|
Vintage Asylum Classic gear from yesteryear; vintage audio standing the test of time. |
|
|
|
Vintage Asylum Classic gear from yesteryear; vintage audio standing the test of time. |
|
In Reply to: RE: Two Eico HF-12s, versus one Eico HF-81, my thoughts.... posted by drlowmu on June 7, 2007 at 07:13:24:
Jeff,
For a preamp I run the 12B4 at about Vp 250V Ip 25ma, A bit hot. Others have backed off on it. I have a mockup of a 12A4 DCed to a 12B4 as an input but I get some arching. A 12B4 as a concertina measures to the end of the earth and back. Perfect square waves the whole bit.
I don't have any op points in mind for the EF86 or E55L at this point; it’s just an idea and not close to reality. IT would be cool to run the G2 off of a dedicated supply too. The usual 1meg limiting resistor cause wildly varing op points.
I can understand the noise issues on the grids but with the EL84 being sensitive a better balance can be obtained with fixed (adjustable) bias.
Did you look though the projects on the Hoshimoto site? They have some nice data. It makes for easy comparison between KT88s, EL34s and EL84s.
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- RE: Two Eico HF-12s, versus one Eico HF-81, my thoughts.... - Scholl 06/7/0708:36:14 06/7/07 (0)
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2025, Audio Asylum, all rights reserved ]
