|
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: Paging Drlowmu: low L, low C in phono preamp posted by nc on November 13, 2007 at 12:17:39:
Hello,Yes, I know the answer to this. Capacitor size should decrease at you get closer to the load, NEVER increase in a "low everything" supply, be it for a final output stage, a line stage, or a RIAA stage. Why??
One must think of all capacitors as being NASTY, and if we could, we would eliminate them totally, but we can not in the power supply, so I've been taught to make them as small as possible - just enough to support the circuit, maintain speed / ON-TIME current delivery, but no more than necessary.
Note: a "low everything" approach I found to be important, particularly in a tube stage drawing under 1 milliampere. Such a stage truly demands having 12 AWG (or lower) wire of the highest quality, to preserve PEAK instantaneous response to music's dynamic events. This was reported previously, and heard very clearly by me on music playback, in my 2007 Eico HF-81 mod, both to the G2 supply, and to ALL of the HF-81's various 12AX7 stages.
I listened with a 98 dB dust-cap modified JBL 123 on an open baffle, playing very percussive jazz and piano music.
ALL thinner wire "clipped off" the instantaneous peaks of hard transients, but the thicker wire got it AUDIBLY right! Ideal wire, if one can afford to use it, might be Siltech G-3, G-5, etc.
This Eico HF-81 mod of mine, due to space constraints, was compromised, using just a single Stancor C-2708 - added as a choke input filter. This part was very nice sounding in the HF-81 circuit. Palpitable mid bass.This Forum response doesn't give you exact details, but it honestly and accurately reports to you how I believe circuits should be best executed. I speak ONLY from my practical experience, and what I clearly HEARD, in 2007 with my Eico HF-81 mod. Have fun experimenting and listening !
Jeff Medwin
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- RE: Paging Drlowmu: low L, low C in phono preamp - drlowmu 11/13/0717:28:35 11/13/07 (0)
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2025, Audio Asylum, all rights reserved ]
