Audio Basics, Episode 1: Signals, Waves, Mixing, and the Physics of Audio 

Thank you!

I will definitely be covering analog vs digital. I want to make sure that I cover the basic concepts of audio first before I get into that. Sort of a layer on top of the other ground work I'm laying here.

I don't have an issue making it available, but it still needs a little bit of polish before I can unleash it to the world.

Unbalanced work fine for consumer electronics. And for short runs of just a few feet/meters, they're usually not a problem. But it would be a better world if all audio connections were balanced.

@@djp_video Wow, a reply! Thank you! Coming from IT originally, the mentality of not optimizing away unbalanced audio is a bit jarring. That it hasn't happened has always implied some fundamental barrier to me.

Common mode rejection!

@@Andreas-ov2fv The same concept is used in IT as well. Ethernet and USB, for example, use balanced signals for data communication, though that particular term isn't really used in that context. But it is the same.

Those are the exact symptoms of having an unbalanced, stereo audio source being plugged into a monaural balanced input. An incompatibility between balanced and unbalanced connections. As demonstrated in the video, the audio that the switcher "hears" on its input is the *difference* between the signal on tip and ring of the connected cable. If the connected source is stereo (rather than balanced), that device is putting the left audio channel on the tip and the right audio channel on the ring. So at the input, the switcher is getting the left channel where it's expecting the hot (+) side and right channel where it's expecting tthe cold (-) side of a balanced signal. Since the audio that the switcher hears is the difference between what is on the left vs right channel, you only hear sounds that are either in the left or right channel, but anything in both gets cancelled out and removed. That, and everything that does come through from the right channel has its phase inverted, creating a weird spacious, behind- or above-you rather than distinct in-front-of-you sound. The fix is to use the right cable. If you have a stereo unbalanced source that you want to connect to balanced audio inputs, you need a cable that splits the signal into two separate wires -- one for the left, and one for the right. So one end of the cable would have a TRS (or mini TRS) for stereo and the other end of the cable would have two TS connectors to split that into left and right. Something like this: amzn.to/45MSQ8M If you're already using an insert cable and still have the problem, that's a sign that the ground (sleeve) connection is broken and the cable needs to be repaired or replaced.

It's the combination of the tones heard at 6:35 and 6:38.

@@djp_video I guess this is why I'm in video and not audio. 😂 How is the inverse signal generated that travels down the 3rd XLR pin?

@@daltonrandall4348 It's literally just the inverse voltage... reversing the +-/ sign. So, if at one moment in time the voltage on the (+) wire is +1.0V, the other (-) wire would be - 1.0V. Or when the signal on the (+) wire is - 0.5V the (-) wire is simultaneously +0.5V. They always mirror each other -- at least at the source anyway before noise is picked up by the cable. (Remember that even the normal/hot/+ signal goes both above and below the baseline, so it's a positive voltage for roughly the same amount of time as it is negative; we just use the + and - or hot and cold designations to indicate which signal is the original and which is inverted.) It really is that simple. Looking at it on the graphs in the video, it's exactly the same signal, just flipped upside down.

@@djp_video Cool, thanks.