Keeping a balanced audio signal between two monitors and PC

[seklas]

Hello everyone, first of all I'm very sorry If a thread like this already exists (I honestly couldn't find it).

Recently I bought 2x KRK Rokit 5 G3 monitors for my desktop computer setup. I bought a RCA to 1/8 TRS cable to connect them both together. However as an unbalanced output I'm getting a lot of noise/humming if I turn the knob at the back of a speaker any higher than the minimum -30dB. When left at -30dB - no noise whatsoever.

I thought that maybe I should buy another cable (Double XLR to single 1/8 TRS), but when looking more into it, I noticed that this would also turn the signal into unbalanced and I don't understand what would solve the problem, because it's not like I can connect two different TRS 1/8 into my PC simply expecting it to recognise them as left and right speaker.

Would anyone have any advice as to what I should do? Thanks a lot in advance

 

[seklas]

Your current connection method sounds like it's unbalanced anyway.

Well that's what I'm trying to figure out. RCA is an unbalanced connection, however what I am looking for is someone to tell me exactly how can I get a balanced connection. My point is that using XLR or 1/4 TRS alone won't make it balanced. There are only two ways to connection audio to the desktop 3.5mm audio jack or USB. If I'd use two XLR to TRS 1/8 cable it would still be unbalanced. If I'd connect each speaker individually, the desktop probably won't recognise them as left and right channels, but two individual devices instead, so in my understanding 3.5mm is not an option, however I have no idea what kind of device I could/should use so it would have to TRS 1/4 input ports and USB as an output.

 

[seklas]

Thank You everyone, but yeah I looked at the ground loop isolators and decided that I'd rather save up and get an audio interface, which will not have the problem, rather than trying to fix something at the cost of the quality of sound. Depending on the isolators I heard that it does decrease the quality :/

 

[seklas]

The alternative method of getting a balanced connection is by using either an active matching converter like a sonifex rb-ul1 or by using a passive transformer based system. In any case, if it is a ground loop as I suspect, going balanced won't solve it. I've been and tried it as I have both a xonar st and a balanced yellotec PUC interface. Any direct copper link to my HiFi without an isolation transformer caused noise pickup, be it balanced or unbalanced analogue, aes, spdif via coax even HDMI.

Seriously? Isn't the noise exactly the reason why people use balanced XLR or TRS instead of RCA, which is meant to be a cheaper alternative?

 

[seklas]

If it's that much of a problem, a DAC via optical is a more certain way of being rid of the noise, as there is no copper wire for the noise to transmit along.

So what you're saying is that I would need a DAC which has TRS 1/4 input and optical output? Or would any DAC with a single 3.5mm audio jack input and an optical output do the job?

 

[seklas]

Okay, I have done some testing at home with what I had. First, I tried to plug in my monitors into a different power socket - it didn't help (maybe it was still on the same power grid, I'm not too sure about the installation at home). Then I found a 3.5mm male to male cable, to one side I added a TRS 1/4 head adapter, the other I plugged straight into the motherboard, honestly there is no noise whatsoever at any volume level, even +6dB, however I only tested on one monitor as I only got one cable like this and the sound wasn't working properly. It sounded mono, kind of like when you go to your Realtek audio settings and click on voice cancellation (karaoke) option to cut out half the lyrics from any song, that's what it sounded like. I assume that's more of a software problem now. So If I would get a double TRS 1/4 to 3.5mm cable, do you guys think it would actually work, even though I should probably just get an audio interface anyways...

 

[seklas]

Thank You everyone for the input. I just wanted to conclude that the problem is solved now. I've bought the Focusrite 2i2 and connected my monitors via two separate TRS 1/4 cables. No noise is coming from them now at any volume level