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post #1 of 3 Old 02-08-2013, 06:46 AM - Thread Starter
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I am setting up my new home theater with the SC-55 and have installed a passive Jamo sub and a Jamo sub amp, connected through sub 1. I connected with a Y connector out of the SC-55 to a double audio cable and then into the right and left inputs on the sub amp. When I first turned it on, there was a hum (for about 10 seconds) and then quiet. The sub is a dual voice coil speaker and I had the voice coils jumped in parallel. Using the MCACC setup microphone, the system did not seem to detect the sub. Does MCACC check the sub? It went through the test and came back stating that the front and center speakers were out of phase, and said to check the wiring. Of course the wiring is all red to red and black to black, and it sounds fine, so I did not change anything. The speakers are B&W with dual terminals which I have jumped red to red and black to black (not bi-amped). Menu screen asks "Retry" or "Next", so I chose Next and the test continued. Since I don't have my side/rear speakers installed in my ceiling yet, the receiver blinked on those icons and then the sub icon and continued as though none of those were present (those icons disappeared).

I went into the audio menu and realized it was set up with no sub, so I changed the system to include the sub, changed the center and front speaker settings from Large to Small, and ran the test with the same result. Receiver sub crossover and sub amp crossover are set at 80. I rewired the sub speaker with the voice coils in series with the same result. Thinking that I may have blown something in the receiver when the speaker was wired in parallel, I tried receiver sub 2 with the same result. The Jamo sub amp fuse seems to be fine. My question is, Does MCACC check the sub? Is the sub so low frequency that I just won't hear it with most TV sound output? I am going to try Muse song Madness from my ipod, which should include some low frequency sound. Then I am going to install the rear ceiling speakers and rerun MCACC.

I bought this receiver as a demo model at a steep discount but with added four year warranty from Best Buy, but it did not come with a manual or the AVNavigator disc. Do I need that? I printed out the manual, and have been studying it. Also, It seems the remote they gave me (AXD7668) has a few buttons which are identified differently than in the picture in the manual. For instance, the Phase CTRL button shown in the manual is not present on my remote. There is a Phase button, which I tried, thinking maybe the receiver was set up with the speaker signal out of phase, but that button did not seem to do anything. (tried pushing Receiver button, then Phase several times). Help would be appreciated.
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post #2 of 3 Old 02-08-2013, 06:51 AM
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I don't know your particular hardware, but two things jump out at me.

The first is that you got a hum for a few seconds and then silence. That doesn't sound good.

The second is that your room correction setup doesn't detect the sub at all. That indicates a problem somewhere in the chain that you must address.

SOMETHING is borked, quite possibly the sub amp.

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post #3 of 3 Old 02-08-2013, 11:44 AM
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Probably stating the obvious here, but make sure you've hooked up to the correct output (I know, not a likely mistake, since you switched to sub 2 while troubleshooting - but just trying to cover all the bases!).


Projectors: Where there's a wall, there's a way.
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