The Challenges of Playing Music Together Online

This week I've been spending a good bit of time watching video tutorials about how to make online rehearsals or multi-player performance videos possible. I can send you some links, if you'd like.  You've probably seen them in the past few weeks, musicians playing TOGETHER, on screen, in the age of social distancing. And you would not be alone in thinking . . . let's do that, that looks like fun! And, on top of that, it would get us back to playing together as an ensemble.

Yes, it would be great!

But . . .  :(

The truth is that those folks are NOT playing or singing together in REAL TIME.

The problem that everyone faces when confronting the challenge of playing music together over the internet - whether it be two people playing a duet, three singers singing a song together, or a whole chorus or orchestra playing as an ensemble - is that it takes time for one person's electronic sound to reach another person (or persons).

WARNING: reading past this point may cause your eyes to glaze over. Good luck!

Even traveling at the speed of light through glass (your internet communications travel via infra-red “light”, the wavelength used over long distance optic fiber, at 200,000 km/sec, the speed of light through glass). However, on the way, the data also has to pass through a variety of supporting network components, such as network routers and optical transceivers, which slows down the average speed a bit. This slowing down is called latency. Signals that travel through optical network cables at this speed add roughly 3 milliseconds of latency for every 588 km traveled. And thus, the fastest that audio can circle the globe is in about 200 milliseconds.

Here's a real world example. Major League Baseball hitters talk about the speed of trying to watch a fastball from the moment it leaves the pitcher's hand until it crosses the plate. It actually happens too fast to react in real time. Hitters instead look for movement, which allows them to predict where the ball will go. It takes about 300–400ms for the ball to arrive at the plate, roughly the same amount of time it takes to blink an eye, and batters have about 150ms to react before it’s too late to even swing the bat.

According to mathematician and physicist Philippe Kahn, we still have one main challenge that prevents musicians from being able to achieve a real-time experience: Einstein’s relativity theory that nothing can travel faster than the speed of light. Here's how Kahn puts it, "No matter how efficient the network and equipment, latency is unavoidable. Therefore the problem of real-time remote music performance comes down to “What is the acceptable latency?” My personal opinion is that a consistent 10ms is a minimum to serve all musical styles. The less the better. But there is always going to be some latency. You can’t beat Einstein and the laws of physics, except in science fiction books where we travel in time, which is a lot of fun!"

The speed of light has about 5ms latency over a distance of 1500km. A network connection, under perfect conditions, cannot go faster than this. Unfortunately, most of us don’t have perfect network connections. We’re stuck with network traffic and trying to balance fluctuations from multiple musicians trying to connect with varied latencies. Achieving a real-time feel online won’t work for music despite our brain’s ability to learn how to compensate and predict. **

So . . . HELLO OUT THERE! ARE YOU STILL AWAKE? Close your eyes for a second before you call it quits. We're almost done!

With all that in mind, I'm trying to formulate a way that we can meet together online and do some collaborative rehearsing, and maybe even some sharing of music that we have been working on with all this "spare time" many of us have on our hands!

But that's for another post. For the moment, let's enjoy some music that we could play online without any fears of latency . . . a piece written for solo instrument - and NOT for piano! Here's a wonderful performance of Telemann's Fantasia in A minor for solo flute (a piece that I enjoyed playing in my youth when flute was my instrument of choice). Enjoy.

Telemann: Fantasia No. 2 in A Minor (Aisling Agnew, baroque flute)

** much of this is thanks to Caleb Dolister's Why can’t musicians jam with each other online without latency or other issues? Thank you, Mr. Dolister!