Topic: Marshall JTM 60

Anybody have any experience with these amps.  I just bought one off of a friend for $250 (too good to be true), but I couldn't pass up a Marshall tube amp for that low.  It's a two channel 112 combo.  What do you think?  Any info would be much a preciated.  Thanks in advance, ~BG~

2 (edited by NPB_EST.1979 2008-07-22 08:34:59)

Re: Marshall JTM 60

112 is great. I'm guessing it's a 60 watt?

So I'm in the same situation, being a 112 combo owner. Bigger gigs, I unplug the 12" speaker and go into a 4x12. Heads for stacks come in 100 watt and 50...so why not? Just make sure the ohms line up. Plugging the combo into a cabinet even changes the tone of the amp (for the better in IMO.) I digress.

For practice, smaller gigs, 98% of my guitar playing... all I have to carry around is my 112 combo. It beats having to lug around two pieces for a half stack you can barely turn up anyway.

- Nic from Detroit... posting on JB's Forum since 6-2-2006
Ask me about my handwound Great Lakes Guitar Pickups
Since 2010, Bonamassa fans have taken advantage of my JB friend discount = my cost + shipping. cool

Re: Marshall JTM 60

I've got the JTM 622 (2x12) that I've modded quite a bit and I love it.  The clean channel is especially good.   With a few changes, this amp is actually really good despite it's rep.

   The only thing with these amps is that they are PCB monsters (like the Vox AC30's) so they are a pain to work on should something go wrong.  To prevent that, you should seriously consider adding a fan by the tubes since the Marshall guys brain farted on this design and did not add any vents to help keep it cool and the way they have the tubes mounted below everything can lead to serious heat build up inside.

Don't play leapfrog with a unicorn

Re: Marshall JTM 60

Thanks for the advice guys.  I payed it out this weekend and it was great.  I think I'm going to look into getting that fan too.  When I started reading up on the amp... overheating was my main concern.  Beerdog80, what other mods did you do/have done to it?

5 (edited by Beerdog80 2008-07-30 18:12:06)

Re: Marshall JTM 60

Buddy_Guise wrote:

Thanks for the advice guys.  I payed it out this weekend and it was great.  I think I'm going to look into getting that fan too.  When I started reading up on the amp... overheating was my main concern.  Beerdog80, what other mods did you do/have done to it?

Changed various resisters and caps.  I don't have the values with me (I'm at work) but if you want, I'll post them up with the locations for you.  I also bypassed the clipping diodes.  that was a huge difference for the dirty channel.  I've been toying with the idea of putting rectifiers in their place...might have to try that this weekend.  The best way to get rid of that buzzsaw gain is to replace the stock tubes in V101, V102, and V103.  The stock ones were real weak but GTs, RCAs and others really clear it up a lot and give a nice, warm distortion.  JJ 83S tubes seem to be REAL muddy if your for that sound.  Just have to experiment to see what you like best.

Don't play leapfrog with a unicorn