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Why would someone have cut the speaker wires (Rowe CD100D)?

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jeroen:
CD100D is working nicely but I noticed the sound was not always the greatest and I was "missing" some music in some songs. Turns out I am "missing" music when there are big differences between left and right channel (e.g. Queen Bohemian Rhapsody "little high, little low"). Music that is supposed to go just to the right channel would sound very "muffled" but the rest would sound OK.

When I looked at my speaker wiring I noticed 2 wires from the crossover board to right channel med and high speakers have been cut (W/G and W/O). O/B is still intact. Instead of W/G and W/O someone ran wires from the open terminal on left high (the same one that W/BL connects to) to the right channel med and high speakers (where W/G and W/O should connect). That seems to explain the muffled sound out of those speakers. :banghead:

The problem is, it looks like it was done quite neatly. The cut wires are tucked away neatly, the new wires have nice crimp-on connectors and it looks like this was done deliberately. I would like to try and connect the speakers back in their original configuration, but the fact that this looks like it was deliberate makes me worried. Would I risk damaging anything if I just reconnected the cut wires and removed the 2 new wires?

lilshawn:
they probably fried the right channel and instead of just moving the pink wire over to the left side speakertaps...you got this abortion.

also possible bad solder joint on the crossover board.

jeroen:
Thanks Lilshawn

I will restore the original connection and see if indeed the right channel is dead. If it is, I can restore the "abortion" or move the right channel lead over to the left while I look into repairs

If repairs are needed: the guy I bought it from may have an extra amp, if that does not solve the problem I think it is narrowed down to crossover board, right?

jeroen:
Also, is there a way to confirm whether the amp or the crossover is bad?

I measured voltage on the rail and the left channel measures 2.7-3.0 mV between purple on E6 and black on E1. I measure 3.0-3.4 mV across black on left E1 and pink on right E6. I guess differences between left and right are result of difference in equalizer setting. Would I see a much lower voltage here if the right channel was fried on the amp and does this indicate that the problem is with the crossover?

lilshawn:
really the only way to do this is to hook up a speaker to each channel and listen to it. a voltmeter isn't going to tell you much as it's not responsive enough to tell small changes in the signal.

disconnect all the internal speakers from the transformer (purple black pink) and place a single home audio or bookshelf speaker on E1 (-) and E7 (+) on the left side, and a speaker on E1 and E7 on the right. this will bypass all the speakers and crossover and connect directly to the amp output.

if it sounds normal the amp is good, check crossover for solder joint issues... if one or both sound "crunchy" or blown sounding. amp is bad, replace fuses on driver boards and transistors on that channel. don't buy cheap ebay special trannys...they are fake as, and will fry the second you plug the amp in. these transistors should cost about 30 to 40 bucks a pair.

take note, these amps don't take lightly to being messed with... they use high voltage rails and are balanced just so to work properly

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