New Old Amp Day: My Jtm60 3x10 Also Known As Jtm 610

Igor_torcamaniac

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My FX loop worked OK, until I put a cable in it. It started crackling from that moment. When I opened the amp, I cleaned the FX connectors with contact cleaner and that fixed it.
I always have a patch cable at hand, just in case...
Indeed the boost channel is somewhat usable when you keep the gain low.

I changed all 4 jacks in FX Loop with Neutrik.
Anyway, I use some pedals in Serial Loop and Parallel is always patched, because I like the sound of the amp with Parallel Mix pot to max better.
 

EvoRider

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Hate to drag up a old post but was wandering how it has worked out...
I recently ordered a jtm 60 1x12 and am waiting for it to be delivered.. I haven’t had a Marshall in years...
 

IOSEPHVS

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Nice find. I am looking for a JTM60 or JCM600 head. The heat problems on some of the JTM60 series amps might be related to not all of them being vented out the top of the cabinet. I have seen some with top vents, and some without. I have a JCM602 which is vented. The JTM60 and the JCM600 series are only cosmetically different, and all of the PCBs in my 602 are labeled JTM60. I am surprised that yours is running 6L6s. Mine has not been modified, and I have never had a problem with it. They are loaded with features, and I have found that mine sounds best with minimal preamp settings, and the power section cranked at about 7.5/10.
 

Dawgfanjeff

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I am an original owner of my JTM 60. I put it aside for a few years after some reliability issues (fuse replacements) but am looking to resurrect it again and get it running. I was always concerned about that heat issue, and can't say that my issues with it are heat related, but just in case, I fashioned a shield from an old thin license plate and covered it with adhesive flexible heat shielding tape. The whole arrangement shares screws with the cage to mount it. I think I'll shield the transformer adjacent to the tubes, too.
 

stephen santamaria

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Last May during one of Melbourne's many lock downs, I bought a JTM60 3x10 from a friend who owns a music shop. Never tried it but did it to help his store out. I replaced the Svetlana EL34s and had it biased. The tech says it has to be biased hot to get the best tones out of it. I currently play my Wolfgang Special HT thru the OD channel and have the following settings: gain 7-8 (10 o'clock) ; vol 10; bass 0; mid and treble 10; reverb 0; presence on full; mv at 4, or if no one's home, 6. To my ears, it has a live Angus Rock or Bust kinda vibe. For some strange reason, sometimes i have to run it bass 1, mid 3.5, treble on 8.5 and presence between 4 and max to sound similar. Don't know if its the amp or the Wolfgang pickups or the fact that I have slight ringing in my ears. It never sounds the same 2 days in a row unlike my fav setup, Tech 21 Plexi fly rig, which nails it every time.

would appreciate some thoughts....
 

Igor_torcamaniac

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Last May during one of Melbourne's many lock downs, I bought a JTM60 3x10 from a friend who owns a music shop. Never tried it but did it to help his store out. I replaced the Svetlana EL34s and had it biased. The tech says it has to be biased hot to get the best tones out of it. I currently play my Wolfgang Special HT thru the OD channel and have the following settings: gain 7-8 (10 o'clock) ; vol 10; bass 0; mid and treble 10; reverb 0; presence on full; mv at 4, or if no one's home, 6. To my ears, it has a live Angus Rock or Bust kinda vibe. For some strange reason, sometimes i have to run it bass 1, mid 3.5, treble on 8.5 and presence between 4 and max to sound similar. Don't know if its the amp or the Wolfgang pickups or the fact that I have slight ringing in my ears. It never sounds the same 2 days in a row unlike my fav setup, Tech 21 Plexi fly rig, which nails it every time.

would appreciate some thoughts....
Can you test this again with both FX loops in the back always jumpered?
 


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