[miketlse]

@Amberlamps grab some too.

 

[gnomen]

I blush to say it - so munch on your popcorn - but I don’t buy a DAVE because I prefer the styling of the TT2. I hope the next iteration of design, whenever it arrives, is less 70s Star Trek and more compatible with the MScaler house style.

 

[AndrewOld]

I guess you know the answer because Rob has spelled it out many times and hence why I don’t need to suppose. It travels in the ground plane and hence why he uses his laptop in battery mode rather than with the mains charger plugged in.

@Rob Watts please tell me if I should eat humble pie and admit I am wrong in what I just said.

RF cannot travel through optical fiber. There is no ground in an optical fiber. It does not connect the grounds at either end. Or make any electrical connection. There is however a ground in USB and RCA s/pdif, so they can both form a ground loop if the equipment at both ends is connected to earth. I think Rob uses USB and therefore likes to run his laptop from batteries so the laptop isn’t earthed or connected to neutral.

Surely someone who sells £1400 cables should have a clue about how cables work.

 

[organicmac]

RF cannot travel through optical fiber. There is no ground in an optical fiber. It does not connect the grounds at either end. Or make any electrical connection. There is however a ground in USB and RCA s/pdif, so they can both form a ground loop if the equipment at both ends is connected to earth. I think Rob uses USB and therefore likes to run his laptop from batteries so the laptop isn’t earthed or connected to neutral.

Surely someone who sells £1400 cables should have a clue about how cables work.

Oh not again please.......................

 

[Currawong]

Oh not again please.......................

I've got to admit, when I read about ground noise over an optical fibre I had to double-check nobody had spiked my coffee with drugs.

 

[118900]

deleted

 

[Amberlamps]

@Amberlamps grab some too.

I shall grab some, merely because its 3am and I’m fking starving, as I was asleep all day.

 

[Rob Watts]

I guess you know the answer because Rob has spelled it out many times and hence why I don’t need to suppose. It travels in the ground plane and hence why he uses his laptop in battery mode rather than with the mains charger plugged in.

@Rob Watts please tell me if I should eat humble pie and admit I am wrong in what I just said.

Yes but that was with USB connection. Optical can't create ground plane noise from the source ground. However, in principal it could inject a small amount of ground currents into the ground plane from the amplifier built into the optical receiver device. But this is ultra small scale stuff; but I do put ferrite beads and RF filters on the optical receiver just in case it might have an effect. But noise from the source will be eliminated with optical, as the noise from the optical amplifier in the receiver would be SPDIF only related noise. You still have the possibility that the source will inject processing related noise into ground and the mains, and then being picked up inside the DAC from ground loops, but again this is very much a theoretical possibility - it needs intersecting ground loops to create an effect so that the DAC will "see" the noise - and this is certainly not an issue if the DAC has optical inputs only, and no other ground connections on the analogue side (listening only via headphones directly for example).

If you suspect issues with your source, then just use your mobile phone with bit perfect app - you can use USB - as the phone is isolated from ground, so you can't get any ground plane noise from this. If your source sounds identical, or close to identical, then don't worry about the source from a SQ POV.

 

[flyte3333]

I guess you know the answer because Rob has spelled it out many times and hence why I don’t need to suppose. It travels in the ground plane and hence why he uses his laptop in battery mode rather than with the mains charger plugged in.

@Rob Watts please tell me if I should eat humble pie and admit I am wrong in what I just said.

Optical is... light.... Ground currents don't normally travel via light...

 

[CaptainFantastic]

Optical is... light.... Ground currents don't normally travel via light...

My knowledge on this is very limited, but here is what I discovered last week by chance.

My system has two optical outs. Optical 1 out is from my high-end Asus ROG Strix Z490-H motherboard. Optical 2 is from my Asus Essence STX II.

I have the same high-quality (QED Reference) optical cable running from both, one to the TT2 and the other to the RME ADI-2. I mean, the one to the TT2 runs to the HMS, but for the experiment below I connected directly to the TT2 and ensured it's not the HMS creating the effect.

Optical 1: dead quiet when listening and also when sound paused. But after stopping/muting any audio signal on my PC, if I turn the TT2 volume wheel toward max white, there is a hssing noise for about 8 seconds and then it goes back to pitch black. Again, this is only at the highest and near-highest volume setting, so not a realistic real world scenario, but interesting to note.

Optical 2: dead quiet when listening and also when sound paused. After stopping/muting any audit signal on my PC, still dead quiet at max volume.

So what could be causing the Optical 1 which is directly from the motherboard to exhibit that hissing noise at max volume and Optical 2 not to?

I would rather use the Optical 1, because for Optical 2 I have to use a mini-Toslink to Toslink adapter which is probably not the best thing to introduce (even if AudioQuest) with the high-quality cable I am using.

 

[flyte3333]

So what could be causing the Optical 1 which is directly from the motherboard to exhibit that hissing noise at max volume and Optical 2 not to?

Not ground currents...

The assumption in these discussions is properly functioning TOSlink sources.

Hard to know why the motherboard TOSlink output behaves like this.

 

[kennyb123]

Depends how you interpret that conclusion?

You know people buy and then sell Dave for the same reason?

I don’t know what you are asking.

It was fortuitous that Rob posted just before me and wrote: “The problems with measurements are numerous. What are you measuring and how does this correlate with sound quality is one major issue.” I think it’s a mistake to think that just because a DAC measures the best that it sounds the best.

 

[AndrewOld]

What’s up @Triode User? You’re a bit quiet! Humble pie stuck in your throat?

 

[118900]

deleted

 

[feddar]

... I do put ferrite beads and RF filters on the optical receiver just in case it might have an effect...

Nice to know, yet again, we can always count on you to do the right thing. Thanks!

... You still have the possibility that the source will inject processing related noise into ground and the mains, and then being picked up inside the DAC from ground loops, but again this is very much a theoretical possibility - it needs intersecting ground loops to create an effect so that the DAC will "see" the noise - and this is certainly not an issue if the DAC has optical inputs only, and no other ground connections on the analogue side (listening only via headphones directly for example).

So, are you saying that if the DAC (the HMS/TT2 combo in my case) is only using the optical inputs (despite having the other inputs available), and you are only using headphones, then even this theoretical possibility is null?