Thundersteel Posted April 25, 2019 Share Posted April 25, 2019 ...and it is indeed DOA. The tubes light up, but as soon as the standby switch is flipped to "ON," there is absolutely no sound. Also, the HT fuse blows. I swapped tubes; no change. I checked the output transformer, and I'm not sure if it is the problem. The primary measures 84Ω (42Ω between ends and the center tap). What's puzzling, though, is the secondary reads very low. Between ground and the 4Ω output, I get 0.5Ω; between ground and the 8Ω output, 0.6Ω; and between ground and the 16Ω output, I get 0.8Ω. I also checked for continuity between the primary and secondary; my meter reads infinite. Any amp gurus here that can help? Link to comment Share on other sites More sharing options...
DaveH Posted April 25, 2019 Share Posted April 25, 2019 You are not going to read much on the OT secondary, your measurements sound typical. Have you tried a new set of power tubes? Link to comment Share on other sites More sharing options...
Thundersteel Posted April 25, 2019 Author Share Posted April 25, 2019 47 minutes ago, DaveH said: You are not going to read much on the OT secondary, your measurements sound typical. Have you tried a new set of power tubes? That's the first thing I did, along with replacing the HT fuse. Link to comment Share on other sites More sharing options...
tbonesullivan Posted April 25, 2019 Share Posted April 25, 2019 That's really odd. I can only think that maybe during transportation something got knocked loose. Did you ship it with the tubes installed, or packed inside the head? Link to comment Share on other sites More sharing options...
BoogieMKIIA Posted April 25, 2019 Share Posted April 25, 2019 Could be the screen resistor(s). If the old tubes are bad, those resistors may be shorted causing the fuse to keep blowing. Link to comment Share on other sites More sharing options...
Thundersteel Posted April 25, 2019 Author Share Posted April 25, 2019 9 hours ago, tbonesullivan said: That's really odd. I can only think that maybe during transportation something got knocked loose. Did you ship it with the tubes installed, or packed inside the head? With them installed--never had a problem until now. When I removed the back plate off the amp, one of the power tubes was almost completely out of its socket, and the plastic "key" was broken off. Link to comment Share on other sites More sharing options...
tbonesullivan Posted April 25, 2019 Share Posted April 25, 2019 33 minutes ago, Thundersteel said: With them installed--never had a problem until now. When I removed the back plate off the amp, one of the power tubes was almost completely out of its socket, and the plastic "key" was broken off. Marshall tube claws are beasts. I seriously can't see how a tube would be able to work its way loose during shipment in one of those. Is the key still in the socket? Otherwise I'd say that the guy who got it managed to break it off. I mainly asked because some people don't know how to put tubes in, at all, and end up screwing up the sockets. If the recipient was one of those, it can be a pain. Either way, my main suspicion is that either the receiver did something stupid to it, or it developed a cold solder joint or other issue during shipping. How is the clean mode on the DSL out of curiosity? I know on my TSL it is pretty bad. Link to comment Share on other sites More sharing options...
Thundersteel Posted April 25, 2019 Author Share Posted April 25, 2019 1 hour ago, tbonesullivan said: How is the clean mode on the DSL out of curiosity? I know on my TSL it is pretty bad. When the amp worked, the clean channel still had a bit of dirt. Anyway, I watched some Youtube videos, did what they suggested, and so far, everything checks out. It's possibly a bad main board. Regardless, Reverb said they would pay for the repairs. Now, I need to find a good amp tech! Link to comment Share on other sites More sharing options...
hamerhead Posted April 25, 2019 Share Posted April 25, 2019 I think bubs knows every tech in the country. Ask him. Link to comment Share on other sites More sharing options...
bubs_42 Posted April 25, 2019 Share Posted April 25, 2019 1 hour ago, hamerhead said: I think bubs knows every tech in the country. Ask him. @Thundersteel I actually do know one of the best, but you'll have to ship it. Link to comment Share on other sites More sharing options...
Hamer_SS_guy Posted April 25, 2019 Share Posted April 25, 2019 1 hour ago, Thundersteel said: When the amp worked, the clean channel still had a bit of dirt. I have the 6100 and 6101. The clean channel is very nice, but the amp doesn't have reverb (I use a Boss reverb with those amps). My experience was that the clean channel doesn't sound that nice with a few dirt pedals I tried. But I really like the other channels too. I use a medium "yellow" channel, rolling back the volume on the guitar to get my "clean" sound (EMG's work well with that), the "red" I use for lead. It has some nice features too. A former band member had the JCM2000 TSL, it sounded a bit glassier, but also slightly thinner to my ears, compared to the 30th Anniversary. Link to comment Share on other sites More sharing options...
tbonesullivan Posted April 25, 2019 Share Posted April 25, 2019 If you were in NJ, I would have great recommendations. I would look to see if there are any places around that are warranty service centers for Marshall, Mesa Boogie, etc. Also many custom amp builders also do repairs. Fuchs up here in NJ will fix just about any type of tube amplifier, and a lot of other things as well. Link to comment Share on other sites More sharing options...
bigolsparky Posted April 25, 2019 Share Posted April 25, 2019 3 builders in Birmingham AL. I would think there are some closer to you as well. Link to comment Share on other sites More sharing options...
Thundersteel Posted April 26, 2019 Author Share Posted April 26, 2019 I found someone local to me. I've heard good things about him, so hopefully he can figure it out. Link to comment Share on other sites More sharing options...
sixesandsevens Posted April 26, 2019 Share Posted April 26, 2019 Keep us posted. The one time I had an amp blowing fuses I was lucky enough that it was just a bad power tube. Good luck! Link to comment Share on other sites More sharing options...
Thundersteel Posted April 26, 2019 Author Share Posted April 26, 2019 2 hours ago, sixesandsevens said: Keep us posted. The one time I had an amp blowing fuses I was lucky enough that it was just a bad power tube. Good luck! I'm still thinking it's the output transformer. I told the tech what my readings were, and he said they seem too low. Hopefully, I'll find out in a week or so. Link to comment Share on other sites More sharing options...
Thundersteel Posted April 30, 2019 Author Share Posted April 30, 2019 The amp is fixed! The amp tech said something was wrong in the heater circuit (I can't remember exactly; I think maybe a shorted resistor?) which caused one of the power tubes to red plate. He had it repaired in 30 minutes! He had about 5 other DSLs in his shop with problems as well. Very nice guy to talk to. I told him I was a Marshall fan for years, then switched to Orange. It turns out he owns a couple Oranges, too, and said they were better built than Marshalls, though Orange has some shortcomings as well. Shout out: He builds amps as well as modifies therm. His company is Armored Amplification. He is/was a C-130 engine mechanic. Link to comment Share on other sites More sharing options...
tbonesullivan Posted April 30, 2019 Share Posted April 30, 2019 NICE!!! I hope he still has hearing in in both ears. I have a friend who had to work with them, and part of his duty was to literally stick his head on the engine to listen to it. He's got nerve deafness in that ear now. Glad to hear that it was an easy fix! Those are the good years for the DSL amps. The earlier ones, like the early TSL amps, can sometimes have runaway bias issues. Link to comment Share on other sites More sharing options...
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