Quote:
Originally Posted by Travis Hoffman
I think the original tape had audio issues when I did the dubbing - not sure if it was a bad VCR audio connection at the event or FIRST's audio was a bit messed up. Luckily the visuals are ok.
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Just realized I should give people a heads up about this, since I have a reasonable idea what happened. LSR looked to be having a similar issue. While I was ducked behind the video table setting up my computer to record, a mentor from another team asked if I could fix the audio at the table. There was next to nothing coming out of the monitor speaker, but strangely, the audio would come back if I shook the speaker and/or table. Long story short (haha, wait for it):
Our AV crew split out the audio in about the worst way possible. They ran the field feed through an equalizer and ground lift, then into one of the ugliest AV hacks I've seen. A single audio feed was run into a panel of 3 pin connectors. All the 3-pins were wired in parallel. So pin 1 of the first connector was connected to all the other pin 1s, etc. Out of this was a spaghetti of 3-pin to RCA adapter cables. This is the equivalent of stacking up a ton of those headphone splitters till you have enough outputs. This does two things. First, the audio level drops by 3 dB every time the number of VCRs connected doubles. So if 8 teams are recording, the audio drops 9 dB. Only bad if you set up your levels and then 15 other teams hook up behind you. The more important consequence is that if a single one of those RCA to 3-pin cables gets shorted out, everyone loses audio. At LSR, a single one of these RCAs ended up shoved under a DVD recorder and was shorting.
I, personally, saw this kind of thing coming and had already rigged up an adapter cable to come out a spare output on the EQ. But that was a bit of an expert move only recommended for people that know what balanced audio is and the potential problems it can cause.
My recommendations for those of you stuck with what FIRST gives you is to look in the back of the AV rack briefly and see if all your audio is coming out of a horrible thing where all the backs of the connectors are wired together. If so, I'd wander by the AV station before anything important happens and make sure you have audio. If not, check all the RCA connectors and make sure one isn't shorting out. If you have someone to spare to stand by the AV station and help everyone out, have that person unplug all cables coming out of the horrible paralleled panel, and connect cables back into the panel only as needed.
Ok, not quite as brief as I thought it would be, but still. If audio was fine one day and crappy the next, I'd lay good odds that one of those spare RCAs was shorting somewhere. And I'd watch out for the exact same problem in Atlanta.