|
Tube DIY Asylum Do It Yourself (DIY) paradise for tube and SET project builders. |
|
|
|
Tube DIY Asylum Do It Yourself (DIY) paradise for tube and SET project builders. |
|
In Reply to: Re: My 26 SE Headphone Amp Using AC Filaments – A Development? posted by fatbottle on December 4, 2006 at 06:21:22:
FB:Yes, I had tried resistor loaded grounded cathode operation of the 26, three years ago. With AC on the filaments, it hummed. I tried to use cancellation techniques based on Steve Bench's work, but could not get a quiet AC powered version.
I want to be careful about saying anything about DC powered filaments, because I have not tried them. They may be great. However, the archives of this forum and other forums are full of postings about use of 26s and the absolute need to use DC power because AC implementations are too hummy and noisey. Less than a month ago you said in a posting that you would "not go anywhere near AC", and another inmate said AC could not be done without unacceptable hum.
So, I now claim to have successfully implemented a headphone circuit with AC powered filaments. I think that is extremely rare, from all I have seen. Jose K has posted the schematic, above. It is beginner-simple, as compared to the simplest DC implementation, and with a little scrounging can be done cheaply, too.
From where I now sit, I would not turn to fiddling with DC, which I know can be done successfully based on your work and that of others. And, I am definitely not the guy who will do experiments so that I can say this method or that circuit produces hi-fi while some other one produces low-fi.
Steve Root
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- Other methods of firing the 26 filaments - Perseo 07:39:22 12/05/06 (1)
- Re: Other methods of firing the 26 filaments - fatbottle 08:15:03 12/05/06 (0)
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2025, Audio Asylum, all rights reserved ]
