I’ve seen a lot of the Taylor Swift tour on social media recently and noticed that all the singers and musicians are playing wirelessly. Particularly the guitarists who walk around the stage. Couldn’t the signal drop out? And how does it manage to remain in sync the entire time? Especially in a large venue with a lot of interference (e.g., phones, cellular networks etc).
Is the technology just simply good enough? Because surely they wouldn’t take the risk otherwise. Unless it’s all pre recorded – but surely not right?
In: Technology
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Sorry, but you’re one of the more vocal and well educated folks on the av subreddits.
The ELI5 is that nothing is “in sync.” The wireless mics are sending signal and a wireless receiver is “listening” for it.
Wireless audio isn’t transmitting tempo or data or anything like that, they use RF frequencies. Just not the same specific frequencies as radio, etc.
>Couldn’t the signal drop out?
Yes. Happens all the time, it comes right back though, it doesn’t typically permanently disconnect or anything. It’s like losing a radio signal as you drive farther away from a tower.
>And how does it manage to remain in sync the entire time?
Again, there is nothing to “sync.” A mic will be transmitting on a frequency that the receiver is set to pick up.
>Especially in a large venue with a lot of interference (e.g., phones, cellular networks etc).
They’re using different frequencies.
>Is the technology just simply good enough? Because surely they wouldn’t take the risk otherwise.
I mean it’s “fine.” Wireless setups are most practical for large stage productions because laying cable across a stage where numerous performers are moving around a lot is a hazard, and long cable runs (as would be needed on massive stages) can also suffer from issues like signal degradation.
>Unless it’s all pre recorded – but surely not right?
I can guarantee you at least a portion of what you’re hearing during a Taylor Swift show is prerecorded. This is standard practice for nearly any artist of that touring capacity. At small venues even the most incredibly proficient musicians slip up, that wouldn’t fly for an arena act like Taylor.
Source: worked in radio and live sound
Large concerts like this will have dedicated radio system operators who look after all the transmitters and receivers. They can’ be incredibly expensive and sophisticated systems with lots of redundancy and carefully planned channel frequencies and even dynamic channel selection to actively avoid interference or to work around drop outs. The channel allocations are planned around potential conflicts from things like mobile networks, public band radio, TV & radio transmitters etc – which are different in every country. In fact it is often illegal to transmit in certain frequency bands that correspond with other systems.
Each performer will have a transmitter (or more) that sends their voice/instrument to a receiver, plus a receiver which receives the monitor signal from another transmitter. Each performer just plays/sings in time with their in-ear monitors and they will be in sync with everyone else. The wireless signals travel at the speed of light, and the processing in the transceiver systems happens practically instantly.
The wireless units I’ve used are basically a tiny radio station that’s set to one specific frequency. The thing that plugs into your guitar is a transmitter and it’s sending it’s signal to an antenna that’s plugged into your sound equipment. (Amplifiers and stuff.) The frequency it transmits on is what’s important. Different frequencies are set aside for different industries. Even though there’s a lot of other transmissions flying around the concert hall, none of them will be on the frequency of your particular radio station.
They “stay in sync” because it’s a radio signal traveling at the speed of light. It doesn’t take long to travel five or ten meters. Honestly, the hardest part of staying in sync at those shows is the sound itself. Those places can get so big that there’s a delay between the sound coming out of the speakers and the time it takes to hit your eardrums. It’s actually easier to not hear the sound system at all and only hear the sound in your earbuds.
And, yes, things can go wrong. Just like a lot of things can interfere with the signal in your car radio, the same stuff happens here. However, at the zillion-dollar level of a Taylor Swift tour, they have the very best equipment with backups of backups of backups. All the stuff is tested and checked before each show. And even if something does go wrong, it’s only off for a few seconds at most before it gets fixed.
That said, even at the mega-tour level, stuff goes wrong all the time. Usually, the audience doesn’t notice, or it doesn’t cause any major distraction. I’ll bet if you searched through all of the concert footage people have taken of Taylor’s tour, you would find plenty of examples of something going wrong. (Especially if you know the songs and the tour well enough to know how it’s supposed to go.)
The same way your TV or Radio Station doesn’t drop out randomly. Each instrument or mic is transmitting a specific frequency that’s not in the same range as phones or other wireless devices.
There are antennas on the side of the stage pointing towards the instruments to amplify the signal. These antennas are physically connected to a receiver nearby that sends the signal down a physical cable to the FoH desk, where all of the inputs are mixed and sent to the PA.
Source: work in live events
“Sync” is an issue for video (or motion picture) *recording*. If you’re using multiple cameras and recording audio on different devices, they all have to be running at the same clock speed. Since digital video gear may be recording in “frames per second”, each piece of gear can be a bit off regarding what a “second” actually is. A tiny error will compound over time, a millisecond off becomes ten milliseconds off before long (when compared to recording gear with differing errors). So often there’s a master source of time code that’s sent to each piece of recording gear – a “master clock”.
That’s not a thing with wireless systems – their latency is low enough that a band can stay “in sync”. You may be thinking of transmission channels – each wireless unit needs to be on its own frequency, so the transmitter will only be picked up by a single receiver.
Even without wireless, latency is a thing for performers in shows, and the bigger the venue the more apparent it is. When, say, your guitar sound runs through a cable (or a wireless system) to an amp, and a microphone is on the amp, and that mic cable goes through a stage-monitor mixer and then all the way to the sound board at the back of the venue, and it’s zapped around through mixers and effects, then sent back to the stage area on *another* cable carrying the entire mix, through power amplifiers and then to the main PA system – on stage, you can “feel” it, a sense of delay – your amp’s right behind you, but you’re also hearing the monitor signal, the house PA, and the echo of the room. Even though all that audio is electrons traveling near the speed of light, the whole thing adds up to a slight sense of “disconnection”. The first time you start playing larger venues, it’s weird, but you adjust really quickly to it. It’s not significant enough to mess up the performance., and eventually you come to associate it with “big room/big crowd” and it feels kinda cool. (Have played hundreds/thousands of shows, from tiny bars to about 8,000 seats, over 40-50 years. No arenas though!)
Your thinking about it too much
Everything in a concert is using analog signals
Your phone uses digital signals
The difference is analog doesn’t have anything to sync, if you can see it (or in this case detect it) its good
Like FM radio there is a point where it gets bad but for the most part especially in close range everything is perfectly adequate
Your wifi signal though would be digital meaning signal degradation actually results in a significant loss of data that has to be compensated for
Analog-> if you can hear it your good
Digital-> it either works or doesn’t
You’re getting a lot of weird ass answers here.
The ELI5 answer is that all the wireless stuff in a show stays synced because it’s very high quality, expensive equipment that is designed to run at low latency.
Anything that is running wireless has a DSP (digital signal processor) and this is what would cause a lag between the vocalist singing into a mic and the vocal coming out of a monitor. The mics, antennas, receivers, mixers, all that stuff is high quality and designed to work in a music setting.
It’s not at like video or audio streaming. Pretty much what you say into the mic is just converted to a signal (non digitally) and transmitted. On the other side that signal is just converted (again, non digitally) and fed into the the equipment. The circuitry itself is pretty simple and the basics are over century old. Because it’s not digital it happens just about instantaneously and the only factor would be how fast that radio wave can transmit, which is the speed of light so is pretty much negligible.
(SOooo, you could potentially run into a situation where you’re filming cannons or pyro going off and the sound take a second or so to catch up with the visual. If you happen to be recording with remote mics and you want ultimate realism you may need to artificially introduce a delay in the sound. This is an artificial case more suited for a science demonstration than anything you’ll actually on a set.)
There are mics with SMPTE (an additional timestamp) but AFAIK this is only for recording devices.
lots of good answers about performance, but the more important part is that the performer is in sync with their in ear monitor. if everybody syncs to their monitor by the time it gets to the speakers it will be clean
if you try to sing in a big stadium and listen to the stadium sound for feedback it can be kind of disorienting like a speech jammer (it came up for people singing the national anthem because they had to practice to avoid hearing the stadium echoes to stay in time)
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