Looking for solutions to PC noise coming through stereo monitors

[III-V]

Thinking on it more, it is likely that they are not taking an extra step in tying the 1&3 pins together so much as they are just neglecting to split the signal properly for this purpose. Regardless, the livewire interconnect I posted most likely also has this same fault as I doubt it is correctly split at this price point either. I imagine the goal for these products is just being able to make the connection and not necessarily gain any benefit from a balanced input.

So in this case, I would need to purchase a splitter, and then two separate unbal/bal RCA->XLR cables.

Maybe I will set this idea on the back burner and focus on getting the USB adapter to apple dongle to get up and running, and possibly look to an external powered dac with toslink input and balanced output as a longer term solution.

 

[Dunring]

Yes, I have a 3070. Maybe you could have a look at the attached image. Where would you suggest placing the port card?

Mine is located right there, above the shielded side of the power supply and far from the video card as I could get it. Silent noise floor from it, and the Apple USB adapter would work well there. I use the A to C 3.1 type adapter on it for standard ports. There's cards that have C and A also. I just like the chip in the Febsmart.

 

[staticV3]

Well they only have one version for sale in-house and I do not see a schematic available. If they tie the pin together it defeats the entire purpose, why would they take an extra step to do that?

Because then they can use standard coax wire instead of XLR wire. It's a cost-cutting measure.

 

[audio_tony]

@III-V As I said in my previous post (which maybe you missed?) you could use a USB to SPDIF converter like this:

CM6631A USB to I2S/SPDIF Coaxial 32Bit 192K Sound Card Digital Interface + Case | eBay

New upgraded firmware, the official version of CM6631A, finished board has been tested OK. Using CM6631A, more cost than the CM6631 chip, better performance. 1 x Black CM6631A Digital Interface USB to I2S / SPDIF Coaxial 32 / 24Bit 192K Sound Card.

www.ebay.co.uk

This has an isolation transformer which breaks any ground loops (but you would need to use it with and external DAC - not the built in DAC.

You can see the transformer just behind the SPDIF / RCA output jack.

 

[III-V]

@III-V As I said in my previous post (which maybe you missed?) you could use a USB to SPDIF converter like this:

CM6631A USB to I2S/SPDIF Coaxial 32Bit 192K Sound Card Digital Interface + Case | eBay

New upgraded firmware, the official version of CM6631A, finished board has been tested OK. Using CM6631A, more cost than the CM6631 chip, better performance. 1 x Black CM6631A Digital Interface USB to I2S / SPDIF Coaxial 32 / 24Bit 192K Sound Card.

www.ebay.co.uk

This has an isolation transformer which breaks any ground loops (but you would need to use it with and external DAC - not the built in DAC.

You can see the transformer just behind the SPDIF / RCA output jack.

I am sorry I did not respond. How would this improve upon using my existing spdif output to an external dac?

 

[staticV3]

I am sorry I did not respond. How would this improve upon using my existing spdif output to an external dac?

This would not improve upon your motherboard's built-in Toslink output in terms of noise isolation, since both solutions are electrically isolated.

 

[audio_tony]

I am sorry I did not respond. How would this improve upon using my existing spdif output to an external dac?

As staticV3 says - it wouldn't improve over the motherboard toslink, but would work if you wanted to use a coaxial spdif connection to a DAC.

In case you don't realise, spdif is either coax or toslink, however toslink is usually limited to 96k.

EDIT: SPDIF is just the protocol, COAX or TOSLINK is the transport method for that protocol. (apologies if OP already knows this).

 

[III-V]

As staticV3 says - it wouldn't improve over the motherboard toslink, but would work if you wanted to use a coaxial spdif connection to a DAC.

In case you don't realise, spdif is either coax or toslink, however toslink is usually limited to 96k.

EDIT: SPDIF is just the protocol, COAX or TOSLINK is the transport method for that protocol. (apologies if OP already knows this).

In this case I do have access to an optical spdif, and no I did not know the distinction of the protocol to transport method for the naming convention, I had just always called the fiber optic cable and port the 'toslink' and hadn't really used the term spdif until I started looking into my mobo datasheet trying to troubleshoot this noise issue. Not a lot of info on the audio so I will need to also assume the 96k limit...

Realtek ALC887 8-Channel High Definition Audio CODEC - Jack-detection, Multi-streaming, Front Panel Jack-retasking - Supports up to 24-Bit/192kHz playback

Audio Features: - LED-illuminated audio trace path design - Rear optical S/PDIF out port - Premium Japanese audio capacitors - Audio Shielding - Dedicated audio PCB layers

 

[audio_tony]

In this case I do have access to an optical spdif, and no I did not know the distinction of the protocol to transport method for the naming convention, I had just always called the fiber optic cable and port the 'toslink' and hadn't really used the term spdif until I started looking into my mobo datasheet trying to troubleshoot this noise issue. Not a lot of info on the audio so I will need to also assume the 96k limit...

A few years back I had an ASUS Crosshair V Formula-Z motherboard which claimed to have superior audio - and believe me, it did, once I eradicated the ground loops.

So I would say that your Toslink suggestion would solve your noise issue.

 

[DVDdoug]

A few years back I had an ASUS Crosshair V Formula-Z motherboard which claimed t have superior audio - and believe me, it did, once I eradicated the ground loops.

So I would say that your Toslink suggestion would solve your noise issue.

With S/PDIF you aren't using the onboard audio. You're just sending digital data to your DAC (or AVR, etc.).

But with RCA/coax you can still potentially get ground loop noise whereas optical eliminates one ground connection. (You can still get ground loops or other analog noise on the other side of the optical connection.)

 

[audio_tony]

With S/PDIF you aren't using the onboard audio. You're just sending digital data to your DAC (or AVR, etc.).

But with RCA/coax you can still potentially get ground loop noise whereas optical eliminates one ground connection. (You can still get ground loops or other analog noise on the other side of the optical connection.)

Yes I know the Toslink is not using the on board (analogue) audio.

The SPDIF signal is however still using the on board audio processing.

Of course ground loops can exist between the DAC and active speakers, but this is rarely an issue because most DACs are isolated from mains earth, and so long as they're not powered from the computers USB port they will effectively be floating.

A couple of years ago, I carried out a few tests to illustrate the effects of ground loops.

USB noise measurements

USB noise measurements, Raspberry Pi, Intel NUC, PC, USB DAC

gtkc.net

 

[pma]

Of course ground loops can exist between the DAC and active speakers, but this is rarely an issue because most DACs are isolated from mains earth, and so long as they're not powered

Many DACs, including higher class of Topping devices, are class I components with 3 prong mains plugs. And I know about several users who had troubles with it, when connected to class I PC.

 

[neRok]

Don't bother doing this, it didn't help in my situation. I even sanded off the paint at the screws!


I saw someone mention Kali. My IN-8 V2 had more hiss with RCA enabled+connected and the computer OFF, and this was connected to Topping DX3 Pro+. I got a powered interface with XLR, and they are very quiet that way.

 

[audio_tony]

Many DACs, including higher class of Topping devices, are class I components with 3 prong mains plugs. And I know about several users who had troubles with it, when connected to class I PC.

Thanks, yes I had forgotten about those!

I suppose it depends on what DAC the OP opts for really...

 

[AnalogSteph]

I was also looking at in-line ground-loop noise isolators, and I think that should work but they also impact the low frequency response of the music and introduce some additional distortion.

Try the trusty Behringer HD400 with the requisite cabling (stereo 1/8" to 2x 1/4" TS, TRS to XLR cables). Been using that for a while myself. You can also get some fairly decent audio interfaces around the $100 mark (e.g. Audiofuse 1, "old" Focusrite Scarlett gen3).

The cheapest option may be the DIY route as suggested by @staticV3.

 

[Berwhale]

@III-V - My experience...

PC (USB) + Topping D50s DAC (RCA) +Topping A50s HP Amp (RCA) + Tannoy Reveal 402 = No Noise.
PC (USB) + Topping D50s DAC (RCA) +Topping A50s HP Amp (RCA) + iLoud MTM = Noise!

The difference between the Tannoy and the iLoud monitors is the the later has a 3 pin power connector with a safety ground (as do your TV5s).

So then I tried...

PC (USB) + cheap ADUM4160 USB isolator + Topping D50s DAC (RCA) +Topping A50s HP Amp (RCA) + iLoud MTM = no noise.
PC + Toslink bracket connected to SPDIF header (Optical) + Topping D50s DAC (RCA) +Topping A50s HP Amp (RCA) + iLoud MTM = no noise.

Both solutions above work, but both also limit the sample rate for some of my FLACs. Although this was definitely not audible to me, it nagged me a little and I also longed for a simpler solution than the Topping x50 stack and all it's wires and power supplies (I also have the P50 linear PSU). So, I bought a Topping EX5 DAC/HP Amp and relegated the x50 stack for armchair use.

PC (USB) + Topping EX5 (XLR/TRS) + iLoud MTM = No Noise!

Later, I added an in-line sub (which also has 3 pin power)...

PC (USB) + Topping EX5 (XLR/TRS) + Presonus Sub8 (TRS/TRS) + iLoud MTM = Still No Noise!

If you can move to a balanced solution, it's well worth it in the longer run. The EX5 was the perfect choice for me as it has a decent DAC, HP Amp, pre-amp functionality and it remembers HP and pre-amp volumes independently.

Another benefit of moving to a single box for DAC/HP Amp and Pre-amp duties is that I can do fun things like this: Controlling PEACE/eAPO on Windows with Topping DAC/Amp Remote (or any other IR remote)

 

[III-V]

Try the trusty Behringer HD400 with the requisite cabling (stereo 1/8" to 2x 1/4" TS, TRS to XLR cables). Been using that for a while myself. You can also get some fairly decent audio interfaces around the $100 mark (e.g. Audiofuse 1, "old" Focusrite Scarlett gen3).

The cheapest option may be the DIY route as suggested by @staticV3.

I do not have any 1/4 to 3.5 mm adapters laying about but I am curious how do audio interfaces compare to dac around the same price point?

 

[III-V]

Yes I know the Toslink is not using the on board (analogue) audio.

The SPDIF signal is however still using the on board audio processing.

Of course ground loops can exist between the DAC and active speakers, but this is rarely an issue because most DACs are isolated from mains earth, and so long as they're not powered from the computers USB port they will effectively be floating.

A couple of years ago, I carried out a few tests to illustrate the effects of ground loops.

USB noise measurements

USB noise measurements, Raspberry Pi, Intel NUC, PC, USB DAC

gtkc.net

Interesting results. Later today I will have a usb adapter for my apple dongle so I will know if there is audible noise on the usb bus as well. If this solution works, I will likely keep it for a few months, but I am planning on investing into a balanced XLR dac (as to match my T5V's), possibly the SMSL M300SE as it was recommended and appears to satisfy all of my needs.

@III-V - My experience...

PC (USB) + Topping D50s DAC (RCA) +Topping A50s HP Amp (RCA) + Tannoy Reveal 402 = No Noise.
PC (USB) + Topping D50s DAC (RCA) +Topping A50s HP Amp (RCA) + iLoud MTM = Noise!

The difference between the Tannoy and the iLoud monitors is the the later has a 3 pin power connector with a safety ground (as do your TV5s).

So then I tried...

PC (USB) + cheap ADUM4160 USB isolator + Topping D50s DAC (RCA) +Topping A50s HP Amp (RCA) + iLoud MTM = no noise.
PC + Toslink bracket connected to SPDIF header (Optical) + Topping D50s DAC (RCA) +Topping A50s HP Amp (RCA) + iLoud MTM = no noise.

Both solutions above work, but both also limit the sample rate for some of my FLACs. Although this was definitely not audible to me, it nagged me a little and I also longed for a simpler solution than the Topping x50 stack and all it's wires and power supplies (I also have the P50 linear PSU). So, I bought a Topping EX5 DAC/HP Amp and relegated the x50 stack for armchair use.

PC (USB) + Topping EX5 (XLR/TRS) + iLoud MTM = No Noise!

Later, I added an in-line sub (which also has 3 pin power)...

PC (USB) + Topping EX5 (XLR/TRS) + Presonus Sub8 (TRS/TRS) + iLoud MTM = Still No Noise!

If you can move to a balanced solution, it's well worth it in the longer run. The EX5 was the perfect choice for me as it has a decent DAC, HP Amp, pre-amp functionality and it remembers HP and pre-amp volumes independently.

Another benefit of moving to a single box for DAC/HP Amp and Pre-amp duties is that I can do fun things like this: Controlling PEACE/eAPO on Windows with Topping DAC/Amp Remote (or any other IR remote)

Yes, my next large purchase will likely be either a dedicated dac or multipurpose dac but for certain I will make the switch to a balanced output and balanced cables.

Don't bother doing this, it didn't help in my situation. I even sanded off the paint at the screws!
View attachment 329752

I saw someone mention Kali. My IN-8 V2 had more hiss with RCA enabled+connected and the computer OFF, and this was connected to Topping DX3 Pro+. I got a powered interface with XLR, and they are very quiet that way.

I am very lucky that when the computer is asleep or off completely the monitors are silent while still powered on (or at least I can't hear any noise).

 

[JayGilb]

I do not have any 1/4 to 3.5 mm adapters laying about but I am curious how do audio interfaces compare to dac around the same price point?

Very comparable. An audio interface is generally an a->d/d->a converter with microphone level inputs.

 

[III-V]

Ok a quick update: adding in a USB to USB-C adapter to Apple dongle, I still have computer noise, although I estimate it has been reduced by as much as 10 dB, possibly more, so that is a win in my book for $7.

I will still shop for an external dac solution, although this and simply rolling the T5V amplifier gain down another 10 dB means that I can sit at the desk with the monitors on and not go crazy with the noise. Thanks for all of the suggestions and help everyone. I will possibly make a new thread just about the desktop dac and update this one again once this issue is resolved or if any other suggestions or comments are made.