Tuesday, December 2, 2014

Volume Ducking - A Way Of Thinking

My wife and I were recently trying to participate in a conference with my daughter and some other folks at her house through Skype. My four-year-old granddaughter was getting bored, and so my daughter turned on the TV for her. From that point, they could not hear us talk, which was frustrating and a bit of a mystery, and we struggled with that through the rest of the conference.

Afterwards, I researched the problem and learned that this was due to Skype being a "half-duplex" audio mode, which basically means that it will transmit sound only in one direction at a time. The direction of transmission is governed by the relative volumes at the two ends - whoever is making the most noise gets transmitted, while the other party is not heard. This mode is called "volume ducking" - the lower volume gets "ducked", or shut off.

The reason for doing this is to prevent feedback from occurring, due to the sound of Party A's transmission feeding back through Party B's speakers. Until Microsoft took over Skype, there was an option to disable volume ducking, which was useful when both parties were using headphones, which themselves prevent the feedback. But Microsoft eliminated that option for Windows and Android platforms. Strangely, they kept it for Mac and iOS platforms, at least for now. It's like the're punishing their own customers.

You might note that the same mode is generally used for cellphones in Speaker Mode. So, if someone is on the road or in another noisy environment and using Speaker Mode, the other party needs to speak loudly, in order to overcome the background noise. Also, on Skype, you can get some improvement by having the party in the noisy environment turn off the automatic volume adjustment. That, at least prevents the ambient noise from being amplified.

It might also be helpful to remember your push-to-talk radio protocols, where only one person talked at a time and indicated that he was finished transmitting and was ready to listen by saying "Over".

I've also learned that people doing remote interviews on TV usually use Skype, but they have an arrangement where they use two channels - one dedicated to each Party's transmissions - so they can babble on simultaneously, although the lag in transmission time is also a hindrance to that, thankfully.

As an engineer, I took some ribbing from my colleagues for my penchant for looking for patterns and making analogies between seemingly dis-similar systems. I suppose it was sort of my way of giving homage to the search for the Unification Theory. But it was also a very useful tool for making extensions of logic. And, in truth, the ribbing was pretty limited, because I made a lot of  folks a lot of money that way. And I think I see some significant analogies between this volume ducking problem and the way people's communication has evolved, in general.

Perhaps my memory of the "Good Old Days" is a bit idealized, but I seem to remember being taught that common courtesy demanded that you listened to other persons speak, then you spoke while they listened, and so forth; so, push-to-talk radio wasn't that much different from the way we normally conversed. Even the early Presidential Debates were conducted in this manner. Also, journalists in that era held to a code of unbiased integrity and tried to give us an unslanted window into the world.

Then the MTV era of fast cuts and reduced attention span gradually took hold and we started relying more on 10-second sound bites as our preferred source of information. Then Rupert Murdoch set up Fox News as an overt right-wing political tool, eliminating unbiased integrity entirely. Then gradually, other mainstream media news turned more and more to semi-literate beautiful talking heads, taking their cues from their producers' desperate struggles for ratings. Well, nothing sells like controversy, so now we see these shows set up specifically designed to give us screaming matches, with moderators skillfully adept at bringing out the worst in their guests. And the guests are the shrillest voices they can find, because they know our brains have become half-duplex processors - we only hear the loudest voice!

Volume ducking. Our modern world's way of thinking.