What did you measure it with?
As to your question about soundcard manufacturers - of course they can do it. And no, its not particularly expensive. Do they see the need is the question. Are their customers asking for it? I think the answer to that is 'no' but more than happy to be enlightened.
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Dave, what you are saying is that you are not listening to the DAC you are listening to a combination of components - that is what I claimed jonks ago in this thread. So how do you define the best DAC in the world.
Well, the sound card in question was SY's Lynx, and seems to not suffer from any of the previously mentioned issues based on the Stereophile measurements.
I can't find a review of the 1820m using an AP with a quick search right now. I thought I had come across one before though. I've used ARTA with my own a few years ago and I can tell you I didn't have any 60 Hz at -114 dB though. That plot from exaSound looks like a ground loop to me. Bet it still sounds fine though 🙂.
I can't find a review of the 1820m using an AP with a quick search right now. I thought I had come across one before though. I've used ARTA with my own a few years ago and I can tell you I didn't have any 60 Hz at -114 dB though. That plot from exaSound looks like a ground loop to me. Bet it still sounds fine though 🙂.
Depends whether by DAC you mean the DAC chip or the DAC you can actually use in your hifi.
dave
My original comment was an "in general" and not specific to SY's Lynx 22.
An externally hosted image should be here but it was not working when we last tested it.
No special shielding and lots of PCB traces (ie antennas). Doesn't mean its not RF hardened.
dave
Dave
They forgot to place most of the components
- does it matter? Make it sound less terrible?🙄
They forgot to place most of the components
- does it matter? Make it sound less terrible?🙄
Sure its a ground loop - have you digested Bruno Putzeys article on grounds? The DAC's unbalanced outs cannot not have ground loops, by virtue of being unbalanced.
Bet it does indeed sound fine to you 🙂
Well, I'm not familiar with the product and didn't realize it was using unbalanced outputs. I don't use unbalanced inputs or outputs so on a "high end" device I naturally assumed the same.
Are you claiming you can hear what's in that spectrum at listenable levels? The worst of which was at -114 dB?
Are you claiming you can hear what's in that spectrum at listenable levels? The worst of which was at -114 dB?
No - the spectrum's ultrasonic and I'm not a bat. Oops, sorry misread the frequency scale. My bad 🙂
I doubt I'd hear it in the absence of any other signal, its audibility will depend on the intermodulation performance of the downstream kit.
The problematic stuff isn't the 60Hz and harmonics as they'll not generate much noise modulation - the broadband stuff above the audio band I reckon will likely lead to a reduction in perceived dynamics. This is just a guess based on experience with the effects of such common-mode noise.
I doubt I'd hear it in the absence of any other signal, its audibility will depend on the intermodulation performance of the downstream kit.
The problematic stuff isn't the 60Hz and harmonics as they'll not generate much noise modulation - the broadband stuff above the audio band I reckon will likely lead to a reduction in perceived dynamics. This is just a guess based on experience with the effects of such common-mode noise.
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60Hz is not ultrasonic last I checked and that's where the highest peak is.
Saw your edit, fair enough.
Saw your edit, fair enough.
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No, it isn't an issue, you can measure that it isn't issue, you can hear that it isn't an issue, the only thing left is to think about how those clever sound card engineers managed to keep the noise out.
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see that a number of posters already posted something similar, so it must be true!
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Yes exactly it's a ground loop. The measurement would be degraded similarly if the signal source was some premium CD player engineered for low noise. I too see similar deteriorations in measured performance without my galvanic isolator in place, but that's not because of a PC environment being noisy, it's because of the ground loop itself.
The PC's switching supply energizes the ground loop - which is why you see the broadband ultrasonic hash on the right of the plot. You'd not get such rubbish with a linear supply unless your mains was already corrupted by other noisy switchers in the vicinity.
Except with high speed switching designs current will only flow where it's been designed to flow. It will not go down the USB cable and it will not flow down the shield of the analogue cable, which is where the problem is coming from. The currents will be kept in well controlled and short tightly bound loops due to good high frequency design of the motherboard and its attached peripherals. Without these the PC would not work and even if things got a bit sloppy the return currents would still flow back to the SMPS inside the computer, they would not flow down the USB or phono cable. The last thing a high frequency return current wants to do is go down a long external type cable.
The point here is that you can easily design sound cards to work without suffering from any problems associated with being installed within a PC.
How do you know?
You can - well one can, one would need a better grasp of EMC than you've so far shown 😀
Dave
They forgot to place most of the components
Nah, It's to allow tubes for SY
!
If it does anything to the audio, that shows up in the audio band. If it doesn't show up in the audio band, there's nothing there to hear.
I wish!
I think this is true, but do you know the minimum requirement for the CPU for this to happen? I don't believe average CPU is "that" good. I have heard the effect of power supplies to DAC, so, what can I expect from cheap switching supply (powering all and every circuits)? I have very expensive switching supply with silver wires ( 😀 ) everywhere, but I have always been dissatisfied with switching supply.
I use Dell Optiplex BTW... because I think they are very quite. I have also toroid based CPU power supplies, but feeding LMxxx switching regulator chips (around 200MHz)...
I'm not a user of top quality DACs... so I think sound card or external DAC doesn't really matter... But for top result, I think internal sound card with average CPU cannot compete with asynchronous external DAC or even with Firewire/Ethernet DAC.