On Saturday, December 28, 2019 at 12:29:16 AM UTC-5, wrote:
Got a nice JVC A-S7 amplifier. But one of the STK0055n final ICs died. A
darlington pair. Seems most of the STK modules are no longer available.
Has anyone come up with a board that discreet components can be used on,
and will fit the original IC holes on the board?

OR

Is there a complete amp final available that can be mounted inside the
amp and just wired in to replace the ICs.

This amp is rated at 50W per channel.

This company in Ireland has them at $65 U.S. each:

https://www.electronic-spare-parts.c.../stk_0055n.htm

For that kind of change, I would think they would be Sanken new old stock and not knockoffs of some kind. I changed tons of those during the day (mostly Fisher 0080 and 0100), but even 20 years ago they were obsolete by my memory.

Alibaba lists the STK0055N for about $12 shipped:

https://www.aliexpress.com/item/32820841800.html

The one review said it worked...