Tweakers' Asylum

Surgery Done on Amp with PSU on Driver stage and..

213.122.236.88

[ Follow Ups ] [ Post Followup ] [ Thread: Display Email Next ] [ Tweakers' Asylum ]

mikee55

(A)

...Output stage,(I didn't get any replies last time),Hi all,just fired up Amp with 2 supplies.The first a basic supply driving the amp at low current level and second,a PI filter with 6800uf smoothy, a mains transformer and a 4700uf smoothy.An old Toroid is having its secondaries wired as a Choke.So far I havn't listened much,been busy,but so far I'm impressed,with an all round improvement.I'm thinking what my shopping list should contain.I need more than a basic PSU doing the low current business.I'm thinking on regulators and Zener for High current.Whats your views?please.
Happy listening Mikee55

Follow Ups:

Re: Surgery Done on Amp with PSU on Driver stage and.. - pkell44 17:27:04 11/30/04 (2)
IMHO I don't think much of any tfmr. used as a choke. Yes, it saves $ but I believe the iron core will cause hysterisis (will not linearly pass all frequencies). I believe in the old adage "If it's worth doing, it's worth doing to the best of your ability" (and your budget). Bite the bullet and use high quality foil wound chokes of at least 5 mH. As for the Zener rectifiers, they generate quite a few HF & RF nasties. Look at the HEXFREDs @ Digi-Key for Freds with adequate amperage/voltage rating. The factor of merit of the HEXFREDs is NOT their speed, but their soft recovery (turn off) characteristics. Other diodes have a very fast "Snap" off that generates lots of HF/RF nasties that mask fine detail resolution and transient attacks & decays. Bypass each rectifier's output with a 0.01 ceramic cap to Gd.
Happy Listening !
- Re: Surgery Done on Amp with PSU on Driver stage and.. - Wally 11:00:18 12/01/04 (1)
  I've read several posts that contradict this point on FRED speed, for example:
  http://db.audioasylum.com/cgi/m.mpl?forum=tweaks&n=107244
  http://db.audioasylum.com/cgi/m.mpl?forum=tweaks&n=56094
  Michael Percy also states, in his catalog, that "their fast response time and high current capability are desirable"
  Does anyone have an authoritive view on the importance of speed with these diodes?
  - Thanx - mikee55 10:59:06 12/02/04 (0)
    Cheers

This post is made possible by the generous support of people like you and our sponsors:

Atma-Sphere Music Systems, Inc.

You can not post to an archived thread.