Can I Record IPhone Video with Laptop Audio?
June 5, 2022 12:32 PM   Subscribe

I’m creating music on my laptop and also recording video on my iPhone at the same time. I want the video to include the audio directly from my laptop (to get rid of any background noise), but I also need to be able to hear the music in real time through headphones. My attempts so far (explained below the fold) have failed. Is this course of action possible and if so, what equipment/software do I need to accomplish this?

I used this tutorial , purchased the suggested equipment (with a lightning adapter to 3.5mm adapter, since I have an iPhone 11) and I set up Loopback to create a virtual monitor so I could hear the computer audio via my AirPods. This set up did not work, the recorded video used my phone’s mic instead of computer audio.

I have a physical sound card (Focusrite Scarlet 2i4) that I can use if needed. My experience is limited, so any guidance is greatly appreciated!
posted by chara to Technology (8 answers total)
Is there a reason you can’t just add the audio track to the video in software afterwards? This would give you the best audio quality.
posted by doctord at 12:52 PM on June 5, 2022

You're never going to hear audio in real time through AirPods, because like every BlueTooth audio device they have a distractingly perceptible amount of latency.

In your shoes I'd be doing my real-time monitoring with wired earbuds plugged directly into the laptop. I'd also make no attempt at all to get the laptop's audio into the phone's video recording at the same time as that recording was being taken. Instead, I'd use video editing software after all the music creation and video recording were finished, replacing the audio stream recorded by the phone's microphone with one captured locally on the laptop as doctord recommended.
posted by flabdablet at 1:01 PM on June 5, 2022 [2 favorites]

Thirding that editing the audio into the video afterwards makes sense. If you played laptop audio through normal speakers and recorded that with built in mic on phone it would be easy to sync up in post if that’s part of your goal.

To do this with your Scarlet unit I might try sending signal from the Scarlet to the iPhone with a TRS to 1/4” female adaptor (from scarlet) to your current lightning adaptor into your phone. You can monitor from the scarlets headphone jack, using wired headphones.

You could also monitor while you send audio with a simple 1/4” male to dual female splitter.

For the iPhone end this might work but I really don’t know:
posted by soy bean at 1:27 PM on June 5, 2022

For video editing, DaVinci Resolve is free and powerful. Agreeing with everyone that you want to record your audio and video separately and then sync them after the fact.

You may need to experiment a little to find out what kind of cues you can use for syncing, but once you have a good method, it will reliably get your video and audio tracks close enough.
posted by itesser at 8:10 PM on June 5, 2022

Another course you could take is to use OBS (Open Broadcaster Software) to synchronize all of your sources for live capture and automatically have it muxed to a single output file in the end. The idea here would be:

1. Have the music file in your OBS 'scene' as a media file source
2. Use a plugin like this one to treat your iPhone camera as a live video source in OBS.
3. Enable monitoring on the media track through OBS. This should allow you to listen over headphones connected to your laptop (suggest wired ones for latency reasons, as others have suggested).
4. Record via OBS. The track should play, and the output will include audio from both the iPhone capture and the media track.
posted by Expecto Cilantro at 8:20 PM on June 5, 2022 [1 favorite]

purchased the suggested equipment

Did you buy the Rode SC4 cable? As explained in this video, that's an important component, as it converts the TRS (tip/Ring/sleeve) 1/8" (3.5 mm, same thing) connector that most audio equipment uses to the TRRS (tip/ring/ring/sleeve) that the iPhone lightning-to-3.5mm adapter cable uses. (In phones the "extra" ring connection is so you can use a wired headset with built in microphone.) Without that Rode cable the connections won't line up correctly.

I also need to be able to hear the music in real time through headphones

If you have a little Mackie or Behringer or whatever mixer, plug your headphones into that.

I could hear the computer audio via my AirPods

Not only are people right about the latency in Bluetooth being a problem, but I suspect that once you had your AirPods connected the Phone defaulted to using the mic in the AirPods as your audio input source. So, yeah, you need a wired connection for your headphones.

I have a physical sound card (Focusrite Scarlet 2i4) that I can use if needed.

This could very well be the solution, but a little more info about your setup and goals would be useful. Are you making music live on the laptop and recording a video of that with the iPhone? Are you using the laptop just to playback music while you record a video? Do you have little audio mixer like in your video?
posted by soundguy99 at 6:14 AM on June 6, 2022

Response by poster: Thanks for answers so far. I should have mentioned that I’m already recording music separately and adding it to video later, but I have to do this with dozens of videos and it becomes v time consuming, especially when I have a lot of false starts.

To clarify, I’m recording a video of of an art project (in meatspace, not digital) while creating music in ableton in real time. The physical space I’m working in is a noisy co-working space so I’d like to use headphones (I’m currently using wired, but mentioned AirPods just in case it was possible to reduce the latency somehow. Your answers suggest this is not possible, so thanks for confirming).

I did purchase the rode sc4 cable and set everything up exactly like in the video, but the video only captured audio from the phone mic.

Expecto Cilantro & soy bean, I will test out your suggestions and report back.

Thanks all!
posted by chara at 8:33 PM on June 7, 2022

Ah, okay. If it's live music created in Ableton, the method I suggested will need a slight tweak:

Instead of picking a media file source for an audio input in OBS, you can just add an "Audio Output Capture" source as your audio input in OBS. (Make sure this audio input does not have monitoring enabled in OBS, or else you may cause an echo loop). The rest of the steps (iPhone camera as video source, etc.) should apply as normal.
posted by Expecto Cilantro at 4:14 PM on June 8, 2022

« Older NOLA dinner tonight   |   Mint is not so fresh anymore Newer »
This thread is closed to new comments.