TUBE AMP CORNER
Amp Repair
David Brand alias The G-man
Copyright 2001 - Cosmic Debris Musicians Magazine
Reasonable expectations or How I learned to stop worrying about Amp repair.
Years ago when I mentioned musicians and amp repair to the tech of all tech"s Peter Koopmans, he would
run looking for wolfbane and garlic to hang around his neck. Even though I don't fully agree with him
some customers are blissfully unaware of the obstacles that we face in servicing their amp.
One of the things musicians fear the most is A.I.R.S. (amp in repair shop) How long will it take?
What will it cost? Will it still sound the same? How will I survive? I hope the following serves as a
guide to help understand as well as minimize downtime and the accompanying sleepless nights.
1. Communicate fault. First of all can the problem be demonstrated. Sure, a dead amp is obvious but
the more information the tech has the faster things can get done.
2. Schematics. I have thousands of schematics. I might not have the one for your amp. Some companies
take a week to send a schematic, some 6 weeks or more. Most manufacturers will supply you with one by
mail or on their website. E-mail me for addresses.
3. Parts. Ditto about the time 1-6 weeks.
4. Obsolete parts. Obsolete transistors are a hassle. If you are lucky the manufacturer may have a
replacement. If not we have to figure out a suitable match.
5. Tubes If you have a tube amp it doesn't hurt to have spare tubes especially if yours are hard to
find i.e. Ampeg 12DW7 or a 7591A , Sunn or Ampeg 6550A or 7027A.
6. Intermittent faults. Intermittent problems are the worst. They come and go driving the owner and
the amp guy nuts. The key here is info. How often does it happen, for how long anything like if it
takes an hour to happen what volume is all really helpful.
7. Cold solder joints. Can cause intermittent faults hard to trace.
8. Rush jobs. Sooner or later along comes the rush job. It's supposed to go to the head of the line.
Trouble is all the other people have been waiting as well. We do try to assist working musicians ASAP
9. Rain hail sleet and snow. Just seeing if anyone's still awake
10. Not enough hours in day .Ditto
I recently had the pleasure of doing sound for my buddy Richard Francoeur's #40 bash at the Branch 10
Legion in Nanaimo Some really great jammers were there including on guitars Brad Ney, Don Wilke,
Little Davey, with Jim Cole holding down bass duty and Pat Hovis, Ron Hawkins, Keith Cyr and
Pat Stuart on the revolving drum stool. Richard thrilled the crowd with vocals on All along the
Watchtower and a good time was had by all.
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Website by: Guy Langlois - Webmeister/Publisher Cosmic Debris, 610 Lambert Ave, Nanaimo, BC, V9R 3N8