NAD - Amp Geeks Have A Read ;-)

craig

Well-Known Member
#1
I recently got a new amp, its a Marshall JTM 60, but it is not a typical JTM60. The previous owner had it modified to sound like a Freidman and it sounds great!!

I am very lucky, I was storing this amp for a friend and when he came over he said "how do you like the Marshall" told him that it's great and he says "keep it man, it's a gift, its a one off amp and I was gonna sell it, rather see it get used by someone i know"

Here is the technical stuff (from the guy my friend bought it off)

Marshall JTM60 valve combo 1995 with 'Friedman' style professional mods.
In excellent condition with Celestion Heritage G12 speaker. I bought this for gigging in tight spaces, where I couldn't fit my Friedman head and 2x12 cab. It really sounds a level above a standard JTM 60, having more depth to the overdrive sound, with less fizz or the 'boxiness' of a combo.
"Condition: Used: JTM60 modified with all the changes needed to match a Friedman Smallbox. Sounds amazing! Number of Channels: 2.
Friedman Modifications, Amplifier Type: Valve, Number of Speakers: 1 Early 1995 JTM 60 - Well not anymore!
I owned this amp and thought it to be a great little combo -and then I bought a Friedman Smallbox 50 for £2800 and obviously then there was no comparison. I discussed the differences with well a known local boutique amp builder and having looked closely at the JTM circuit said 'I can make this sound way better by making all the same changes to the circuit that Friedman have made to a Marshall circuit to come up with the Smallbox 50.' So why wouldn't we! I don't understand any of this but this is what he did First he vented the top of the case to remove any heat issues that might arise. Plate resistors were increased in value from 100k to 320k. I preamp valve removed from the circuit which was making it 'fizzy'. The clean channel is a 1968 Plexi clean in the way it now works. The gain control was changed from 1meg to 500k and the Master Volume reduced to 250k. This gives much more control over finding the 'sweet spot' and is no longer 'on/off!' The gain channel has an extra half valve added for smoother more controlled gain. This is now much more JMP Mk 2 Master Volume. Now has a Celestion Heritage 12" speaker for that vintage sound. New salt and pepper front grill. Fully serviced and biased. With parallel and series effect loops, DI output and a Presence control on the rear panel this amp has been transformed and sounds amazing. Foot switch for channel select. Quiet enough to play at home but loud enough to gig with all-in a small package.
Oh and put it though a 2x12 and you won’t stop smiling!!! The work cost a lot of money which I am not looking to recoup. We wanted to see what was possible and are thrilled with the results such that he has now added this mod to his list of available works he will do for clients.


Amazing friend, anyway here it is:

jtm60.jpg jtm.jpg
 
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