'Scuse me, but I've just searched my way in here from 'out there' (across the virtual pond) and have a question about the GP-11 MK IV, if I may throw in here:
I have an [b]AH250SMX[/b] (Kaman era) which I run throught a pair of Bag End S15-D cabs, and it's the best amp I've ever had. I really am having a lot of fun with it! Just yesterday I picked up another, older TE head, an [b]AH250 GP-11[/b] (it was a bargain) to have as either a backup or leave in a rehearsal space. It's considerably larger, heavier, and simpler in layout and features than the lighter, racier SMX- and has the reknown front-mounted Ultra-Violet lamp . I believe it's a MK IV, as there's no 'Balance" slider...
I did an A/B with the two heads earlier today, and noticed the SMX seems to feel tighter, has a brighter ('clearer') sound all-around, and gets apparently louder with much less turn of the Output Gain knob. I made an effort to set the graphic eq on each amp the same, and I bypassed the on-board compressor and tube blend on the SMX to try and use a similar feature-set for both amps.
The GP-11 seemed a little 'loose and wooly' in the lows compared to the the SMX, which stayed tight and clear all the way down. I'm working with the GP-11s EQ for that, and have an Ashdown 2-band compressor pedal I'm also trying with it. Seems to make a difference, they are still different but have gotten much closer to similar now with a little work. The GP-11's character is generally a touch darker than the SMX's. It'll do alright as a backup to my main rig. The blacklight is noisy and blinks a bit, so of course I'm going to have to fix that! That purple glow is just a near-mystical experience, I tell you. Fun stuff- very 80's!
One thing I like about the GP-11 is that all the peripheral functions, i.e. Send/Return, Slave Send/Ret, DI... are on the face of the amp. GK's newer models also go this route, which seems just plain sensible. I wish the SMX was also laid out this way (more like the GP-7SM)! Not a gripe though.
My point though is to see about getting a little insight on this GP-11 (ser # C4445) from some of you guys in-the-know here. I'm interested in what makes all these models different, and what advantages some models may have over others. Not to be a nut-case, but is there any kind of history of this line that gives practical differences between models, tracing the progression to the present? A timeline or similar presentation to look over in some archive?
I've also written British Audio Service, though this is a better run-down of my experience so far!
Anyhow, now that I've helped you pass a little time here, thanks for reading!
Edit... I've been playing the GP-11 some more, and that's a great amp. Another keeper.