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Would SPDIF Optical Out from my motherboard's ALC892 be exactly the same as through my soundcard's?

companyja

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Hey guys, first post here, sorry if I'm posting in the wrong section,

I recently got a Fiio K5 Pro, I wanted a capable dac/amp mostly for future upgrades but it does drive my AKG K240 perfectly, I'm very happy with it. However, when used with USB, whenever my PC does something intensive like gaming, it has excessive crackling/popping which I imagine would be USB buffer overflow. I can't seem to avoid it using any port, my lone 3.1 port seems least affected but even that gets horrible to listen to in games.

So until I replace my motherboard which shouldn't be anytime soon, I decided to try and use optical in which should be the same really, maybe + some occasional jitter. Now my question is, does the source of the optical signal matter at all? I already put my old Creative X-Fi Titanium in another PC and I wonder if there would be any use at all bringing it back, installing it and routing through that instead of the onboard audio. Luckily my motherboard has SPDIF out, within realtek's HD codec whatever in windows. I imagine it bypasses the onboard DAC and amp altogether, but will realtek mess with the signal in any way? In other words, does it just pass the already resampled WDM signal, or does it do some resampling of its own? I know the creative x-fi titanium has something called "bit-matched output" which just really disables all the effects and EQ and doesn't let you control anything other than the volume, so I'd be a bit more comfortable routing it through that IF it mattered at all. Oh and just to be sure, I tested the headphone out of the motherboard and it's clean of electrical interference, just doesn't go loud and colors the sound quite a bit, I suspect the output impedance is rather high.

Cheers mates!
 
I decided to try and use optical in which should be the same

I don't notice any audible difference attributable to the little red LED among my various optical transmitters...

Measurements don't differ either, where applicable.

CD player, TV, HDRadio, PC, DEQ2496, miniDSP OpenDRC-DI, Focusrite Clarett 4 Pre, Cable Box, Oppo 93, Audio Authority 1177A switch, Topping D10, more?
 
Right, awesome, thanks mate. I'm just primarily wondering if the onboard audio affects the digital signal in any way before sending. I'm guessing that's a firm no, then
 
Right, awesome, thanks mate. I'm just primarily wondering if the onboard audio affects the digital signal in any way before sending. I'm guessing that's a firm no, then

Does Windows mess with the audio data? Yes, or no, depending on whether it is mixed or combined or exclusive or whatever. If it is "messed with" I suspect the mess is the same on USB or S/PDIF.

USB and S/PDIF use different encoding on the cable/coax/fiber, so, yes, the digital signal is "changed", but the decoded content should be the same.

Just do it, if you have a problem, then worry.

Right now anything coming from my PC goes out USB and gets converted to Optical to go across the room.

It's not a problem here.
 
Just make sure in your Realtek digital output that all effects are disabled, to bypass any signal processing, and shift the volume to 100% to avoid Windows’ mixer. The sampling rate and bit depth will be the ones that you select in the Windows driver output properties. If you want to make sure that Windows doesn’t mess with the source original one, they should match.

I use Voicemeeter Banana and then I can select a system wide output API (WASAPI exclusive, KS, ASIO). Foobar2000 and other players can do that as well (non-system wide).

While you’re at it, try Equalizer APO (if you haven’t yet) to correct room/headphones.
 
I've had the same issue when I try to connect a DAC on USB (and then Fiio K5 -> headphones): at very high levels I can hear noises related with video activity when doing some heavy 3D tasks like gamming. Tried various DACs, various ports (including special one designed as DAC-UP2 specially isolated for feeding DACs). The only solution that totally gets rid of all that digital noise is going optical out from motherboard (realtek 1220 -> Cambdrige Audio DacMagic - > FiiO k5 -> headphones). Zero digital noise, in fact zero noise at max volume in Philips SHP9500 (one of the most sensitive headphones I have here). So optical it is, zero interest in USB from now on. Don't hold your breathe anything will change by changing your MB.
 
Just make sure in your Realtek digital output that all effects are disabled, to bypass any signal processing, and shift the volume to 100% to avoid Windows’ mixer. The sampling rate and bit depth will be the ones that you select in the Windows driver output properties. If you want to make sure that Windows doesn’t mess with the source original one, they should match.

I use Voicemeeter Banana and then I can select a system wide output API (WASAPI exclusive, KS, ASIO). Foobar2000 and other players can do that as well (non-system wide).

While you’re at it, try Equalizer APO (if you haven’t yet) to correct room/headphones.

Note that selecting "disable all effects" (depending on driver you may or may not have this setting) also disables EqualizerAPO
 
There are several possible fixes for this problem (crackling, not electrical noise), I understand that you have already installed Fiio drivers for the device, if not do it, then depending on your motherboard and CPU brand there are different things that can be tried.

For example in my case with an AM4 MSI motherboard the fix was to force PCI-e speed to version 3.0 (not auto), and making sure that HPET was not forced by default, it can be checked by typing from the command line :

bcdedit /enum

search for useplatformclock, it should read no, or just not appear. Depending on the platform enabling it may be beneficial, but normally not for modern computers.
 
There are several possible fixes for this problem (crackling, not electrical noise), I understand that you have already installed Fiio drivers for the device, if not do it, then depending on your motherboard and CPU brand there are different things that can be tried.

For example in my case with an AM4 MSI motherboard the fix was to force PCI-e speed to version 3.0 (not auto), and making sure that HPET was not forced by default, it can be checked by typing from the command line :

bcdedit /enum

search for useplatformclock, it should read no, or just not appear. Depending on the platform enabling it may be beneficial, but normally not for modern computers.

Yes, I have installed them, changing the buffer in the fiio control panel has absolutely no effect, I tried uninstalling it and using Microsoft's driver just to be sure (amusingly, Microsoft correctly identifies it as Fiio K5 Pro: Fiio's OWN driver just says Fiio Q Series - this is the weirdest laziness I've seen). No changes there, too.

I tried messing with turning off individual USB ports on the same hub, turning USB power management in windows off, turning USB 3.1 charging off, enabling and disabling legacy (non-EFI) USB drivers, none of it helped. But I have not yet tried what you've suggested, I guess I'll give it a shot. If optical works and doesn't change the sound whatsover, it would be ideal since I wouldn't have to even worry about USB ports ever again! I just need to buy me a cable tomorrow, nice and short, 1-1.5m will do.
 
Many earlier Ryzen boards do have high DPC latency...

There's no easy way out of this. You can go into device manager and disable as many things that you think you don't need - Unused audio controllers, network devices...

Or just stick to onboard / soundcard.
 
I'm on an ASUS Z170-A, so skylake. It's disappointing because it's otherwise a fantastic motherboard. If spdif is the same stream as USB I don't see the big reason for frantically troubleshooting this, just gotta get tjat cable.

On an interesting note, my Fiio X3 III which I've used via USB sparingly shows no such problems; could it be that it being asynchronous, it avoids this issue? Is the k5 pro asynchronous, too? Not too sure what asyncrhonous USB transfer really does...
 
Well, I bought an optical cable, hooked it up to the onboard SPDIF and it works great! I'm not going to obsess over the sound quality, it sounds the same and I trust that it is exactly the same as USB or as it would be through the SPDIF out of my soundcard, anyway. I don't even bother doing WASAPI or ASIO exclusive mode and I just let windows resample to 24/48, so it's not like I'm going for ultra pure signal, anyway. Cheers mates
 
I have a motherboard with ALC892 with optical out and an X-Fi Titanium HD with optical in. In my own test my X-Fi is capable of recording bit-exact output from ALC892 with WASAPI exclusive mode, as shown in this post:

https://www.audiosciencereview.com/...bout-quality-of-software-volume-control.5922/

However, keep in mind that I was using Windows' built-in driver without using any additional driver or software from Realtek, so I don't know if the Realtek driver would affect the results or not.

I tested the headphone out of the motherboard and it's clean of electrical interference, just doesn't go loud and colors the sound quite a bit, I suspect the output impedance is rather high.
Many motherboards output less than 2Vrms, so they are naturally quieter, like this one:
https://www.audiosciencereview.com/...ernal-dac-headphone-amplifier.4116/post-96588
 
Nice, I guess I can have peace of mind of sorts, then, no need to drag my old soundcard back if the SPDIF out from the realtek doesn't color the sound. Yeah I tried not using the drivers but I didn't have windows update driver downloading disabled and it just grabbed the realtek drivers anyway, I said oh well, I get Realtek's ASIO this way which I guess is kind of cool if not all that different from asio4all. I just disable the realtek control panel so that I don't have to deal with that mid 2000s disasterious interface and disable all enhancements in windows, I imagine this completely ignores whatever DSP the realtek chip is trying to do, anyway.

I tested Realtek's ASIO in foobar2000, it does indeed send the required bitrate as indicated by the color of the k5 pro's LED (yellow for >48khz, blue for 44.1-48khz). I'm very happy with this, even after just two days it was torture to constantly hear crackling as if I bought a 90s ripoff soundblaster or something. Maybe I'll try USB again if I change to a new ryzen build in the future. Cheers mates!
 
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