SET Asylum

RE: 2A3C

80.95.228.93

In Reply to: RE: 2A3C posted by Gerry E. on June 20, 2007 at 05:38:07

If you just drop in 2a3c tubes into the Yamamoto A-08S amp, you will most likely have to adjust the filament voltage. In my case, I had the PS, both plate and filament voltages adjusted to a correct voltage, as the Yamamoto supplied PS transformer primary was wound for 220V, our European supply PS voltage being however 230V, so for 45 tubes, I had to adjust the DC supply by means of resistors both for the plate supply, as well as the recifier tube and output tubes filament volatages, by means of resistors. For the 2a3 tube, which takes 2.5A rather than the 1.5A with the 45 tube, I simply took out the low resistance voltage dropping resistor out of the circuit and I had the correct 2.5VDC on the filaments of the 2a3c output tubes. With no other adjustments, like to the plate voltage, both of my 2a3c tubes were drawing 40 mA plate currect, which I felt was fine. For more plate current, output tube cathode resistors would have to be lowered by paralleling another resistor with it, but I did not expect this would bring better sound, except for slightly higher output power, so I did not do it.

I should ad that finally - and here comes the blasphemy now - I was less happy in with the Yamamoto A-08S than with my solidstate Pass F3 amp *in my system*, so I kept the F3 and sold the A-08S...

Follow Ups:

Post a Followup:

FAQ

Post a Message!

Forgot Password?

Moniker (Username):
Password (Optional):
	Remember my Moniker & Password (What's this?) Eat Me
E-Mail (Optional):
Subject:

Message:	(Posts are subject to Content Rules)

Optional Link URL:
Optional Link Title:
Optional Image URL:
Upload Image:
E-mail Replies:	Automagically notify you when someone responds.

To view your new posting or follow-up, click on the RELOAD or REFRESH button on your browser.