 
|
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 |
208.106.0.70
I have a couple of DIY mono-block amps I had been using for Ipod head phone jack amplification that used the hi gain 6GK5 to drive the 1626 output into MQ RH-40 series output transformers.Now I am playing with them again, I need to use them with a source that will swing higher P-P voltage (don't know exactly yet the Pono line out))
So I am trying the old 6J4WA driving the 1626 (ala Darling)but I am also exploring using a 12V6 strapped triode instead of the 1626.Question #1:How to triode the 12V6? I think I just tie Screen Grid G2 to plate (4-3) and the suppressor grid is tied to cathode internally. Is that all there is to that?
Next is driver choice...My 265V B+ and 5K 40 ma OPT tells me that I need to bias the 12V6 at about 10-13v...the 6J4WA or 6GK5 is going to swing more than that so I think I want to change driver tubes.
That's OK with me :)
I'd like to stay with 6v 7-9 novel if possible. I have 12AT7 (wire center tap 6v) 6CG7 and some others so....
Question #2: What driver would you suggest for the 12V6 in this situation?Question #3: What else should I consider here? I'd really like to get these amps working great, I plan to get better speakers (Tekton) and I play mostly acoustic music.
thanks,
Robert
Edit: Here are 2 links to tube data
http://frank.pocnet.net/sheets/079/1/12V6GT.pdf
http://www.r-type.org/pdfs/1626.pdf
I had trouble linking 2 url, I'll get it figured out
Edits: 10/25/14 10/25/14 10/25/14 10/26/14Follow Ups:
If you have two 6GK5's, just rewire for two 6C4's. (Roughly equivalent to half a 6CG7)
Thanks CB, that certainly does look like a good option, especially since these are mono blocks and 1/2 a 6CG7 would be unused...dang, I have a good stock of Sylvania JAN 6CG7....
Well, I'll figure that one out.
Since I'm playing with this thing on the bench now, I'm going to try SiC Schottky on the bias (was NIMH)...and what the heck, might as well play with CCS plate load while I'm at it!
Does it look I will have any issues with my 265v B+, SiC bias and grid RL coupling? (grid choke on output tube)if I use something like the Bottlehead or KK CCS kit?
265V B+ doesn't really matter, that won't be the plate voltage.
The CCS plate load is a nice idea.
6cg7 and 12ay7 are the 2 I'd be playing with.
Thanks Paul, yeah, the 6cg7 is probably my top choice right now.
Biased at about 2 v it's really in a linear zone, about 6.5 ma idle, mu of 20.
If it's output voltage swing doesn't clip the 12V6 it should be fine.
Suggestion on driver/output tube gain structure are welcome also.
"If it's output voltage swing doesn't clip the 12V6 it should be fine."
Isn't that what you want? To be able to saturate/clip the output stage before the preamp or driver run out of steam? I design all my amps that way.
--------------------------
Buy Chinese. Bury freedom.
TK, that is a good point...I had not considered it in exactly that way but I did know I don't want to amplify driver distortion...sometimes I wonder if I'll ever get past the beginner level in this ;)
Did my description of tying the 12V6 triode sound correct?
Yes, you should only need to connect the screen to the anode. Some people use a 100 ohm resistor in-between, but I don't recall any reports or articles about this being necessary with the 6V6 (12V6).
--------------------------
Buy Chinese. Bury freedom.
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:
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2024, Audio Asylum, all rights reserved ]
