PC > 3 Channel Mixer > PC Recording [Will there be latency]?

[AkiraKrist]

Hi. I'm an experimental musician. I DJ, play guitar, and sing, simultaneously.
I'm trying to record PC audio, guitar, and vocals, all at once, without latency.

The reason is, because I DJ PC audio, while singing and playing guitar, &
I'd like to record these 3 audio sources as a single track, in audacity/OBS.

If I headphone-monitor the PC-audio-output from the mixer & there's latency,
then the guitar and vocals that I'm playing in synch to the PC audio I'm hearing,
won't be in synch when the 3 tracks are combined and output into 1 in the PC.

TLDR:
Is there a way for me to play pc audio from my pc,
and play guitar and sing along to that pc audio,
and then record all 3 on the same pc,
without having any latency breaking the synchronization of all 3 sources?

Would it help if I just monitored the PC audio using my PC's headphone jack,
then used OBS to record that PC audio directly,
while using OBS to record a 2 channel mixer with my vocals and guitar.
Would everything be in synch then, without sending + receiving PC audio?
Does sending that PC audio out into the mixer, and then back to the PC,
cause latency?

Thanks for reading, I hope someone understands my question.

[Hugh Robjohns]

Is there a way for me to play pc audio from my pc, and play guitar and sing along to that pc audio, and then record all 3 on the same pc,
without having any latency breaking the synchronization of all 3 sources?

Yes, of course. This is a standard requirement of DAWs... but the devil is in the detail.... particularly in how you're generating the DJ audio, what interface you're using, and whether you want discrete tracks in your DAW or a live mixed (stereo) track?

[AkiraKrist]

Is there a way for me to play pc audio from my pc, and play guitar and sing along to that pc audio, and then record all 3 on the same pc,
without having any latency breaking the synchronization of all 3 sources?

Yes, of course. This is a standard requirement of DAWs... but the devil is in the detail.... particularly in how you're generating the DJ audio, what interface you're using, and whether you want discrete tracks in your DAW or a live mixed (stereo) track?

I'm generating the DJ audio through Youtube tabs, 3 at once.
The external interface I intend on using is a 3 channel mixer (of any brand),
with 2 XLR inputs for my vocal mic and guitar mic,
and 1 USB or line in input for the DJ audio.
After mixing down the tracks into 1 track, id sent that to OBS or audacity,
as a single track.
SCENERIO 1:
If I monitor the audio directly from the PC,
so that I only hear the Youtube audio playback,
then would there be latency un-synching Youtube audio, from my XLR tracks,
by the time they are both mixed into 1 track through the mixer?
SCENERIO 2:
Otherwise, I could monitor the PC audio from the mixer instead,
but then I would hear my vocals and (acoustic) guitar playback alongside,
and it might be kind of jarring to be hearing my vocals and acoustic guitar,
within the headphones, and outside of the headphones simultaneously.
In this case, latency wouldn't matter, because the PC audio I'm playing to,
is only heard by the time it reaches the mixer, so my XLR tracks would be
in synch with the audio in my PC audio track.
SCENERIO 3:
Also, I could send the Youtube tabs directly to OBS/audacity,
using the "PC Mix" track on windows, which records all pc audio.
I would monitor the PC audio through headphones connected to the PC.
Then I would play and sing along to that audio, through the XLR tracks.
Then I could send my two XLR tracks to the PC through line out, or USB.
Would there be latency involved with the time it takes for my XLR tracks
to reach the OBS/audacity mix-down?
QUESTION:
Can you recommend a USB-out soundcard mixer with two XLR tracks,
with the lowest latency,
if the best choice is scenario 3,
or can you recommend a USB-out soundcard mixer with two XLR tracks,
and a 3rd line-in tracks, with the lowest latency,
if the best choice is scenario 1 or 2?

[ef37a]

The MOTU M4 and other interfaces now, have a 'loop through' facility whereby they can record any signal, YT, radio etc, running on the computer. Thus you can have that signal on inputs '5/6' and mic and guitar on 1 and 2 and that still leaves line inputs 3/4 for other purposes.

Since it all runs under the ASIO driver they must I think be locked together? Basic latency will depends as ever on the sample rate setting and how well behaved the computer is. In my experience, latency with MOTU drivers is not a problem.

Dave.

[Sam Spoons]

Your use of ODB suggests this is intended to be streamed as a live performance? If you simply want to record (for later broadcast?) then I would separate the DJ audio from the live guitar/vocal either by recording the YT audio onto separate tracks in a DAW instead of streaming them as you play/sing or by downloading the audio* by some means and dropping the files into the DAW. That way you have control over the sync of the parts and the ability to mix everything afterwards. I realise that this removes the spontaneity of the 'live performance' but it also removes most of the issues you are encountering.

* I am slightly concerned WRT the potential copyright issues when it comes to using YT audio in this way?

[ef37a]

"* I am slightly concerned WRT the potential copyright issues when it comes to using YT audio in this way?"

Good point Sam and this I think is the reason Msoft 'killed' loop through recording in Windows post Win 7 (never had an 8).
When I was trying to restore the function in W10 I was told that some MOBOs can be 'hacked' in BIOS to fix it. Not mine or at least not at any level I am comfortable with or indeed competent!

Dave.