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Author Topic: Why would someone have cut the speaker wires (Rowe CD100D)?  (Read 1585 times)

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jeroen

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Why would someone have cut the speaker wires (Rowe CD100D)?
« on: October 05, 2021, 05:08:30 pm »
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?
« Last Edit: October 05, 2021, 05:10:17 pm by jeroen »

lilshawn

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Re: Why would someone have cut the speaker wires (Rowe CD100D)?
« Reply #1 on: October 05, 2021, 10:15:32 pm »
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

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Re: Why would someone have cut the speaker wires (Rowe CD100D)?
« Reply #2 on: October 06, 2021, 06:29:46 am »
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

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Re: Why would someone have cut the speaker wires (Rowe CD100D)?
« Reply #3 on: October 06, 2021, 12:53:51 pm »
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

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Re: Why would someone have cut the speaker wires (Rowe CD100D)?
« Reply #4 on: October 06, 2021, 02:54:09 pm »
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

jeroen

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Re: Why would someone have cut the speaker wires (Rowe CD100D)?
« Reply #5 on: October 06, 2021, 06:36:59 pm »
Thanks Lilshawn, great advice, will do that next. One question: disconnect all speakers from the transformer just means remove purple black pink from E6, E1, E6, right?

Before I saw your message I did some additional trouble shooting along the same lines you suggested: I disconnected the wires between left tweeter and right speakers (the "solution" from a previous owner). Now only the left speakers should be working (other than the woofers)
Then I disconnected the pink and purple wires and then connected just the purple wire (with black still on E1): with purple on E6 on either left or right I get a good signal to my left speakers
I can't do the same with the pink wire, as the wires from the crossover to the right speakers (downstream of pink) are broken (I just hear the woofers when I do this)

But based on these results I would say the amp is good (left and right E6 have good signal) and left side of crossover is good.

Next step: restore the original connection downstream of pink to the 2 right speakers (the 2 wires that have been cut). If all is good, the reason for cutting the wires is a mystery but I am a happy man. If after restoring the connections a similar test with pink gives bad sound from left and right E6, I know the problem is in the crossover

Would you agree that it is safe to assume the amp is fine?

jeroen

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Re: Why would someone have cut the speaker wires (Rowe CD100D)?
« Reply #6 on: October 07, 2021, 12:08:35 pm »
Update: per Lilshawn's suggestion, disconnected internal speakers, connected 2 external speakers on E5/E1 (they were small speakers, did not want to blow them up). Sounds perfect. So amp is definitely good.

Next step: this weekend I will restore the original connections from cross-over board to right speakers. If that does not sound good, I know it has to be the crossover.

jeroen

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Re: Why would someone have cut the speaker wires (Rowe CD100D)?
« Reply #7 on: October 07, 2021, 06:25:17 pm »
Had some extra time today so restored the original wiring. Everything sounds good :D. Not sure why they cut them in the first place. Keeping fingers crossed that I am not damaging anything....

lilshawn

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Re: Why would someone have cut the speaker wires (Rowe CD100D)?
« Reply #8 on: October 10, 2021, 06:14:33 pm »
Had some extra time today so restored the original wiring. Everything sounds good :D. Not sure why they cut them in the first place. Keeping fingers crossed that I am not damaging anything....

Man, I dunno about the things some people do.

Maybe they chopped them and moved them to put some other speakers on that channel.  :dunno