NAD 2100 upgrades

By April 4, 2016Audio

so I have two NAD 2100s in for upgrade, one had a cracked PCB and is now up and working, all with new electrolytic capacitors throughout- The Panasonic 10k uf 80v from Digikey drop right in perfectly.

However the second NAD is being somewhat recalcitrant and I have pulled out nearly all the driver and and output transistors to try and find the problem. The issue is with the High Voltage rails,

and now I have it coming out of protection, which led me to look into transistor equivalents and replacements. Although the main outputs (Sanken) are also avialable from Digikey, some others, such as the 2SB922

appear to be unobtainable, and have very few appropriate substitutes.