My guess is that the two cabs will sound no different if they both have the 12Ts. If the 2000 has different drivers, the 12T may well suit heavy rock/metal better anyway. Just my opinion, but I’d find better use for my $300; though I haven’t a/b’d them like you should be able to.

I prefer the amp setup with a parallel pair of speaker outs, and a selector to adjust the output transformer to 4/8/16, rather than the separate jacks. The only problem is that the old Marshalls had the worst selector design ever made. It fell out of mine regularly, usually at gigs, leaving me with suddenly no bass output and possibly giving the OPT a hard time too. Marshall could and should have sorted this by fitting a proper octal socket rather than going for separate outjacks, but that’s just my op.

I’m going on memory and I may be wrong so check what I write with what you see, star…

They might both have the Celestion-Rola G12T-75 drivers (x4 = 300W) and, if your 800 cab is 16ohm, then I’d guess they are 16ohm drivers wired as a pair each in series and the two pairs wired together in parallel, total impedance 16ohm.

The 2000 cab has options on choice of driver, so you’d need to see inside. The other difference, IIRC, is that the 2000 has the “Slash” modification of three different impedances; 16ohm (as above), 4ohm (each pair in parallel, then the pairs wired together parallel) and 2x8ohm stereo (one amp for each pair of 12s).

If the 2000 has the same drivers then it’ll be a more versatile cab but sound pretty much the same. If different drivers are in there, then expect a different sound. The G12T is a good driver for the type of music you play.

Would you have to sell your 800 cab to finance the 2000, or do you think it’s an either/or because you only have one 16ohm out on the amp? I’m not familiar with the TSL; Marshalls I know of have the 4/8/16 selector and a parallel pair of outputs. If the TSL has an 8ohm jack out and a separate 16ohm jack out, then you can still run both the 800 and 2000 cabs together, provided they’re both 16ohm cabs:-

Simply take an amp-speaker cable and put it into the 8ohm output of your TSL head, then connect it to the JCM800 cab. Daisy-chain from the cab’s other jack socket (again, using amp-speaker cable) into the JCM2000’s 16ohm input. The 16ohm 800cab is connected in parallel to the 2000 cab set at 16ohm so your amp “sees” a total impedance of 8ohm, which is what you’ve chosen as your output.

I wish I could see a pic of the amp’s backside to be sure of all this, and the 2000 cab needs looking over to see if it’s as I describe. Can you come back with more info? Especially, does the TSL100 have a 16ohm speaker out and a seperate out labelled 8ohm?

What drivers do they have in each of the cabs? do you know the speaker types???