dexkemp

Hi there.

I am kind of new to marshall amps but I recently found out the drummer from my band has a marshall JTM amp.

There is no MKx next to the JTM logo.
The back says its a SuperBass and the serial number is : SB10084
it looks vrry old and dusty.

I haven't seen it myself but I will go and check it out I will post some foto's soon

I can't find a lot of info on the web about this amp and my question to you guys if you can tell me anything about his amp (age, value)

Thank you very much!

Marshall Amps

__________________
This advertising will not be shown in this way to registered members.
Register your free account today and become a member on Marshall Amp Forum

janarn

Should be from late '66 early '67 if it's a JTM "reverse logo".

dexkemp

Thats a reverse JTM logo right?

Anyways, the standby switch is broken and the rear panel protecting the tubes is missing. The amp sounds great to me, tough on vrrry high volumes I get an unpleasant kind of distortion (sounds like we need a doctor). at midhigh volumes I got some great thick tone out of it.
It has to be one of the best sounding amps I ever got to try.

Maybe some marshall veterans could teach me some tricks about using this amp. can anyone tell me what all the jack inserts on the front panel do?

janarn

That's a JTM "reverse logo" or "black flag" Super Bass.
A very rare and valuable Marshall amp. The sound you can get out
of that, could be posted in "the best Marshall ever" thread.

But the value of the amp (and the sound) has much to do with
original transformers and parts.
Post some pictures of the transformers and some gut shots.

The amp should sound better on high volum than medium volum,
so something is not working as it should. (could just be the tubes)

I know, I have a '68 Super Bass, and it sound great at volum 8,
but you will need an attenuator to really use the amp.

Take that amp to a good tech that knows about vintage Marshalls,
and let him check the amp. Then get the right parts to restore the amp
to original.

You can get good help and advice for that on the Plexi Palace forum,
or the Metro Amp forum.

Like all four hole Marshalls the two on the left is the "high treble" channel,
and the two on the right is the "normal channel.
The top innput on both channels will give more gain.
Try the upper left innput, set precence at 0, bass 0-3, mid 8, treble 5,
and turn up the left volume.
And start looking for an old cab with original greenbacks, that will bring
the right sound for the amp.

dexkemp

Thank you verry much Janarn.

Next time I see the amp I will take some pics of the transformers. The guy that owns the amp doesnt want me to open it up (and i can see why). He will take the amp to a tech soon.