Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Solid State Talk all about solid state amplification.

solid state amp warm-up time, myth or fact?
solid state amp warm-up time, myth or fact?
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 16th December 2012, 11:19 AM   #101
ferret is offline ferret  South Africa
diyAudio Member
ferret's Avatar
Join Date: Jul 2008
Location: Pretoria, South Africa
Hi All. I have a Bedini 25.25 Class-A power amp. I bought it 2nd hand in 1984, and never switched it off. After almost 14 years I noticed the one channel was louder than the other - a cap in the feedforward circuit (J Bedini's words) had gone soft. Replaced it on both channels and never looked back. Eventually had to replace the reservoir caps (7200uF x2) with Philips 10 000uF (with 0.1 & 1uF bypass caps). 3 years ago a lightning strike put paid to the amp. A good friend (Isis Amp designer) repaired it for me - I already had the new transistors (MJ802 to replace the 2N3055H, & BC560 to replace MPSA transistors on the input voltage multiplier etc). No resistors were replaced. Alan's comment was when he switched it on the sound was very "grainy". He left it for an hour and then started listening and the graininess was gone; massive sound stage, definition etc. When I put it back in my system I switched it on and walked away - past experience. 1 hour later bliss. AAMOI the Bedini runs at roughly 55C. The MJ802s made a massive improvement to the the bass definition, the top end and overall speed (attack) of the system. The mid-range was considerably better than previously. No doubt the 24/7 on for so many years had helped the components degrade and the sound to change, but we don't always notice the change as it happens gradually.

I have not been using my system as much as I used to, and the electricity supplier has hiked their tariffs somewhat, so I only switch on when I'm going to relax and listen - I still leave it for at least a half-hour before I try listening, else it sounds grainy; and this includes the AudioLab 8200CDQ source. Like a car engine, electronics operate optimally at a specific temperature, and need a little time time to settle in when new. Maybe some top notch engineers can explain it to us, but for now I'll just enjoy the music.
Ferret. - There are only 10 types of people. Those who understand binary and those who don't.

Last edited by ferret; 16th December 2012 at 11:24 AM. Reason: readability; added some commas
  Reply With Quote


solid state amp warm-up time, myth or fact?Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
TDA1541A - Double Crown - Myth or Fact - How to Test poynton Digital Line Level 9 18th June 2009 12:32 PM
Off topic: SAF........ fact or myth???? rabbitz Multi-Way 19 14th April 2004 11:24 PM
The Solid State Wiki - Your solid state reference guide Jason Solid State 0 25th June 2002 06:26 PM

New To Site? Need Help?

All times are GMT. The time now is 11:16 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 16.67%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio