2. amps-preamps
  3. 1239812072

VTL ST-85 Repair

I have a 2002 VTL ST-85, which has of late been blowing the main fuse (6A, slow-blo). Rather than bring the amp to my local dealer (who would be happy to look at for at least $150), I'd like to have a go at repairing it myself. (As background, I'm an EE with some analog circuit experience.)

Most books I've found covering tube amp repair are written for guitar amps, not stereo amps, though I'm sure the principles are basically the same. As some may have already discovered, VTL is extremely restrictive about who they'll send documentation to - end users of their equipment don't qualify.

So, I'm looking for suggestions of good titles covering stereo tube amps, or perhaps specific suggestions regarding my particular problem.
melodious_vibrationz
samujohn's avatar
samujohn
291 posts
 
The VTL book (the original one if possible), and Valve Amplifiers by Morgan Jones ISBN 0-7506-4425-7.

Luke Manley is a nasty piece of work. I had VTL's but no more.Too bad cause David was an excellent designer.
melodious_vibrationz OP
4 posts
 
Thanks Oddiofyl & Samujohn for these tips.

Regarding Mr. Manley, its not hard to find some fairly venomous opinions of him at various audio sites. VTL definitely builds some sweet-sounding equipment, but seems fairly disdainful when it comes to customer service. My local dealer has even quit carrying their stuff because of the hassle. C'est la vie.

I'll definitely consider other tube manufacturers next time around.
oddiofyl's avatar
oddiofyl
3,975 posts
 
I agree Luke Manley is the rudest, most arrogant person I have ever had the displeasure of speaking to in my life. An absolutely horrible experience dealing with him after he renegged on his "lifetime warranty", what a scumbag.
dgad
782 posts
 

I had nothing but the best experience & very fast turnaround time getting service. Not only did they do the service but included a few free upgrades. I was blown away. VTL of past is something I never experienced. I had a compact 100 20 years ago with no issues. But currently my VTL equipment has received phenomenal service when needed.
hifigeek1
770 posts
 
Regarding VTL..My mom always would say if you don't have anything nice to say about someone don't say it...That being said, I would check your bridge rectifiers and make sure they are not shorted. It would be helpful if you had a Variac. That would allow you to vary the line voltage to the amp. If you can find a way to vary the line voltage and run the line at 110/115 Vac you can pull the output tubes and see if the fuse holds. Do not pull the output tubes while the amp is on. If the fuse holds you know it's an output tube. The reason for dropping the line voltage is to protect the filter caps from being put in an over voltage situation. This can happen if the output tubes are not in the amp. I don't remember what the caps are rated for. Hope that helps...G
More to discover