Would balanced cables help...?

[rkb2948]

Hello All,
 
I've currently got a pair of Rokit8s that I like quite a bit and otherwise sound fine, but both experience something that sounds a lot like computer noise traveling through the audio. It's not a constant buzz or hum, its something more random. At the moment I'm using a 3.5mm to RCA cable from my xonar DX to drive them. I've been contemplating doing something like the Lexicon alpha, which I believe is a USB DAC with balanced outputs. I also tried the onboard audio and experienced the same thing. Curiously, I also have a pair of A2s and they do not experience the noise. Any ideas on how to remedy this?
 
Thanks!

 

[NA Blur]

Going to a balanced setup will only help if you go completely balanced from DAC to Amp.  The primary cause of the noise you are hearing is most likely because of the DAC unit not the cables.
 
Do this test:
 
Start up your system listening for the noise with no music playing.  Connect a mouse and move it around.  If some of the sound can be mapped to the mouse movement then a better DAC will do the trick.
 
The sounds you are probably hearing are from the various clocks, power supplies, and other components within the PC that contribute noise to the audio output.  I heard these with my PC and going to something like the Total Bithead cured the problem.  I now use an external USB DAC and my PC audio setup is dead quiet.

 

[rkb2948]

So at the moment I'm not using balanced cables. I'm using a pretty basic 3.5mm to RCA cable to drive my speakers. Though from what you are saying it seems like moving to a USB dac instead of a soundcard would fix this problem. I just wonder if balanced outputs are necessary.

 

[NA Blur]

Balanced outputs are not necessary, but may give you a little more headroom as far as volume goes.  It is a fun aspect of the hobby, but certainly not a necessary one.

 

[Mooses9]

Balanced outputs are not necessary, but may give you a little more headroom as far as volume goes.  It is a fun aspect of the hobby, but certainly not a necessary one.

I agree. One problem with the balanced cables are that once you terminate it into balanced then you cant go back to using it out of a 3.5mm jack obviously. You csn get adapters from whiplash that go from balabced to 3 .5mm but they are 150.00.

 

[El_Doug]

That's because Whiplash is a snake-oil cable company that have 2000% markups.  If you really need an adapter, you can easily build one yourself, or buy one for $15. 
 
The odds of a different DAC fixing this problem, in and of itself, is minimal.  Yours is one of the very few cases in which going truly balanced WILL probably stop the noise, since this kind of chatter is usually picked up by single ended cables like an antenna.  To do so, you will need a balanced DAC, but you can get away with a cheap one with an opamp splitter on the back (such as an emu 0204).  I have the VXT4's, my wife has the Rockit 5's, and all our chatter problems were solved going balanced. 

 

[Mooses9]

Snake oil lol I like that.

 

[rkb2948]

Would an RCA to XLR help in any way. I got an external dac, and I'm still picking up the noise. I tried playing with a twisted pair on the RCA cables, but the distance between the monitors is too great to really have an impact...
 
Would a ground loop isolator do me any good?

 

[Speedskater]

Are your speakers and computer all plugged into the same AC power outlet strip?  As they should be.
 
Twisted pair in RCA interconnect cables is just asking for trouble. 
RCA cables need a co-ax with a heavy braided shield. Period.

 

[rkb2948]

I've tried connecting everything to the same exact power strip (computer, speakers, everything) and that doesn't seem to help. At the moment I've got my speakers hooked into one strip connected to the outlet, and another power strip that connects my computer, monitor, etc that also connects to the same outlet.

 

[duncan1]

If you are still getting interference problems after all the above advice then you should try another direction. Take out all cell-net phones / cordless phones/ radio transmitters for relaying music etc. apart from your modem.To test if it transmitted RF wise move components around to  change direction from the transmitter. Same applies to external radiated interference from radio transmitters/ emergency services beacons/ government services.etc. Its a last resort but it still comes down to either radiated or inducted or internal interference.and the lack of screening for the first 2 Just try to narrow it down.  

 

[rkb2948]

I tried a ground loop isolator and it seems to have resolved the problem. I still don't quite understand why I wouldn't hear noise on my headphone amp, but would on my desktop monitors. Irrespective I'm glad to have this solved.

 

[NA Blur]

Yay to cleaning audio.  I am glad you fixed your problem.