For some time,Triode Electronics has been offering a 30W "Universal" SE transformer that nominally has a 1250 ohm primary impedance, but can do 5k if the 16 ohm tap is used at 8 ohms. It looks like an interesting candidate for output in a 813 "Super Schade" amp I've been considering. The price is about 10 bucks more than a Hammond. Has anyone tried this one? They're on sale now.
"but can do 5k if the 16 ohm tap is used at 8 ohms"
???? Uh, Wouldn't that be 625 Ohms primary with 8 Ohms on the 16 Ohm tap???
???? Uh, Wouldn't that be 625 Ohms primary with 8 Ohms on the 16 Ohm tap???
That's what i get for posting when I should have been sleeping. Indeed, the maximum I could squeeze out of this transformer would be a 2.5k primary impedance for an 8 ohm load - too bad, as it looks to be an authoritative chunk of iron for the money, with an impressive bias current rating. On the other hand, this high current rating may mean it's deficient in the inductance department. Back to the drawing board - I'll probably call Edcor and ask what kind of designs they have in their vaults. I'm looking for a transformer with 5k impedance that will stand up to the voltage swing associated with 700V B+,with at least 120 mA bias current capability. I'm in no big hurry, as I have many projects in line ahead of this one (an 813 pentode-mode "Super Schade"), but it would be nice to have the means at hand when I finally get that uncontrollable urge.
Last edited:
- Status
- Not open for further replies.