Apologies if this has been covered elsewhere but I've been unable to find a definitive answer so I'll post it out.

Running v18, pretty standard setup, 3xSD cameras and a laptop coming in via Osprey 440 capture card with audio being fed in from a Presonus digital mixer (plus various video clips etc already in the computer) all back out to a data projector and also recorded. We have a separate audio card in the form of a Echo Mia MIDI - straight stereo in from the mixer and a stereo out to the mixer.

Yes, there is a noticeable lag between the on-stage action and the data projector but that will be addressed when the cameras and capture card go fully digital and we get rid of the A-D latency but in the meantime, I'm wondering about the audio and overall processor load.

What do people recommend, use the standard high definition onboard audio of the motherboard or a separate sound card?

Thanks in advance.

Warren

The Presonus is a 16.4.2 (one of the first models) and it has two Firewire ports. So if I added a Firewire card to the vMix computer I could in theory both send and receive the relevant audio via Firewire keeping it in the digital domain. Mind you, the latency on the Presonus is only around 4-5ms so it's not a big issue. You do raise an interesting point, SportsNet and I will explore that but my post was more about what most people have found to be more effective, especially with vMix CPU load.

I'm only interested in recording the mixer's stereo output to vMix as I have another PC running the Presonus software which records every track individually. I typically use 10-12 audio sources into the Presonus.

As far as I am aware you will always see a delay on audio coming out of vmix. This has been designed so that it matches the inherent video delay, typically 4 frames or so. You can adjust this in the audio setting of each input however up to -1000 milliseconds which I assume passes the audio direct from the soundcard. SportsNet is right about the different sources. It doesn't seem to make much difference. I've used the sound card, USB interfaces, and brought audio in through the camera. All work fine.

Remember if you are also projecting the vision, there will still be a delay on that vision which is why a lot of the staging companies will use a hardware switcher to feed the venue and tools such as vMix to overlay graphics and serve other content.

In the early days of PAL D colour TVs the cheapest way to delay the video one line was to send it
through a glass delay line and now we are plagued by delays that we don't want - for free.

I've never been keen about on board audio with its unbalanced lines in a digitally noisy environment.
My Blackmagic video cards sound so much better than the `HD' on board audio.

The Behringer usb interfaces are excellent alternatives but embedded sdi digital audio is my preferred option from the camera.

Oh boy do I have the perfect match audio wise for vmix......I will explain when the software is out of beta ,software audio live mixing with plugins and automation,and snapshots

We started out with onboard sound via the realtek soundcard. One time we had a gig on a metal boat with a generator. The boat transferred a huge buzz towards the cables, and we had no way to fix it!

It's this gig that learned us the importance of balanced audio cables (XLR) and professional soundcards.

After this, we also learned the hard way the importance of physical controls for sound: if an input is clipping, you really want to have good visual representation of it and a gentle way to control it.

Right now we use:

2 DI boxes which sit in between the source (PA system) and our XLR cables. Some XLR cables to microphones (shotguns). All of this comes into a small Yamaha mixer and goes via the output into a soundcard.

The mixer allows us to have physical control over our sources and to use pads and EQ to control the sound better. The mixer has several busses, so we can send out 6 channels seperatly into the soundcard.

In case of troubles with the external soundcard, we can always use the mixer via usb as a soundcard (only 2 channels though) or in case of emergency we always have the internal soundcard as a backup. We can also use the soundcard as a mixer (not as handy, but it works). The inputs of our capture cards (via the cameras) are the last fall back option. Having several options is always nice, we didn't have to use them a lot, but when we did, it saved our production!


I'd say: internal soundcards are totally ok for use in a studio, but really not suitable for a 'mobile' setup, because you never know where you're going to end up.

It does have audio inputs - via a breakout cable with RCA connectors on it. Unfortunately, I don't have the cable. I could get one I know, but as I also have a separate audio card, I decided to use that. The original reason for my question was related to reducing the processor load as much as possible and my thinking was that if I use a dedicated sound card, it doesn't impose additional processor load on either the CPU or the video capture card. Of course, running the audio through the video card would introduce a whole other set of fiddling about with latency correction and audio delay etc...