PC audio through an external DAC

[barryadam]

I am new to the digital audio technology, so please bear with my dumb questions and assumptions.

For starters, I am referring to a system that outputs audio from my desktop PC to the AUX channel of a stereo system receiver.

It's my understanding that the integrated sound processor on a desktop PC may have a low quality DAC, and an external DAC can greatly improve the sound quality. That would apply to all PC audio sources, then, right?

My PC has no digital audio output. External DAC units, such as the Schiit units, have USB connections for input from the computer.

So my question is, how do the digital audio files get output to the USB/DAC, bypassing the integrated sound card, and associated drivers for Windows?

I see discussions about how people are using external DACs on a PC or laptop for Hi-Def Streaming Audio sources, but I am not clear on the details of how that works differently than regular audio from my PC, like Soundcloud, Spotify, YouTube, or anything else played on the PC, as far as a user interface, or to direct the digital output to USB and not the integrated sound processor.

Barry

 

[benricci]

If you are using a modern external DAC with a PC, and it has USB inputs (like a Schiit DAC, for example), it's incredibly simple.

STEP 1. Plug a USB cable going out from your computer into the DAC. Depending on your computer, you may or may not need to select the new DAC as your audio output device in your system settings. My MacBook recognized it automatically, but your mileage may vary. As far as "setup" goes, you're pretty much done after that. All audio from your computer will now be sent to the DAC over USB, bypassing your computer's internal sound card (DAC).

STEP 2. Plug analog RCA outputs from the DAC to your receiver. The DAC is now in charge of converting all that digital audio being played on your computer to an analog signal your stereo receiver can handle through any available AUX input.

STEP 3. Enjoy listening to audio from your PC through your new DAC! Pretty much any modern, well-made DAC will recognize all hi-res audio formats coming from your PC and adjust to sample rates on-the-fly so there's really nothing more to do.

 

[swechsler]

Typically, when you connect a new audio device to your PC, it is automatically detected and picked as the primary output. You can change it by right-clicking on the speaker icon in the taskbar and choosing "Sound settings". Once you change the primary output, all apps that send their sound to that output will automatically switch.

Some apps allow you to select the audio output independent of the system's primary output. Those will need to be changed manually.

 

[barryadam]

Thanks.

"...select the new DAC as your audio output device in your system settings. .... All audio from your computer will now be sent to the DAC over USB, bypassing your computer's internal sound card (DAC)."

That's the part that is confusing to me. Right now, I can select the audio output to go to my headset (for Zoom calls), or to the Realtek/speakers. I assume that no matter what I choose, it is output from the integrated sound processor that goes to this device.. These output device choices are just analog recipients of the output of the sound processor.

So you are saying that the selection of the external DAC as output would then somehow also direct the PC to send all audio files in digital format to the external DAC, and not through the integrated sound processor?

OK then, I shall proceed accordingly.

Thanks again for clarifying that detail.

Barry

 

[barryadam]

Typically, when you connect a new audio device to your PC, it is automatically detected and picked as the primary output. You can change it by right-clicking on the speaker icon in the taskbar and choosing "Sound settings". Once you change the primary output, all apps that send their sound to that output will automatically switch.

Some apps allow you to select the audio output independent of the system's primary output. Those will need to be changed manually.

Got it. Thanks.
I guess this was more of a PC question than an audio one.

Barry

 

[swechsler]

Right now, I can select the audio output to go to my headset (for Zoom calls), or to the Realtek/speakers. I assume that no matter what I choose, it is output from the integrated sound processor that goes to this device.. These output device choices are just analog recipients of the output of the sound processor.

If you have a Bluetooth headset, then the DAC is within the headset. If it's connected to the headphone jacks on the computer then you're using the integrated DAC.

 

[Yamaki]

Any digital output from the PC will not be processed by the internal PC sound card.

So if you connect a USB A to B cable to the PC USB output, then connect the other connector into the DAC's USB B input, you will have a digital signal that can be processed by the DAC.

USB A to B cable:



DAC USB B connection:

 

[benricci]

That's the part that is confusing to me. Right now, I can select the audio output to go to my headset (for Zoom calls), or to the Realtek/speakers. I assume that no matter what I choose, it is output from the integrated sound processor that goes to this device.. These output device choices are just analog recipients of the output of the sound processor.

That is correct -- but I'd recommend you replace the phrase "integrated sound processor" with the term "DAC" (digital-to-analog convertor). It'll help simplify things.

Right now, there's a DAC (what you refer to as an integrated sound processor) inside your computer.

All the audio your PC processes during the course of a day is digital, which your ears cannot do anything with (obviously). So your computer's DAC converts those digital signals (whether it's a YouTube video, a Spotify stream, or a Zoom call) into an analog signal that can then be sent to headphones, to an aux output on your computer (which can feed a stereo receiver, etc), to the computer's built-in speakers or any other location depending on what types of audio outputs your PC has.

From there it's amplified as sound you can actually hear. I've simplified the process greatly to help illustrate a point, but that's pretty easy to grasp, right?

All an external DAC does (say, a USB-enabled Schitt model, for example) is MOVE that process OUT of the computer and handles it in an external box, which should, presumably, sound better than whatever DAC your PC shipped with. It'll likely be able to handle higher-resolution audio, too, depending on how old your computer is. But since I don't know what you've got currently, that's just a broad generalization.

In any event, all you are doing is taking a process that would normally happen inside your PC (converting digital audio information to analog audio signals) and moves it outside the PC.

Some people find it to be a great benefit, and others are fine with the quality of the audio already coming from their computer, and don't see the need for an external DAC. Or, they're not streaming hi-res audio or doing much music listening in the first place and don't require one at all.

Everyone's situation is different.

 

[Rockyhill]

Any digital output from the PC will not be processed by the internal PC sound card.

So if you connect a USB A to B cable to the PC USB output, then connect the other connector into the DAC's USB B input, you will have a digital signal that can be processed by the DAC.

USB A to B cable:

View attachment 2833863

DAC USB B connection:

View attachment 2833868

Depending on the DAC (like Schiit Modi) , it might accept a USB micro B plug.

 

[cpt_paranoia]

It's my understanding that the integrated sound processor on a desktop PC may have a low quality DAC

One other aspect of PC audio is the path the digital signal takes through the audio subsystem; this may be the 'integrated sound processing' you are talking about. Windows includes audio mixing, and various processing effects. You may want to disable those, to get bit-true delivery to the DAC. You can do this by selecting 'WASAPI exclusive mode' in the audio driver settings.

 

[barryadam]

If you have a Bluetooth headset, then the DAC is within the headset. If it's connected to the headphone jacks on the computer then you're using the integrated DAC.

Thanks. Headsets are wired.

Any digital output from the PC will not be processed by the internal PC sound card.

So if you connect a USB A to B cable to the PC USB output, then connect the other connector into the DAC's USB B input, you will have a digital signal that can be processed by the DAC.

USB A to B cable:

View attachment 2833863

DAC USB B connection:

View attachment 2833868

Thanks

That is correct -- but I'd recommend you replace the phrase "integrated sound processor" with the term "DAC" (digital-to-analog convertor). It'll help simplify things.

Right now, there's a DAC (what you refer to as an integrated sound processor) inside your computer.

All the audio your PC processes during the course of a day is digital, which your ears cannot do anything with (obviously). So your computer's DAC converts those digital signals (whether it's a YouTube video, a Spotify stream, or a Zoom call) into an analog signal that can then be sent to headphones, to an aux output on your computer (which can feed a stereo receiver, etc), to the computer's built-in speakers or any other location depending on what types of audio outputs your PC has.

From there it's amplified as sound you can actually hear. I've simplified the process greatly to help illustrate a point, but that's pretty easy to grasp, right?

All an external DAC does (say, a USB-enabled Schitt model, for example) is MOVE that process OUT of the computer and handles it in an external box, which should, presumably, sound better than whatever DAC your PC shipped with. It'll likely be able to handle higher-resolution audio, too, depending on how old your computer is. But since I don't know what you've got currently, that's just a broad generalization.

In any event, all you are doing is taking a process that would normally happen inside your PC (converting digital audio information to analog audio signals) and moves it outside the PC.

Some people find it to be a great benefit, and others are fine with the quality of the audio already coming from their computer, and don't see the need for an external DAC. Or, they're not streaming hi-res audio or doing much music listening in the first place and don't require one at all.

Everyone's situation is different.

Understood.
My misconception was that the PC's output selection (headphones, speakers, etc.) was, in effect, switching the output AFTER the integrated DAC only. Thanks for confirming it can also switch that processing to the external DAC.

Depending on the DAC (like Schiit Modi) , it might accept a USB micro B plug.

Thanks.

I understand now.
Thanks to all that replied.

Barry

 

[barryadam]

One other aspect of PC audio is the path the digital signal takes through the audio subsystem; this may be the 'integrated sound processing' you are talking about. Windows includes audio mixing, and various processing effects. You may want to disable those, to get bit-true delivery to the DAC. You can do this by selecting 'WASAPI exclusive mode' in the audio driver settings.

Thanks.
If/when I get a DAC, I will look for that.

Barry

 

[E-Stat]

Even phone or pad devices can connect to external USB DACs and avoid lots of overhead found using a general purpose PC. The lightning connector on an iPhone or iPad contains a digital output and can be accessed using a simple adapter Apple calls the “Camera Adapter” that includes a USB B jack.

 

[slow_jazz]

Most usb sound cards have digital outputs.

I use a usb Soundblaster feeding my dac.

 

[DiggyGun]

I use the Khalsa ToneBoard DAC. This uses a standard USB cable from the PC to a USB C to the DAC. It then has stereo RCA plugs to go to your system.



No additional power cable is required as it also takes power via the USB.

I’ve tried a few external DACs and found this one to be the best and for the money it is also very good value.

DG…

 

[lini]

(...) Headsets are wired. (...)

Then it would still depend on the type. Because a wired headset could be a conventional, analogue type (with older ones usually sporting two separate miniT(R)S plugs (one for the headphone/earphone output, the other for the microphone input) - while newer ones typically sport a miniTRRS plug (with either OMTP (second ring = Aux/Mic, sleeve = combined ground) or CTIA (sleeve = Aux/Mic, second ring = combined ground) contact assignment; nowadays usually the latter)) - but it might as well also be a USB headset.

In the former case the headset would obviously require some sort of computer sound hardware (be that "onboard sound", a dedicated sound card or an external sound interface) to work with.

Whereas a USB headset would represent a somewhat specialised sort of USB sound interface (most usually USB audio class 1 compliant, so that a separate driver isn't required, as pretty much any modern operating system already comes with a standard driver for such devices (*)) and USB HID (= human interface device; for extras like volume control and mute buttons...) itself - typically implemented in form of a highly integrated USB audio codec chip (like for example the Cmedia HS-100C), which already contains most of what's required for the purpose (USB transceiver, DAC with earphone driver(s), ADC with microphone input...), so that not many extra parts are needed and such a USB headset can be not much more expensive than a conventional, analogue headset.

Greetings from Munich!

Manfred / lini

*) In fact, more recent operating systems will typically also already sport a standard driver for USB audio class 2 devices, but the extended capabilities of USB audio class 2 aren't really needed for a typical USB headset.