Cable recommendation for long distance between PC and DAC

Those USB active repeaters are not great, they still still have loss and dropouts at that distance.

rca (analog) should be kept as short as possible. extending the range while still in digital domain is optimal

a great solution would be to use a USB over cat5. cat5 patch cables are cheap and your good for over 200ft.

TCP/IP gives you perfect packets & galvanic isolation from PC.

startech & icron make enterprise grade converters that people love for audio, they are ultra low noise. PS Audio even makes something called lanrover that's a similar solution, expensive though

ultimately I think this is your best bet. cheap ebough and you may find an increase in fidelity. I found a darker background with my icron USB over cat5.

https://www.ebay.com/itm/Active-4-P...o-50M-with-power-supply/272736023759?NAV=HOME
 
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I think I will try this -- just to confirm, an optical cable like the one I linked will plug into the SPDIF connector? I don't have an "optical" out.

Looks like water under the bridge at this point.

I presumed since you linked in an optical cable that was the type of S/PDIF output you had. If the S/PDIF output and input connections are not optical/Toslink then an optical/Toslink cable won't work.

Just FWIW, S/PDIF actually refers to the protocol and specifications. For consumer goods, the interconnection type for S/PDIF is normally either electrical/coaxial or optical/Toslink, sometimes both are present.

If you actually have the phono-type (RCA) coaxial connectors I'd probably have used that. A component video cable (or any 75-ohm type coax with phono/RCA connectors/adapters) generally works well.
 
[I'm curious, why would you think its better to run a long analog cable which is susceptible to all kinds of interference and degradation which never get corrected instead of a long digital run which isn't susceptible to interference, has error correction, is simply moving data, and can't color the sound in transmission until it gets converted to analog?]

I thought about that later, I have no technical basis. Just thought it would be better. And the RCA cable already there. All you are doing is replacing computer DAC with external one. So the hookup is known to work.

I don't like either solution. To me it depends on the investment. How much do you want to spend - how important is it?
 
As to the long analog cable runs, I have no expertise but I do have experience using some (as is mentioned by others here too). If a quality double-shielded cable is used, such as for component video or a digital-grade cable, the shielding is great and the capacitance of the cable is low. The cables linked in post #18 should be perfectly fine. I use 12-foot shielded cables to connect a preamp to an amp (so I can keep the speaker cables short), with no deterioration in sound that I can detect. Botrytis appears to have the same experience (post #9). Moreover, the line-level output from the DAC will be even higher signal levels than the preamp outputs the Botrytis and I are using, rendering any noise that does get through to a lower S/N ratio.

I also suspect (no engineer here) that any errors that don't get corrected properly in the digital domain have the possibility of causing big affects on decoding to analog, depending where the error is (nearer the least significant bit (LSB), or nearer the most significant bit (MSB)). In contrast, noise in analog circuits, if the S/N is high, is quite low.
 
I've got the original Cambridge Audio DacMagic (2009) and think I've got it set up correctly, but I'm not getting any sound. I found the manual online and followed the set up instructions pretty closely.

1) I connected the RCA cables and ran them to the open connectors on my receiver, Tape 2
2) Before powering on the DAC, I connected the USB cable between the the DAC in and PC out.
3) I powered on and saw that the sound card recognized the DAC as "C-Media USB Headphone Set", which is what the manual said it would name it. I then disabled the other sound outputs, as directed by the manual.
4) I opened up YouTube and started Ted Nugent - Stranglehold... well, because.
5) I set the Selector on the front to USB and the incoming sample rate is illuminated at 48. (see picture)
6) After getting no sound, I swapped input connectors from DAC into Tape 2, cassette player into Tape 1 (worked fine) to DAC into Tape 1, cassette player into Tape 2 (again worked fine). So I think I have disqualified anything wrong with the receiver.

I know the PC is playing because when I open the sound window and C-Media USB Headphone Set is has a moving meter showing music playing (see picture). I was also able to change the output from 48000 Hz to 44100 Hz and back in the sound settings, and the DAC showed the level move from 48 to 44 and back.

Anything obvious that I've done incorrectly? Or is something wrong with the DAC? Should I try using DeOxit with swab to clean the DAC RCA connectors?

Thanks in advance for any thoughts/advice.
 

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Sounds like it. Do you know its history? Also, did you check if by some chance volume is muted on the PC? I've just tried and the green level meter is moving while the volume is muted.

I don't know any history -- my brother received it as part of a trade and didn't need it, so he shipped it off to me without setting up himself. I did check the muting and it was not muted.

I forgot to mention one other thing:

I did download the latest driver update 4.12 to add compatibility with Windows 10 which I am using. I have the CA Control Panel that I can open from my notification bar, but when I open, it shows "no devices connected". I am going to dig a little more into this to see why it won't recognize the DAC.
 
To check the functionality of the DAC, can you hook up a reliable digital source to one of the non-USB inputs? Either optical or coax from a CDP, or if lacking other digital sources, the optical or coax outputs from the back of a HDTV.

If they work, then the problem is either in the PC or the USB part of the DAC, or in PC set up issues, and you won't be spinning your wheels on the latter, without a better narrowing down if the problem likely lies there.
 
To check the functionality of the DAC, can you hook up a reliable digital source to one of the non-USB inputs? Either optical or coax from a CDP, or if lacking other digital sources, the optical or coax outputs from the back of a HDTV.

If they work, then the problem is either in the PC or the USB part of the DAC, or in PC set up issues, and you won't be spinning your wheels on the latter, without a better narrowing down if the problem likely lies there.

I don't have a CD player, and the 25 ft RCA cables won't reach the nearest HDTV in my house. In a pinch I could bring in my garage receiver and speakers (more portable) and set up.

I did find a Dynex digital optical cable and hooked up from the S/PDIF output to the DAC, and got the same results: the DAC showed an incoming sample rate of 48 and, when playing a YouTube video, could see that the RealTek HD Audio Manager was playing music. Feeling my way through this, but wouldn't this indicate that it's not an issue with the USB part of the DAC, but maybe the sound card/RCA connectors?
 
I can also bring in the garage receiver and speakers and use different RCA cables to eliminate the possibility that there might be something wrong with the new cables I purchased yesterday (or that they might be too long?).
 
I can also bring in the garage receiver and speakers and use different RCA cables to eliminate the possibility that there might be something wrong with the new cables I purchased yesterday (or that they might be too long?).

I can say with 100% certainty the length itself is NOT why you have no sound.
 
You could also test the cables by temporarily using them in place of those between the tape deck and receiver, without hauling in all that other stuff.
 
And, if round about you do end up connecting to the TV digital output, you must ensure the digital output of the TV is set to send PCM, not Bitstream. Your stereo DAC will not work with a Bitstream output from the TV. That could give a misleading assessment/diagnosis.
 
I agree with what the others have said above, with the proviso that since your DAC does indicate it is locking on signal, it seems something recognizable is coming to it via USB. To me, it seems incredibly unlikely the RCA cables are the issue.

I fear that you can't narrow down your problem unless you test the DAC via one of its other inputs, using a digital source that is not your PC. But another possibility that might shed some light is to use a different sound card if you have access to one.

Your garage system is a possibility, but if I recall, it does not have any digital outputs, so I assume you are talking hooking up the DAC to the TV, and then the DAC to your NAD receiver via RCAs. It is a compact receiver so not so much to move, and you can skip moving the speakers if you have headphones to plug into the NAD.
 
You could also test the cables by temporarily using them in place of those between the tape deck and receiver, without hauling in all that other stuff.

Great idea, thank you, and the cables tested fine running from cassette player to receiver.

I would say it is your internal soundcard having issues. Can you listen to it with headphones to make sure it is working?

I agree with whoaru99....

Unfortunately, the original DacMagic doesn't have a designated headphone output. I found a 3.5mm Female to 2RCA Male cable, plugged in my headphones and tried both the left and right RCA connectors with the DAC's Coaxial output connector (after disconnecting the RCA cables from the RCA outs), and no luck. After thinking about this more, I am not sure this 3.5mm Female to 2RCA Male cable would work for a digital out, would it? I may have a digital audio cable (SPDIF) but am not sure what I'd run and connect it to to test.

I did plug my headphones directly into the PC headphone jack and could listen to the YouTube video playing.
 
I agree with what the others have said above, with the proviso that since your DAC does indicate it is locking on signal, it seems something recognizable is coming to it via USB. To me, it seems incredibly unlikely the RCA cables are the issue.

I fear that you can't narrow down your problem unless you test the DAC via one of its other inputs, using a digital source that is not your PC. But another possibility that might shed some light is to use a different sound card if you have access to one.

Your garage system is a possibility, but if I recall, it does not have any digital outputs, so I assume you are talking hooking up the DAC to the TV, and then the DAC to your NAD receiver via RCAs. It is a compact receiver so not so much to move, and you can skip moving the speakers if you have headphones to plug into the NAD.

Would the connection run like this?

TV -> optical cable -> DAC -> RCA -> NAD -> headphone

And, if round about you do end up connecting to the TV digital output, you must ensure the digital output of the TV is set to send PCM, not Bitstream. Your stereo DAC will not work with a Bitstream output from the TV. That could give a misleading assessment/diagnosis.

Thank you for this tip -- I will go into settings and make sure to send PCM.
 
I think I may have exhausted potential solutions to test:

1) I deleted the driver update that is supposed to allow Windows 10 to work with USB 2.0 and the more current CA DAC's. Because the original DacMagic only functions at USB 1.0, I thought deleting the software and driver might wipe the slate clean. After restarting the PC, I followed instructions to establish connection via USB and the PC immediately recognized the DAC as the default USB sound device. Again, the DAC showed a 48000 Hz rate but nothing going out to the receive.

2) Even though my laptop is also Windows 10, I thought I'd take a shot with it, especially it being a newer machine. The set up was the same and a lot faster, but results were the same -- nothing going out to the receiver.

3) I brought my NAD receiver in from the garage and took it, headphones, the DAC, and Toslink cable to the HDTV in our living room. I set the TV to utilize the digital out instead of the TV speakers, then switched to send PCM instead of Bitstream. Ran toslink into DAC via digital in #1, ran RCA's from DAC to CD in on NAD, set to CD mode on NAD, plugged in my headphones, turned on DAC, set source to digital #1... and nothing. Switched to FM and headphones worked fine, so no problem there.

4) My PC upstairs is running Windows 8 so set up with PC to DAC via USB, DAC to NAD via RCA cables, and listened through headphones. Again, nothing.

I guess the only thing that could be wrong from here is that something is wrong with my USB cable and Toslink cable, but I don't have any other digital application to test them with.

I've been feeding all of the things I've tried onto the Cambridge Audio Technical Support site, so hopefully they can come back and offer a solution. Otherwise, I am guessing something has gone bad with the sound card or RCA connectors.
 
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