[Texasrocker]

Doug H., Many thanks for the heads-up on the Williamson design amps! Sounds like some of the Williamsons amps went into "DC spike mode" indeed! Thermal runaway you reckon? Since Im building a few amps in my spare-times allows (few), I will keep your points in mind!!
Luckily, in my recent barn-find of many vintage tube amps, Ive yielded several orig W-5M chassis ( all previously hacked) that still have the good orig power trans, chokes, & peerless branded output trans. All orig parts still test good. The hi-fiers on epay like those as well. Ive found in simply "parting the W-5M chassis' out", the "kit builders" back in 1957 didnt all know how to use a soldering-iron at all! Orig parts-o-plenty , simply bent around the orig terminal-strips under those "kit" chassis, and never soldered! No wonder so many "kits type" amps from those days had major probs. I figure those vintage heath amps-kit(s) in masses were brought into repair-shops back in the day, after orig purchasers completing the kits instructions, didnt work because of extremely "cold" solder joints! I really appreciate all the knowledge shared here indeed!!

Aaron, Many Thanks!!... for your info on the transformers & the resistors quality comparison questions!! Since I have some nice vintage Peerless orig OT's,etc, & many spare vintage chassis,all etc still test good vintage parts now onhand, I can build something good RIAA quality over the winter months. As for overall "quality" comparisons of the vintage Altec/Peerless ,UTC, Western Elec ,etc,branded I/O ( ultra-linear)transformers of yesteryear, Im sure Hammond , Jensen , & Sowter make just as good these days!! Im building a comp/limiter using sowters special-wound types ready for sale that hammond & jensen didnt offer.Havent completed that project yet. Time will tell, after a few of my RIAA Studios owners/customers verbal feedback on my new groundup-tube type special- builds for them. They have much-better ears( for RIAA) recording purposes quality than I do these days indeed! One example: ZZ Top pays " mucho extra" for "real" vintage trans installed on custom-builds vintage tube-type repros from vintage mfgrs schematics. My ears arent that good either!! Vintage peerless ultra-linear transformers "model numbers", stir up a big-fuss within the recording-industry pros! They can buy hammond, jensen, & sowters brands also. They prefer vintage "peerless" , & UTC ultra-linears types for some reason!?,I dunno either!...seems their ears can surely hear something my ears doesnt hear as well! ? Of course, at our ages, our ears are finely-tuned to yesterdays quality overall? Equal = burnt out loud-vol rockers!!!?? (hee hee) My old 300 w/Ampeg SVT amp ruined my hearing over all the yrs for sure!! Six good 6550s in PP can do that over 25 yrs!! Lordy mercy!
Once I fully deplete my stock of these vintage transformers, I will also be purchasing again from hammond, jensen, & sowter to complete my projects.