Limited number of participants?

[peterb123]

I've been looking at jamkazam for this reason - can we set-up a way to play (classical) music as an orchestra online? At first I was sad to have sold my viola as playing would be really fun to try through here, and I feel useless as an orchestral conductor these days. But all your descriptions actually fit very closely to my experience as a conductor: a group of musicians will slow down to a crawl if they only wait to hear the other, and the conductor rescues the situation by gesturing ahead of the sound. Bad/inexperienced conductors start only to listen and because of the latency (some orchestra's will play more then a full second behind your beat!) lose tempo. And in my previous life as an orchestral player have learned that in some instances you should not listen to your colleagues and in other instances you must.
My questions: is the total latency of the group's sound a sum of all the player's latencies or is the slowest in the group the one that determines the latency? And has anyone tried working with a conductor (visual leader)?

[Hans Peter Augustesen]

There is no reason/meaning in "the total latency of the group's sound".

it does not exist.

Total latency is between you and one other participants.

To one it can be 20 ms.

To another it can 30 ms.

And to a third it can be 25ms.

And so on

[Hans Peter Augustesen]

And yes

You can set-up a way to play. Classical or whatever

A group of musicians will NOT slow down to a crawl.

Not at all - if the latency is about 20ms. To all participants.

20 milliseconds is nearly perfect - or GOOD, as it is called in JamKazam terms.

If the latency comes over 20ms the problems will begin, of course.

As a example: I have a connection to one person 60 miles away. The total latency is about 18 milliseconds.

Of course it would be better with 10ms - and you can actually obtain that, if your audio gear and connections is very good and the distance between you all is low.

Look here - eventually:

LATENCY, mostly TOTAL LATENCY
> https://forum.jamkazam.com/showthread.php?tid=171

[mhholmes]

Hi. Does jamkazam has an adminstrational or technical limitation in numbers of participants? I want to set-up a choir rehearsal with about 20 singers. Thx, Chris

I don't know if there is a specific limit, but it's my understanding that JanKazam achieves low latency by having each participating computer send its audio directly to the other participants (rather than to a central sever). So for a 20 person choir, each participant computer would be sending its audio packets to 19 other computers, and also receiving audio from those 19 computers. Clearly all that activity will cause some added latency as you add more participants.

By the way, sending and receiving video also seems to affect latency. My quartet has been using JK succesfully for a few weeks now, but it does seem to increase our latency when we use video, so we mostly do not.

[Hans Peter Augustesen]

There is in principal no limits for amount of participants.

But there is a practical, so to speak.

That is the capacity of peoples internet connections.

Here is some from another post in forum:

"TEST NETWORK tell about the quality and quantity of the internet connection.
For example how may particitants the connection can support in a session; audio and video.

When I did TEST NETWORK - when it work - my connection could support 8 in a session + 3 or 4 of them with video

Some connections can only support for example 3 with 1 video

I have never heard about a connection that can support more than 8.

Keep that in mind! You will learn by the hard way - sessions breaks apart"

Until I get to know (from JamKazam etc) it is my firm belief that it is correct with 8. It is a practical experience, too - from sessions.

But it's been a long time since I completed TEST NETWORK. At least a year.

Maybe something has changed

[hwalman]

I have never heard of a connection that can support more than 8 in a session.

If 8 is the maximum that a connection can support - then the maximum in a session is 8, of course.

And ALL those 8 must have a connection that support 8.

Maybe some connections can support for example 16 or 32 - who knows?

But it will still require that all the other 15 or 31 also can do the same.

---

I have NEVER been in a session with more than 8 that actually sounded well - for more than a few seconds.

9 = unpleasant
10 = awful
11 = disguisting
12 = where is the leave button?
13 = I can not breathe
14 = tell them I love them
15 = ???

Hi. I am working with a chorus of around 35 people before COVID hit. We are trying to get as many people to use JamKazam simultaneously as possible. We have figured out that each additional PC that logs into a session adds about 325 Kilobit/second of data for both sending and receiving for everyone in the session. So if there are 10 participants, there will be about 3.25 MegaBits/second data sending and receiving for everyone. This makes it clear that it is important that everyone in the session has good high-bandwidth service from their internet service provider. This can be checked by each person by running an internet speed test with their browser. We use this one: https://www.speedtest.net/ . Here, pay attention to the UPLOAD Mbps result. This is typically the bottle neck in your internet connection. This has to be greater than the bandwidth generated by all the people in the session. If it is not greater, you are going to have a bad session!
Another useful thing we found is that there is an option in JamKazam to reduce the bandwidth of the audio data that is being sent out from a participant in the session. Click the "Manage" tab in the upper left corner, then click on "Audio Settings" and then "Audio Booster". In the window that pops up, you will see a setting called "Maximum Outgoing Music Bitrate". During an active session, this setting can be reduced to 128 Kbps. This greatly reduces the bandwidth sent out by the participant. We have had all our participants do this and it helps keeping the total bandwidth of the session down. It does not seem to greatly degrade the audio quality. So far, we have been able to have up to 13 participants in a session with good results. We are hoping to add more and see how it holds up. Good luck, Hans.

[blandis]

Another often-missed consideration regarding your bandwidth and JamKazam performance: Internet performance for a participant will be affected if others in the household are using the Internet connection at the same time. For example: kids playing online video games, or streaming movies, etc.

[Fran]

I’m so encouraged to know that at least one person has a quartet going. My playing friends are scattered about the Welsh marches and so far we’ve only had real success with  duets and trios. The only time we’ve succeeded with 4 is where a married couple have a dual connection to one computer. That’s a group with guitar, accordion, cello and recorder, although our usual groups are S, A, T and B recorders.

I’m interested in the distance aspect. I’ve played duets with a friend about 140 miles away with no problem but as I say my nearer friends get too much latency when we get 4 players together. I’m amazed to hear that 8 is possible. Is it just a matter of luck, good broadband speeds and the right equipment? I would say most of our equipment is pretty basic...what should we be getting to improve matters?

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I have never heard of a connection that can support more than 8 in a session.

If 8 is the maximum that a connection can support - then the maximum in a session is 8, of course.

And ALL those 8 must have a connection that support 8.

Maybe some connections can support for example 16 or 32 - who knows?

But it will still require that all the other 15 or 31 also can do the same.

---

I have NEVER been in a session with more than 8 that actually sounded well - for more than a few seconds.

9 = unpleasant
10 = awful
11 = disguisting
12 = where is the leave button?
13 = I can not breathe
14 = tell them I love them
15 = ???

Hi. I am working with a chorus of around 35 people before COVID hit. We are trying to get as many people to use JamKazam simultaneously as possible. We have figured out that each additional PC that logs into a session adds about 325 Kilobit/second of data for both sending and receiving for everyone in the session. So if there are 10 participants, there will be about 3.25 MegaBits/second data sending and receiving for everyone. This makes it clear that it is important that everyone in the session has good high-bandwidth service from their internet service provider. This can be checked by each person by running an internet speed test with their browser. We use this one: https://www.speedtest.net/ . Here, pay attention to the UPLOAD Mbps result. This is typically the bottle neck in your internet connection. This has to be greater than the bandwidth generated by all the people in the session. If it is not greater, you are going to have a bad session!
Another useful thing we found is that there is an option in JamKazam to reduce the bandwidth of the audio data that is being sent out from a participant in the session. Click the "Manage" tab in the upper left corner, then click on "Audio Settings" and then "Audio Booster". In the window that pops up, you will see a setting called "Maximum Outgoing Music Bitrate". During an active session, this setting can be reduced to 128 Kbps. This greatly reduces the bandwidth sent out by the participant. We have had all our participants do this and it helps keeping the total bandwidth of the session down. It does not seem to greatly degrade the audio quality. So far, we have been able to have up to 13 participants in a session with good results. We are hoping to add more and see how it holds up. Good luck, Hans.

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I’ve just seen the instructions given by the musician with 13 singers...well done! Will try all you advise re speed test etc. Thanks! Fran

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Another often-missed consideration regarding your bandwidth and JamKazam performance:  Internet performance for a participant will be affected if others in the household are using the Internet connection at the same time.  For example: kids playing online video games, or streaming movies, etc.

Yes, some of my friends won’t join in because their partner/family wouldn’t be able to use the internet at the same time...frankly I think it’s a pity if they can’t find something else to do for an hour or so!  Fran

[Sharpie]

JK's current peer-to-peer architecture means that an individual musician's internet link is the limiting factor on how many you can effectively use JK with at once - in a group that means the one with the highest latency/least bandwidth connection. I've been using Jamulus for some months - it is a client-server architecture so everyone connects to a central server, and you only ever have one audio channel to/from the server no matter how many people are making music together. It's less feature rich than JK but very easy to set up and use - and arguably scales better for larger groups if the server you're using is up to the job. You can use one of the many public servers, or set up your own private one very easily (I use an Amazon Web Services free tier for this).

I used JK at the start of lockdown but found it too buggy and gave up - I'm now trying again, as the client seems much more stable now.