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Ask HN: Video conferencing that works with group singing?

21 points by kermitime ↗ HN
Hello. Could you recommend any video conferencing services that would work with group singing?

I work with two organizations that use video conferencing apps for online classes. During these online classes, the participants sing together (10-20 people). The problem we're having is that the voices are out of sync. I assume this is because of the different latency participants have with the server.

We have tried zoom.us, webex, hangouts, skype-- same problem across all apps (out of sync singing).

I don't know enough about video conferencing technology to know what to look for in terms of features. Perhaps a service that lets me adjust the latency of each participant manually? Or a service that dynamically adjusts for latency in a way that makes in-sync group singing possible?

Any help the HN community could provide is much appreciated!

23 comments

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j88439h84
What about Whereby?
kermitime
Oh right, this is the new appear.in. I remember really liking how easy it is to join rooms. Going to give this another look. Thank you!
djaque
Unfortunately that will be really tough. I have a live audio background and the recommendation I have always heard is to keep the latency of your signal path at the 1 ms level when dealing with monitoring applications. That's a solid order of magnitude below what is common for VOIP let alone video. You could maybe get away with audio only, but round trip latency is still getting up there.

Edit: I know of some pro-grade point to point audio solutions that are able to handle this problem, but I'm unsure if there's anything consumer ready.

j88439h84
> keep the latency of your signal path at the 1 ms level

NYC->LA at the speed of light in a vacuum

4000 km / c = 13 ms

Slower in fiber; apparently about 19 ms.

cactus2093
Wow 1 ms seems fast. I don’t do any live sound, but I’ve read that 10ms is touted as the cutoff point below which most humans can’t detect any latency.
pbowyer
Have you any experience with http://cleanfeed.net/ or https://ipdtl.com/ or squadcast.fm?

I'm assuming they are good for interviews because you can correctly merge the separate audio tracks later, rather than because they keep the latency down?

kermitime
I'm not familiar with any of these but I'm going to check them out. Thank you!
kermitime
Thanks for the pro-level reference. I'll keep this in mind in case we ever get into recording. For now we're just trying to get non-singers/total beginners to sing together without fear of embarrassment.
jedieaston
Discord has <200ms latency for audio chat. Is that sufficient? Not Enterprise ready but it may not matter for your use case.
kermitime
Discord will be what I use in my next attempt with a test group. And I don't know if it will work but I'll try it along with the other suggestions (slower, longer tone music and perhaps some lead singers turned up more). Thanks!
mgamache
you really need to be < 20ms latency to coordinate multiple instruments (voices).

The best solution is JamKazam https://www.jamkazam.com/ (I have no affiliation and have not used the product in years)

You'll each need a good interface and Ethernet connections. A good interface on windows would typically have an ASIO driver. This is not an easy thing for more then a few people. Note: Jamkazam also makes an all-in-one device (JAMBLASTER).

kermitime
This looks really cool. I have a feeling that most of our participants won't be able to set up ethernet-based connections and use special hardware. Worth more investigation on my end before I assume too much. Thank you!
jtl999
If you can get by with audio only I'd recommend Mumble with a strategically placed location of the server (to keep latency consistent between users assuming no routing shenanigans, need to test for this) and hope for the best.
kermitime
I'll give Mumble a try. Thank you!
feliksik
One way is achieving low latency, which is technically super hard, as others point out. Keep in mind that another way is selecting less latency sensitive music, "slower" music with longer held tones. But that's a style change.
kermitime
Wow this is an interesting comment. I hadn't considered changing the music in this way. I'll give it a try. Thank you!
abundanceof
Hey Kemitime, I'm trying to solve this problem at the moment. I'm looking to have a couple of people leading the singing, with others following on from where they are, with their mics down.
kermitime
Fascinating. This feels compatible with our setup -- where the group leaders are in the same physical location with one mic and the participants are all remote. I'm going to test this idea out soon. Thank you!
Stevvo
There is a big market for this right now; churches across the world want to do group singing remotely just as they would do together a regular Sunday service.
topkai22
Semi off-topic, but the development of solution for this problem is a minor plot thread in "Rainbow's End" by Verner Vinge, which was a fairly popular sci-fi book with some really cool "near-future" predictions.
sigmaprimus
I just spoke to a friend regarding your issue, they said at their company they ran into a similar situation.

Their solution was to use Zoom Video Conferencing, apparently they have the option to have users phone in or have Zoom call users over the telecom network for audio whilst receiving video over the internet.

I didn't ask on costs, but it might be a viable solution.

  Edit>> I see you tried zoom, did you try the telecom audio solution?
kermitime
I'll see what happens when we go video over the internet and audio over phones. Thanks!
joshwa
Hi OP, did you ever find a good solution for this? Trying to set something up for my daughter's kindergarten class.

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