Marshall 1960B cab......

1960B cab should be fine... try it with a different head...

Personally I can't stand the JCM900s.

Are you using an external EQ?
 
I agree with Xenophobe, try an external eq before plunking out the cash for a new cab. A good eq will always help your amp sound better.

If the eq doesn't get the job done, try the oversized version of the Mesa Rectifier 4x12 (the straight one would actually be better for lows than the angled one, by the way) should solve your problems.
It's also loaded with Celestion Vintage 30's, which are the best speakers for metal, in my opinion.

If this cab doesn't fix your problem, you need a new head unit.
 
A lot of people use the Boss EQ with great success... The Furman PQ-3 is also pretty popular....

It's a lot cheaper to try one from Gutiar Center and if you don't get the sound you're looking for, return it...

Just a thought...
 
Originally posted by xenophobe
A lot of people use the Boss EQ with great success... The Furman PQ-3 is also pretty popular....

It's a lot cheaper to try one from Gutiar Center and if you don't get the sound you're looking for, return it...

Just a thought...

I use the Boss GE-7 with my Mark IV (despite the fact that it already has a 5-band built in :D). It works great, it's good on batteries, and it's quite tough.
 
JCM900's are a tad bit shite in my opinion, but it might be the speakers. I have one cab with GT-75's and another with old (proper, not the reissue) greenbacks. Together they sound good :)

I don't use any EQ's either, just preamp+power amp. The cabs are fine, and I get a good bottom end out of it (nice n clear, defined) and I tune to B...
 
JCM900 and later stuff just sucks. Mass produced, cheapest quality junk. The 900's and later have tube preamps, but their plate voltage is so low, they need to use diode clipping to get distortion...

You're paying for sweat shop build quality and getting charged for the Marshall name.

Actually, the Marshall cabs sound okay with a good pre/power amp setup... Nothing wrong with that...

A lot of companies are doing the speaker mixing... Mesa has been doing that for a long time... I haven't tried the 75's/30s mixed yet, but they're getting good reviews...