|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
24.184.43.67
In Reply to: RE: I get confused posted by David Smith on November 06, 2014 at 14:41:28
Yes, a quad of 6V6 should perform well at 5K+ and did not sound good at 4.3K PP as spec'ed in the ST-70 audio transformers. I recommend 6K minimum, but compromised with the Dynaco transformers I had in the parts bin'. 6V6 triode does not like same impedance as tetrode connected. And, IMO are not so great sounding UL either.
I advised Eric Kingsbury the pair he designed in the Music Machine with 6V6 in triode should be 10K P to P. Eric followed up a year later with recommending 10K audio transformers.
Follow Ups:
But pp that should be 18k to be the equivalent impedance to your ppp amps, no?
I have a pair of pp 6v6 amps with 10k opt's, I've been meaning to try the MM circuit so sounds like I should do it.
Dave
In simple terms paralleling tubes drops the impedance in half of a single tube.
Not only does it affect you output transformer choice, but it also allows you to get a away with a very simple driver stage.
dave
Right, sorry I'm confused. One tube SE - 5k. Two tubes PP - 10k. Four tubes PPP - 5k. PPP with 9k is the equivalent of PP at 18k, no? Did I misunderstand?
Dave
Correct. 9K PP is rather high. 6K-7K for PPP 6V6 triode would be best with a good balance of power & dampening factor.
~!
The Mind has No Firewall~ U.S. Army War College.
Cool, makes sense, thanks.
Dave
Post a Followup:
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: