Vintage amp repair...

Any information concerning Mr.Soderburg's services still available? I have tried unsuccessfully to make contact for the last couple months.
His website is still active:
I used the email and phone # from that site. I have been very curious about his S500 series II mods. Specifically what is involved with turning it into full class A. I would certainly be intereted in any opinions from others who may have some experience around one of these.
Just made contact and amp is on it's way.
Glad it worked out. Jon is a good guy and a great tech.
I have a Pioneer Spec 4 amp that needs repair (It turns on but no sound)
Can anyone advise me of a good reliable shop I can send it to?
I am in the Tampa Bay area, but the shop does not have to be in Tampa
Hi Erlerob

If you can safely ship the Pioneer Spec 4 one guy I'd send it to Mike Bettinger from Mike is very competent with repairs and restorations. He restored a Sumo Nine for me with great results. Another repair guy that has done great work for me is Scott Gramlich of

Best of luck with the repair.