Well was there any mueller coned greenbacks?? I was thinking the change to the lighter grey cones w no doping around dustcap was after the magnet cover color change. Is this right?? Soundboy George?
Congrats! That's got to sound really sweet with the BJA!
Um, man figure that shit out before you hurt that wonderful head you have sitting on top of it.
I'm thinking it's 16 ohms. It can only be 16 or 4 with those speakers.
Do this...plug a cable into the cab jack. Use a multimeter set to Ohms and connect one lead to the tip of the cable, and the other to the sleeve. It's going to read around 16, or 4.
Just looking at your jack socket, it could be wired up incorrectly. When the wiring is blue and brown, the brown is positive. So that means the brown should be at the tip of the jack socket, not the blue...
Instead of re-wiring your cabinet to 4 ohms, I'd STRONGLY urge you to just pull your outer two power tubes instead, for two reasons:
1. When you pull two power tubes, the impedance is also halved, so to run your 16 ohm cabinet, you set your amp to 8 ohms, which I believe is present on Scandinavian models
2. These amps kick out a helluva lot more than 100w under load. I've seen numbers as high as 210w with 6550 power tubes. You greatly reduce the risk of blowing up your amp by pulling a couple tubes
And also, NEVER mismatch impedance on a Marshall, something bad WILL happen. If you do decide to just pull two tubes, your impedance will be correct
I'd be real careful about "CRANKING" that 2203 through that cab that is only rated at 100 watts! I'm kinda surprised that with all the well seasoned, knowledgeable folks who've replied here, that they all seem to have missed the "JMP 2203" part of your first post. It may be likely that they became so focused on the coolness of the cabinet that they inadvertently overlooked or missed that fact!
Either way, I've certainly seen a fair number of greenback cabs blown with a 100 watt head. Now, if you don't run your amp insanely flat out cranked into power tube overdrive/distortion, that's a different story, but where's the fun in that! I think you need a matching "B" cabinet to be safe and hey, then your impedance will correct wit two 16 ohm boxes!
Thanks for the observation, but I'm confused. Isn't the negative here on the tip and the positive on the sleeve?
I would still highly recommend pulling tubes with the MV at 5. I know with my 2203, 5 is still EXTREMELY loud, and right at the point of power tube break up, which I would guesstimate to be around 100-120w of output. And besides, it's a lot quicker pulling two tubes than rewiring the entire cabinet. 1 minute vs 1 hour. Just make sure you pull either V5 and V8 OR V6 and V7Thanks guys! That's defintely another idea to ponder. I might have not explained myself very well when I said "crank it up" I still rely mostly on preamp distortion, right now I'm only playing on 2 on the volume knob but, at the very, very most, I'd be going up to 5 or so. Would I be still at risk of throwing more than 100w into the cab?
I would still highly recommend pulling tubes with the MV at 5. I know with my 2203, 5 is still EXTREMELY loud, and right at the point of power tube break up, which I would guesstimate to be around 100-120w of output. And besides, it's a lot quicker pulling two tubes than rewiring the entire cabinet. 1 minute vs 1 hour. Just make sure you pull either V5 and V8 OR V6 and V7
These 100w heads were designed to be ran as full stacks, and should be ran as such if you wish to keep your nice Celestions original.