 
|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
|
|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
In Reply to: Have you real world experience with tuning these tubes? posted by wheezer on June 09, 2004 at 12:41:46:
But only with E188CC "red serie" Valvo, E188CC Siemens and CCa Siemens that I have. Common cathode, concertina phase splitter, cascode, all DIY. Not my favorites, thought - don`t use them no more. Almost all "Siemens" tubes (few left) cheaply sold to friend, left with only 30 or so NOS Valvos (actually `64 Philips)- too expensive for tweaking...
Follow Ups:
A little different than the 6922..
Have you toyed with differnt Vp and Ik, if so where YOU prefer them and why?
Lets say, for example 90V 3mA or 9ma? 60V 2.5mA etc.
The choice of operating point is a "art of compromise" with many "goals" in mind (min. distortion, min. noise, input overload margin, output swing, etc.) and limitations - available B+, longevity, R or CCS loading, type of circuit, usage, even standard resistor values:-). It can be even specific "sound" in combination with other tubes. No "universal" answer. But, I avoided higher currents, and 110-130V "area" with Ia~5mA with Ug about -3...-3,5V or 85V/6mA/-2V for smaller signals, even 102V/3mA/-3V, etc.
I'm not sure I follow the last statement, regarding what to avoid or what use?? There are two tubes wired in parallel for the output in the preamp.
is to axe the cathode bypass caps. With the plates tied together it seems they reduce but 2nd order distortion but increase higher order. Since you can afford the slight loss of gain do give this a try and report back.Russ
This post is made possible by the generous support of people like you and our sponsors:
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2025, Audio Asylum, all rights reserved ]
