The goal of mixing for a live stream isn't that people notice how great your mix is, but that they don't notice your mix at all.
Once people figure out the video and internet portions of the live stream, there is nearly always a problem that comes up. What sounds good in-person often sounds horrible online, especially music.
So, how do you overcome this issue? There's actually a lot you can do.
First, you need to realize what some of the ingredients to a pleasant sounding mix are.
Add in reverb
If you've ever been to a party with karaoke, you probably noticed something about what they do to make marginal singers sound better. Reverb. If you merely amplify the sound, but the audience doesn't hear it in a space that has enough presence, any mistake is amplified, too. Sure, great singers may not need help, but there's something about adding in a little reverb that helps hide minor mistakes.
In person, depending on how your room is built and treated acoustically, you might have natural reverb that adds to the sound.
Add an ambient mic
Some have found that when doing a live stream from a phone, the audio from singers might sound less intelligible, but also better. That's because the phone microphone picks up ambience from the room. So, in addition to adding a little reverb, you might also add an ambient mic to mimic the sound of the in-person audio for the online congregation.
In fact, adding in a little ambience can go a long way to fix what ails a mix which might seem dry without it.
That said, you should probably never send the same audio that goes to the PA to the live stream. They're just different. If you have, for example, acoustic drums, in person, they're probably so loud that you have to take measures to dampen them, like putting them in a cage or behind a plexiglass barrier.
You should probably never send the same audio that goes to the PA to the live stream. They're just different.
Online, though, you wouldn't have any natural sound from them UNLESS they're mic'd and mixed into the rest of the sound.
As a result, the mix for the live stream shouldn't be mixed based on what the sound engineer thinks it should sound like, looking at meters and making a guess. It's better to know based on mixing with good sound isolating (not cancelling) headphones or, even better, what it sounds like in an acoustically isolated space.
Use your mixing tools
With the Behringer X32 and other digital mixing desks, you now have an option to try out an isolated mix. If you doubt that an engineer could positively affect the sound by creating a mix that's unaffected by the mix made for the live environment, try this. Have an audio engineer download the remote app for your mixing desk and run the video with embedded audio over SDI to a separate room and convert it back to HDMI connected to a TV.
Now, make sure the mix your engineer hears is an aux send. Have them remix based on what they need to get better sound.
If your church isn't meeting in person currently, maybe just have your engineer mix for the live stream or recording with the PA off altogether. Sure, it will sound horrible in the sanctuary, but it should sound great in headphones and online.
There are a couple of things they'll probably notice immediately.
Consider dynamics
First, typically, music is louder than speaking. So people online would be tempted to turn up the live stream during speaking or turn down the audio during worship. On the face of it, that might not seem like a big deal, but it is a big deal when you change from one to the other. In that case, someone watching online might miss the first few words of the message or worse yet blow their ears out when a song starts.
Part of your goal here is that people aren't distracted by changes in dynamics.
This might mean that for the purposes of the live stream, your engineer would turn down the music and turn up the speaking so they're much closer to one another. Another strategy would be to apply a compressor on the output of the mixing desk that goes to the live-stream which would even out the differences from the loud and quiet parts of not only the music and speaking in general, but also within those elements.
Your goal is that the pastor can whisper or yell for dramatic effect without people online losing what's said (or their hearing) AND for quiet passages in songs to be clearly audible so that no nuance is missing.
Perhaps with orchestral music, dynamics are a huge part of the live performance, but keep in mind that a large portion of your online congregation will be listening on tiny little speakers on devices like laptops, phones, and even with earbuds.
Adjust EQ
With that in mind, perhaps you'll want to tweak the EQ, too.
In person, low bass helps you feel like you're a part of the music. It draws you in.
Online, most people won't be watching with dedicated subwoofers that will vibrate their chests the way that your subs do in person. Since these lower notes aren't heard as much as felt, maybe you'd want to avoid sending them online.
Likewise, the highest end of the audio spectrum might do nothing for people watching online. So, maybe you'll experiment with eliminating them too.
Then there's resonance. Every room resonates with different frequencies, so some just seem naturally louder than others. The EQ that has been set for your PA probably takes this into account. As such, just like some instruments are very loud in person, so you don't add a lot of them into the mix for sound reinforcement, so certain frequencies are probably louder in person, so you turn them down in the mix.
So a single instrument or voice that's been EQ'd for your sanctuary might not sound exactly right, all things being equal, even if there is enough of it in the mix.
What you send to the live stream wouldn't have that problem, though. So a single instrument or voice that's been EQ'd for your sanctuary might not sound exactly right, all things being equal, even if there is enough of it in the mix.
Another, related issue that live sound engineers have to fight, and that those who mix for recording or live streaming don't, is feedback.
Perhaps one of the background singers isn't loud enough and, try as you might, you just can't turn them up enough because of feedback. With the audio for the live stream, you won't have to worry about feedback so it might be the case that once you tweak their EQ for the live stream and turn them up gain, you actually get a better mix than you do in person.
Ideally, this is all done by a dedicated person in an acoustically isolated space, but this might not be possible for every church. So, start by adding in an ambient mic. As a second step, have someone mix with headphones, or at least check periodically for glaring mistakes, and finally, progress to a dedicated engineer as a final step.
The goal of mixing for a live stream isn't that people notice how great your mix is, but that they don't notice your mix at all. Sure, sound people who are off for the week might, but the average person should never think "this doesn't sound as good." Like a lot of what we do, when we do it well, we're often not noticed at all and that's a good thing.
