Hi, i've a Hammond 1650ka output transformer and (Za-a 3.4k, ultralinear) and i want to replace a bad outputr trasformer that i burn out. But the specs say that it fit for a quad of 6l6/EL34/6550, rated 60w. I dont'have enough space to put 4 output tubes. Which tubes fits well for a pair output tubes push-pull ultralinear mode (VDC 475v 400ma) with 3.4k impedance? Maybe KT120 or KT150?
Thanks!
Thanks!
KT120's 800ish Rp in UL config should support a 3.4K OPT as is the KT150. If you want more Class A operation, you could also consider running it in triode mode as well.
800ish as JCM800? Right?
So 3.4k UL is matching much better with kt's than EL34/6l6?
800ish as in around 800 ohms or so plate resistant. EL34 in UL is about 2X the plate resistant and will be less output power efficient then a KT120 with a 3.4K a-a OPT.