obsolete.computer/audio/

RFH and Pasamala Reunion Show

Big Rail Stage

I've been really wanting to start producing some live videos from the shows we put on over at Big Rail, and the reunion of a couple of bands seemed like a good way to start experimenting with the prospect. Pasamala (in two different iterations with different singers) was the band I was in for part of college, and RFH was a group of friends who were performing around the same time (or a little bit later if I remember right).

The core of the recording setup was the same computer + RME A/D converters that we used when recording at Bill's cabin. What's new is Big Rail's PA system which uses an Allen & Heath MixWizard 16:2... bought new old stock because I'm waiting to start using a digital mixer until some time after hell reaches absolute zero. This mixer has 16 direct outs, so I grabbed a couple of TRS-to-DB25 snakes to make interfacing with the RME converters a bit less cumbersome. From there, it was a matter of hitting record on the computer and letting it do its thing.

Afterward, I mixed the audio portion in Mixbus and kept it very simple, trying to keep the workflow streamlined so that the same process can easily be applied to future recordings. The only thing that didn't come out great was the crowd mic, we just need to find a better location for it where it won't pick up bleed from the monitors.

Video

For the video, Darren brough an older camcorder and set it up on a tripod. It came out ok, but people bumped the tripod a few times and changed the angle of the shot. Plus, I did a slight digital zoom to make the stage more visible, and sacrificed a bit of resolution. For the next video project, I'll likely borrow Beth's Canon EOS D5, which has great video quality and she's got a couple of perfect lenses for the live music use case. The part I don't yet have a perfect solution for is synchronization. The two most plausible options would be to either push HDMI wirelessly somehow back to the computer and capture there (since then the capture software could be synchronized with Mixbus and thus the RME word clock), or push LTC generated by Mixbus over a wireless audio system out to the camera. I will have to do more research and see which will work better, and just as importantly, which will grow better (without breaking the bank) as we get more camera angles going.

Poor Man's Sync Solution

It took me a while to figure out the best way to sync up the audio and video in post (hence the musings about LTC synchronization). I ended up pulling both the pre-mixed audio and the camcorder video into Kdenlive. Fortunately I was able to use the audio from the camera to line the video up at the beginning. I found a good strong snare hit in each audio track, and noted the timecode for the frame with the hit. Then I slid the video until the timecodes were the same. So, now the beginning of the show was in sync -- I hard-panned the audio in each track to verify they sounded together (a nice trick to help identify which track is ahead of the other). Since I'd only be keeping one audio track, they didn't have to be perfectly in sync... just good enough to make the snare drum hits look right.

Since the audio and video were not synchronized to the same clock, they were off by about 4 seconds by the end of the recording. To keep the tracks in sync the whole way through, I used the time remap feature. I again identified a strong snare hit, this time at the end of each track, and noted the frame it took place in for each. I then turned on time remap for the video track, entered the original and modified time stamp into the last set of key frames, and Kdenlive did the rest. Now when playing back anywhere in the recording, it was perfectly in sync.

The Results

After adding a few fade-ins and -outs and a simple title overlay to each set, they were ready to render. I did a bit of playing around and found that using Kdenlive's (experimental) GPU-accelerated NVENC rendering sped up the export times by about 4x compared to CPU-only rendering on my rig, which was very nice. And the result looks fine (or at least not any worse than the video was to begin with).

I'm really looking forward to doing this all again with a guest band that would like a live video produced. That way I can focus on the production rather than dividing my attention between that and playing. Though, it was certainly a fun show to play as well.

The RFH Set

Pasamala One (w/ Matt Texter)

Pasamala Two (w/ Ryan Bibza)


Modified Sunday, January 22, 2023