Looking for Forte 1A 50w Class A replacement for Thiel 3.6s


After 40 years I may need to upgrade my  power amp lol.   It is a great high current 50 wpc class A , but soon it will be 45 years old.  I have not been keeping up on all the new high-end amps that can drive with high current the low impendence of the Thiel 3.6 that  will delver HQ presentation  Sure, 200 W  would be nice , but I listen low /medium levels, and don't need the demand of  5- 8 DB  more volume. 
Any 3.6 users out there with a highly musical recommendation in the 75-150 watt range, not too edgy suited for the Thiel 3.6?    PS I have the matching Forte  Model 2 pre-amp , all Nelson Pass builds  from mid 80s. 
 
gomemore3
Gents thanks an for the input.
1. I will  look  at and join the Thiel owners page..
 2.  I had  a serious  capable technology guy of  the past 40 years re-bias  in the last 6 months, did  some refresh and it operating great , my concern if i send to Jon and spend $800 and the transistors go, I  believe we are done... finee,    correct?  maybe not
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my concern if i send to Jon and spend $800 and the transistors go, I believe we are done... finee,   correct? maybe not



If they are not available any more I'm sure there are substitutes that are probably even better today. Jon will know, ask him.

Cheers George