniel? Maybe he can shrink the Krell Klone into a Krell Chipamp, or GRollins and BrianGT can come up with a Krell Mini-A?
Let's see someone come up with something fresh, rather than the basic chassis, or a Theta Miles ho-hum computer tower in black.
Lyndon


Good to hear it. He was always prompt with me. I am buying the 28-0-28 500vA trannies. I'm hoping I can use them as-is.

I don't remember whom it was who built one of the first amps with the gold sinks mounted horizontally but they were the same sinks I have here.

When I originally posted about these sinks I was told that 6 inches would be adequate but 8 was the safe bet.

I will see if I can find the builders thread that was started some time ago.

Edit: Found

http://www.diyaudio.com/forums/show...3160&highlight=

Same heat sinks only mounted vertically NOT horizonally.

Natural convection should help out tremendously.

When I read that thread it seems to me that he was unable to get true class A bias with that setup. Maybe I missed something. I'm not trying to be a nay-sayer. I'm hoping it will work. I would love to not use a fan but I also don't want a 2' tall amp. If you split the heatsink in half, are you planning on mounting the +rail outputs on one and the -rail outputs on the other? If there is one thing I'm learning is that heat dissapation is a vital part of making power. If you can't get rid of the heat, you can't have the current. Seems Class A is all about current. I know My Krell clone didn't begin to sound right until I got the bias up where it belongs. It's a whole different amp once you achieve that.

Blessings, Terry
 
Re: Re: Trannies

still4given said:
If you split the heatsink in half, are you planning on mounting the +rail outputs on one and the -rail outputs on the other?
Blessings, Terry


That is exactly correct. My hs are 16" long x 8" wide x 2" thick.

I dropped them off this morning to be cut in half length wise so I will have 8 x 8 inch squares 2 " thick.

I will then put 2 squares side by side to make a side wall of the chassis that is 16" long x 8 " tall but with the fins VERTICALLY oriented.

I would REALLY like to see if a single 8" section would be good for 1 channel instead of having to go 16" back on a chassis.
 
power supply

I'm about to start this project and want to put together the power supply first. I have decided to go dual mono all the way back to the cord. I have a couple of questions:

1. I will probably go with the Avel toroidal transformers which are very reasonably priced and are stocked in 25-0-25 and 30-0-30. It seems like the actual spec is somewhere in between. Is this a problem and if not which one should I go for? For a mono amp, would you go for 330VA or 500VA?

2. Can anyone give a list of the components and/or schematic used in their PS?

Thanks everyone

Philip
 
Philip-

You can go with the 500VA 25x2 transformer for a Stereo amp, or a pair of the 330VA is PLENTY for dual mono.

As for caps, Steve @ Apex.jr has some 68K screw terminal caps for 5.95 each. You can get 4 of those and parallel 2 per rail for a Stereo amp or have just 1 each per rail on each mono amp.



EDIT:

All-
I am "thinking" of mono amps but don't think the 8" tall sections of heat sink will carry a channel.

What is the expected disapation for 25 volt secondaries?
 

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Hi Still4given,
thanks for the support.
I work a LOT slower than you and my KSA Klone comes after the horn sub comes after Leach clone comes after the Sugdens comes after more house self-building.

You could have a long wait. I just did not want to miss the chance for the boards while they were available.
 
AndrewT said:
Hi Still4given,
thanks for the support.
I work a LOT slower than you and my KSA Klone comes after the horn sub comes after Leach clone comes after the Sugdens comes after more house self-building.

You could have a long wait. I just did not want to miss the chance for the boards while they were available.

Hi Andrew,

Do you HAVE to keep all your ducks in a row? Come on live a little. 😀

Blessings, Terry
 
Late comer here

I've gone back in the thread about as far as my patience will allow, but seem to be missing the essentials: whom do I contact for PCBs and whom do I contact for a parts kit? Could someone please amend the WIKI to include this info? Thanks in advance gentlemen, this one looks like a winner!

Niles
 
Thanks for the reply RABSTG.

One more if you please, just so all the info is condensed here:

It appears that the kit price is per-channel, e.g., $31x2 for a stereo amplifier, plus shipping?

And, it appears that the kit is complete for stuffing the main boards and biasing the output transistors, but does not include the output transistors or power supply components such as trannies, filter caps, recifiers etc. Is this correct?
 
That is exactly correct.

I will supply the parts for the main and driver brds only because there is a division of opinion on output devices.

The resistors with be Dales, which are the minimum audiophile grade resistors to put in this caliber amp, and the other parts were spec'ed by the brd designers and agreed upon by the members in this thread.


I'm out of town for tonight and tomorrow. I will return Sunday and make the parts order Monday.

As it appears now we have payment for 25-30 channels..