Tube DIY Asylum

What about tiny DC imbalance?

24.106.50.158

[ Follow Ups ] [ Post Followup ] [ Thread: Display All Email ] [ Tube DIY Asylum ]

KurtP

(A)

In Reply to: I had the same experience. posted by sser2 on March 12, 2007 at 13:23:38:

The Amity/Karna designs rely on a shared cathode resistor with a dual triode PP topology. Assuming the triodes are perfectly matched, I will get no DC imbalance.
What kind of real world triode-triode matching can I expect (lets assume JJ ECC99 for now), and what will a "no DC imbalance" transformer allow me to operate under?
Or would I be better off with separate cathode resistors, one of which is adjustable?

Follow Ups:

In my experience, - sser2 14:00:01 03/12/07 (0)
HA-107 will take 1-2 mA imbalance in the primary. My driver circuit is a pair of 45 with a common cathode resistor. I matched tubes as best as I could, and then compensated for the remaining difference with additional small resistor in one of the cathodes. Due to drift, there could be 0.5 - 1 mA unbalanced current, but I did not notice any deterioration.

This post is made possible by the generous support of people like you and our sponsors:

Sonic Craft

You can not post to an archived thread.