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previous: pumpstein This sounds like a *really* cool am... -- 6/13/2000 2:09 AM View Thread

Re: Help!Weird prob with "Super" DR clone!

6/14/2000 3:32 AM
Wild Bill
Re: Help!Weird prob with "Super" DR clone!
Well Mr. Pumpstein, it just sorta "grew" that way!  
It started with a junkbox OT that was heavy enough for at least 60 watts if not more that measured kinda low on the primary - 2100 ohms. That low value got me thinking about parallel tubes as a better match.  
I have just "wussed out" and abandoned the 5V6's. They worked but I had got 5V6GT's rather than 'GTA. They were lower on plate dissipation and had a tinge of blue inside from the high B+. I went with 6V6EH's by Electro Harmonix so's I could run them the way I wanted with reasonable tube life. I'm fortunate that I live in the same town as "" so I could just drive down and buy them. So much for all the money I saved on the less popular 5V6's but I figured it was worth it rather than screwing around to dial down the power.  
Not trying to brag - I'm just so pleased with the way the amp has turned out! I built it on a Hammond 17x10x3 chassis with a "cage" on top, a la some old Stromberg Carlson's. The chassis is painted gold, the top is a dark Christmas green and I put black suitcase-style equipment handles on the sides of the cage. I had done something similar before to a smaller amp that was promptly dubbed the "Toaster". This one is now the "SuperToaster"!  
I figure I'm running between 50-60 watts - I haven't measured it yet but it sounds as loud as it should to my ears. It's even more "punchy" than a regular DR - probably the cathode bias.  
If anyone has a similar low primary value OT in their junkbox I'd sure recommend giving this approach a try. It's not cost-effective for a manufacturer but as a hobby using up scrounged parts the cost is not relevant.  
The only remaining problem is some hum creeping in as you advance the reverb pot. I've tried all the standard things - this may take me a while.  
Wild Bill

pumpstein Thanks for the detailed post descri... -- 6/15/2000 2:10 AM