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B200s Question?

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RandallRG:
I just got my B200s in today. As I was told this is the way to hook it up with my MP-1 & to also be in "Stereo" with BOTH of my 4x12 8ohm cabs? Output "A"&"B" from my MP-1 to Channel "A&B" "In" of my B200s. Then Channel "A" Out to 1 of my 4x12 Cabs & then Channel "B" Out to my other 4x12 Cab. This way BOTH "A&B" are being used. When I have Channel "A' hooked up (by itself) to 1 cab it works fine. If I unhook or take out Channel "A" & put it in Channel "B" & run it to 1 cab it also works this way. Now if I hook up BOTH "A&B" & run BOTH "A&B" outs of my B200s to BOTH of my cabs ONLY 1 Channel & 1 of my Cabs work? The other channel has NO volume coming out of it.
I checked my MP-1 & BOTH "A&B" Outs work fine on it. Any info would be appreciated...Thanks! Steve   :dunno:

rnolan:
Hey Steve,  :whoohoo!: :thumb-up: . You are connecting it properly. From what you posted, both channels on the the B200s are working (i.e. A or B to cab "1" with the same speaker lead, both work). So it's either a problem with the other speaker lead (most likely culprit) or an issue with cab "2". Try A (or B) to cab "2" but with the lead that you know works, if this works then it's a speaker lead problem, if not there's an issue with cab 2 (most likely input jack).
Note: I'm assuming you are using good quality "speaker" leads ? and not shielded guitar input leads (these are not designed to take the current). Also it's very unusual to "shield" a speaker lead and speaker leads use much thicker gauge wire (to cope with the current). I find that 20amp or 15amp power cable works well for speaker leads. ADA recommends 12 to 16 gauge speaker cable (see manual attached)
Cheers R

RandallRG:
Hey Rich how ya doing? I am using 12 gauge cables. I also double checked both outputs (separately) on my MP1 & they are both working properly. When I check each of my cabs (separately) they to are working fine also. The speakers are the original Randall Jags (8ohm) that Eminence made for them back in the day. All 8 speakers are in great shape. I have not had any issues with either of my Randall Cabs since I got them. I took the cover off of my B200s to check out the board etc just to see if I noticed anything "burnt" or maybe a solder joint that was broken or cracked. It looks pretty good to me but since both of my cabs work fine I still think it has something to do with the amp? Hope all is well buddy... :metal:

rnolan:
Hey Steve, well that's a bit more perplexing  :???:
So please confirm:
B200s A to cab 1 works (nothing plugged into B out), B200s B to cab 2 works (nothing plugged into A out), when both A and B outs plugged in (which were both working) no sound ? If this is the case, then it's more MJMP territory, however, if so, you could re-flow the board that connects to the output jacks (can't hurt). It may be the output jacks need replacing ? (it's like when you have both A and B plugged in, the amp thinks both (A & B) have nothing plugged in and it turns the channels off (again see manual for running just one channel). It could just be that your output jacks need a good clean with contact cleaner ? And they tend to be the highest "wear" spot on B200s.

Hey buddy, very cold here this time of year, but all is well  :thumb-up: we'll get you sorted out, but it should have just worked !! You may need to replace your output jacks (jump that bridge if we need to) but MikeB did this recently so we can talk you through it if required.

MarshallJMP:
Seems more to me like an input problem,which input always works,A or B?

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