|
Tubes Asylum Questions about tubes and gear that glows. FAQ |
|
|
|
Tubes Asylum Questions about tubes and gear that glows. FAQ |
|
In Reply to: dual Eico HF-86s/no bass posted by chopper87 on August 11, 2002 at 10:20:46:
Chopper,Probably a combination of certain old gain stage tubes and a tired power supply filter circuit. I'd change out the PS caps, first---as if they pop, they make a horrid mess.
I use Sprague ATOMS and try to go to higher voltage rated electrolytics. Don't forget to change the electrolytics & diode in your bias supply circuit, too. Those caps are just are old---and are critical for maintaining a steady idle bias. WATCH THE POLARITY OF ALL CAPS AND DIODES. I'd draw a diagram to be sure.
After the PS caps and bias caps are changed out. Check the B+ C+, & D+ voltages, as well as the NEGATIVE voltage on the fixed idle bias test points. They should be within 10-15% of nominal value.
My bet is a lot of good bass will return after these mods. Then, go after front end tubes, one-by-one.
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- Re: dual Eico HF-86s/no bass - steven oda 11:44:47 08/11/02 (5)
- Re: dual Eico HF-86s/no bass - Pland 14:38:00 08/11/02 (1)
- Re: dual Eico HF-86s/no bass - chopper87 15:08:12 08/11/02 (0)
- One other thing - steven oda 12:24:31 08/11/02 (2)
- Re: One other thing - chopper87 12:41:06 08/11/02 (1)
- Re: One other thing - steven oda 15:26:02 08/11/02 (0)
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2024, Audio Asylum, all rights reserved ]
