Krell KSA 100mkII Clone

[AndrewT]

and I was going to use a redundant aluminium heatsink as a "jig" to drill out the To3 holes.

unsigned (too ashamed)!

[Mark A. Gulbrandsen]

Exactly. Fixtures are still very useful but have a finite life span.

Andrew... You could use that TO-3 heatsink to lay out your jig or fixture since it was accurately done... probably by CNC.

Mark

[Kusta]

Hi,
If I am late never mind! If I'm not, would be interested for board.
Thanks in any case!

[mpmarino]

Yep, your late Kusta,

or anyone else interested, for that matter...

Feel free to replace my name with yours in the Wiki. I have money flowing in other places at the moment and another amp build won't happen for a while....

maybe next year

[PWatts]

Quiet here lately..

Well I've updated the BOM with a few changes and elaborations, plus added quite an extensive Everything You Need To Know About The KSA100 Clone But Too Afraid To Ask section. It's not the basic assembly instructions, but more directly applicable to the KSA100 Mk2 and the boards and can be seen as a parahrased version of most of what has been covered on the thread so far.

Combined with the KSA50 wiki instructions it should be very easy to build.

Any comments or additions will be appreciated

[There were some errors with the jumper designators that are fixed now]

[Jozua]

Mark

I've made a payment - please check if it has arrived on your side ?

Many thanks for the willingness to assist in having the boards made. I have never seen a project move so fast.


Jozua

[Flodstroem]

I disagree to your comment regarding the 5 Amp bias set level of the mk-II . Proper bias set level should be 2.5-2.8 Amps depending on % of margin. If you meant 5 Amp peak level I agree to you but what you have specified in the BOM document could be confusing to somebody not familiar to Class-A calculation.

Here I would like to refer to some of the earlier posts designated K-Amps, AndrewT and Stuart, whom discussed the subject and cleared things out:

Stuart is right and supports Kamps. I cannot disagree that Iq=2.76A gives MORE than 100W of ClassA into 8r.

I think we are also agreed that KSA100mk2 will safely deliver a lot more than 100W into 8r. Mark has stated 160W.

I also will not/cannot dispute Kamps measurements and calculations leading to
quote:
690mv across the 1 ohm emitter resistors meant it was biased to 122 watts pure class-A into 8 ohms

On the same basis that both the KSA50mk2 and our 50 Klone will push a lot more than 50W into 8r does not stop us specifying an Iq=1.9A giving about 58W ClassA for an amp capable of a maximum of about 70W to 80W.
I think we are all agreed that our 50 Klone is fully biased to ClassA just as a Klone of the 100Mk2 biased to 2.76A will be fully biased to ClassA.

Further information on this subject is to be find in Post # 96-102

Regards

[Mark A. Gulbrandsen]

I've made a payment - please check if it has arrived on your side ?

Got it!

Thanks,
Mark

[groov]

I have not checked this board or any prior messages but does anyone knows if the pc boards have been ordered and if there is a delivery schedule?

Thanks

[Mark A. Gulbrandsen]

Yes! Boards were ordered on the 1st of DEC with a 4 week turn= around(the cheapest route). With the holidays I expect to do the shipping after Christmas and between New Years as long as delivery is not held up by the holidays. I will post when the boards arrive here and are shipped and so on.

Mark