Hi guys ,..........man I'm a sucker for amps even though I have everything I need. Saw this yesterday and went to give it a try at great volumes and it sounded frikken good ! I was surprised !....especially when I was plugged into the guys Slash beat up AV cab. Had one years ago and it sounded squishy but now I know why ,........when I got back home,..couldn't play it loud because of neighbors and I heard why people say they can sound fizzy, they really need to be loud ,....not crazy loud but loud !........and the effects loop works great. Saw a post on another Forum saying that the JCM800's are getting out of reach price wise and I suspect that those 900's MKIII and SL-X will also be going up in value in the next years , not as much as a JMP or 800 but higher than they are today . A member here was saying that the Preamp volume acts on all frequencies and the Sensitivity knob acts on high frenquencies ,....If I dial both knobs at noon ,....I get 2204-ish crunch , not exactly but close ,...........today I'm gonna roll preamp tubes to see what happens .
I have one 2204 JMP and a JCM800 and they both do sound good at low volume but the SL-X needs some volume ,..........hope I can find a place where I can ripp !
I've had both, and actually prefer the 50w version of the SL-X. As you've stated, they need to be turned up to sound good, and I could never get the same "feel" from the 100w version. I'd pull the chassis and check the condition of BR3 and the larger electrolytic cap next to it, they are known to fail. If you're lucky, they've already been replaced.
Just installed some old Westinghouse in V1 and V2 and put a 7025 in V3 and 7025A in V4 and man what a difference !.........the amp sounds good at low volume without fizz so I'm very happy, it sounds more open and warmer ,....have plenty of bottom end and even need to bring up the treble knob , not experiencing what I've read about some being very bright ,....the EQ works really well .
i think if you find the right set of tubes and properly bias it, it will greatly improve tone. I've "heard" before that these amp were biased cold from the factory, but who knows. I actually own a 4100 with JJ E34L & ECC83S tubes (biased to about 68-70%) and it's beefy as hell, not shrill or fuzzy at all.
Played the 2500 SLX for years. Awesome amp. Loved the 2nd channel volume. it takes care of any need for a volume boost for leads.