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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

Showing 2 responses by oddiofyl

oddiofyl's avatar
oddiofyl
4,122 posts
 
First check the cathode resitor between the tube socket and the test point. I have had these go out of spec and cause the tubes to draw excessive current, blowing the main fuse. I had a few tubes get red hot and the bias seemed OK at the test point, the resistor was out of spec and was something like 18 Ohms instead of 10 Ohms.

I would never buy another VTL again, it sounded great when it worked but they don't even want to service older products.
oddiofyl's avatar
oddiofyl
4,122 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.
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