Reverse engineering Krell KMA 160

Project is coming along nicely. I repaired the original equipment, and it works great. I'm almost finished with my first board, and the second one has a few parts on it as well.

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J A P A N E S E S E M I s

jwb said:
I am frustrated in finding replacements for 2sk163 and 2sj44. 2sk170 and 2sj74 look like good substitutes, but I need to find them from a reliable supplier, and both in the BL grade.


I can supply both K170BL and J74BL (usually).

The 2SK163 also seems available to me, but not the J44, J43 is but grade on these may or may not be selectable and may or may not be the one desired - but this can be checked.

There needs to be a reasonable quantity, unless I already have them in my bins already.

So, let me know

(bear at bearlabs dot com - for email)

_-_-bear
 
Viva la resistance. It'd done, and it works great. The only hacks I made were where I used a TO-92 (actually E-line) MOSFET where I had put a TO-220 footprint, and I accidentally specified 100V Schottky rectifiers where I really meant to use 200V. In the end I used a 1000V 1N5408G.

Note that my board has substantially better heatsinking than Krell's. The original KMA-160 must have had a reputation for blowing up the drivers. On the board I fixed, the strip of metal that passes for a heatsink runs in excess of 85C.

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Back to the listening.
 

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Because we got one for free, that was on fire, and would like a stereo amp, and if we can sell it on ebay for $300 we come out even?

Basically, I'll screw around with any circuit that comes along. Otherwise I'd be bored out of my mind.
 
I'd like to do it for the same reason one of my brothers rebuilt a '70 Dodge Challenger, a friend of mine rebuilt a '69 Camaro or my dad refinishiing antique furniture. Because it's fun, we can and we can enjoy seeing the creativity and construction of the time.

Mike