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I'm not sure this is the right forum thread, but nothing seemed to fit exactly, and this is the place where I think people would understand what I'm trying to do. Bear With Me Please, it takes some explanation to get to the Crux of my issue, and even though I understand a lot, there are a lot of things (hardware especially) where I feel like a complete amateur.

I have a new Job: Digitization Specialist at the Archives and Special Collections at a University
I take old media in multiple formats and digitize them for Preservation.

The person who vacated the position before me, was a MAC user, and although I'm agnostic when it comes to the PC/MAC debate I've typically been a PC user for budgetary reasons. So they had just ordered a new Power Mac before I came on the scene. One of my primary responsibilities is Audio Restoration and Editing; in fact, I think it is my skill with audio that got me the job. One of my pet projects is Restoration of Quadraphonic Audio from Vinyl LP's from the 70's. So I have some Surround Sound Speakers that, in the past I've brought into my places of employment just for listening. Here I have a chance to use them for some fun projects.

Granted, I know this isn't the best equipment for doing what I'm doing, but just work with me under the assumption that there's no budget right now to get the proper equipment.

The Speakers are a Dell Branded MMS-5650 speaker system. They connect to the computer with three 3.5mm stereo connectors. A green one for the Front Speakers, A Black one for the Rear Speakers and a Yellow one for the Center and Sub.

This has worked for every PC I've used, desktop or laptop for the past 6 years, there have been corresponding jacks on the computers.
This MAC however only has an SPD/IF mini jack for Multi Channel Audio.

So I purchased a Small and Cheap Surround receiver. (Sherwood Netboxx R-904N)
The trick then is to be able to connect the speakers to the receiver. I purchased some stereo 3.5mm jacks and wired them with hookup wire which is bare on the end so I can connect them to the binding posts on the back of the receiver. This works great for the Front, Center, and Surround Speakers, but I'm having a problem with the Sub pre-out.

The sub pre-out is an RCA jack, so I wired one of the 3.5mm jacks so that it has two wires with bare ends for the Center binding post, and two wires that I connected to an RCA connector. I thought this would work, because the Sub is powered; but, I think I've done something wrong. If I have the RCA connector plugged into the the SUB pre-out jack when I power on the Receiver. The receiver just turns itself off.

Would having the positive and negative reversed cause this? I have it wired so the post is the signal and the ring is the ground. Is that correct?

I'm sure I'm overlooking something. Any help would be appreciated.
 

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I'm sure I'm overlooking something. Any help would be appreciated.
I'm somewhat surprised that it is working well for the other speakers.

The output from the back of the PC is "line level". The dell speaker system is expecting line level for all 6 of the inputs. You've connected 5 of them to the binding posts on the receiver, which is no longer line level...it's now been amplified. Probably no big deal unless you turn the volume up.

You probably want to connect them instead to the "pre-out" jacks on the receiver (assuming it has them).

Anyway, back to the real problem.

I think what you've done is connected one of the speaker outs to the sub out because you are sharing a wire. That's probably shorting something, causing the receiver to turn off.
 

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I'm somewhat surprised that it is working well for the other speakers.

The output from the back of the PC is "line level". The dell speaker system is expecting line level for all 6 of the inputs. You've connected 5 of them to the binding posts on the receiver, which is no longer line level...it's now been amplified. Probably no big deal unless you turn the volume up.

You probably want to connect them instead to the "pre-out" jacks on the receiver (assuming it has them).

Anyway, back to the real problem.

I think what you've done is connected one of the speaker outs to the sub out because you are sharing a wire. That's probably shorting something, causing the receiver to turn off.
This Receiver is small, so it has no pre-out jacks, except the Sub.
I pulled my custom Center/Sub cable off and checked it with a multi-meter, the only shared wire is the ground, which I didn't think would be a problem.

I am keeping the volume low. I work in a Library.
 

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I pulled my custom Center/Sub cable off and checked it with a multi-meter, the only shared wire is the ground, which I didn't think would be a problem.
So, you don't think it would be a problem...Have you tried connecting it to just the sub and not the center to see if the sub works by itself? If it does, then the shared ground (which maybe shouldn't really be shared?) is clearly the problem.
 

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What university are you performing archiving for? We just started production archiving media at Indiana University. It's a very nice setup with 15 Studer 1/4" and 1/2" players, 15 turntables, 12 DATs, 12 Tascam cassettes, 10 DVD, 1" Sony, 2" Sony, 24 VCRs, 8- EMT turntables for 78rpm on our mass production side. We're using NOA digitizing systems and RME ASE/EBU PCI 32-ch 192Khz mixer cards. IU also has another department for digitizing other media which doesn't lend itself to mass processing (wire recording, wax cylinder, lacquer disc...).
 

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So My options are buy new speakers, or buy An External Sound card.
The External sound card option seems the best, as I discovered the SPD/IF which is supposed to be giving me the multi-channel signal is lying and only giving me stereo. It's Dolby Digital Stereo or DTS Stereo, but stereo nonetheless.

And from all the research I've done today, trying to figure this out, I've decided that Macs and Surround sound pretend to go together, but just don't.

@kjfalls I'm at Utah Valley University, and it sounds like you have a lot more toys than we do.
 

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So My options are buy new speakers, or buy An External Sound card.
The External sound card option seems the best, as I discovered the SPD/IF which is supposed to be giving me the multi-channel signal is lying and only giving me stereo. It's Dolby Digital Stereo or DTS Stereo, but stereo nonetheless.

And from all the research I've done today, trying to figure this out, I've decided that Macs and Surround sound pretend to go together, but just don't.


@kjfalls I'm at Utah Valley University, and it sounds like you have a lot more toys than we do.
IU been working on it for some time and have a substantial amount of collections. Michael Casey wrote a 125 page paper outlining what was needed, what the issues were and what depts. had media requiring immediate attention and how much. All dept with collections have been cataloging and prioritizing for over a year. It should be a fun ride.
 
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