Talking Zoom sound quality

Community Open Mic Events Tech Talk - How to setup Zoom / Audio / Video
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I’ve not yet listened to the recording, but I suspect that’s down to bandwidth.

When in a Zoom meeting by yourself, there is only one audio/video stream for your Internet connection (and the upstream connections to the Zoom servers) to deal with. When in a conference with others, there’s far more data flying around.

The algorithms used for video calling will, typically, adjust the data rate when they start to see congestion. This means reducing the quality of the audio and/or video.

Music stresses these sorts of service more than normal speech because there are fewer gaps, more content. That means more data.

Oh, and a dirty little secret of how the Internet works: incoming data generates, and requires, some outgoing data (and vice versa) so if you are on an asymmetric Internet service, congestion in your upstream can limit the amount of downstream data you can receive.

The other thing is making sure everyone else i=on the call is either on headsets or muted. If they are not this will cause echo. There are echo cancellation algorithms but they are not perfect and are mostly designed to work with voice, not with music.

Cheers,

Keith

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Based on what we observed it didn’t look like a bandwidth issue. Usually video is first to go with that. We had some performers where they had bandwidth issues where that happened - video interrupted but audio fine. Phil’s video was fine the whole time. Phil’s sounded like echo or noise cancellation, either in his drivers/OS or Zoom.

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Oh, it’s is absolutely, 100%, no question using a lossy format. There’s never been a case where tools like Zoom have used anything but lossy formats.

It’s a fundamental part of how they work and, more importantly, it’s adaptive. So as the quality of the connection changes (due to congestion, packet loss, latency, etc.) so will the quality of the audio and video. You can’t do that with a lossless format.

Hence, if you have congestion, it can cause lower quality, and the more data you are trying to use, the more congestion is likely to occur.

So, yes, I would suggest turning off all cameras except for the performer.

And then, on top of that, echo cancellation can further mess things up because, fundamentally, if you aren’t using a headset or monitoring on headphones, your computer is trying to prevent feedback between your speakers and microphone. That is, effectively, what echo cancellation is (it’s call “echo cahcellation” rather than “feedback suppression” because there’s some latency involved, but it’s basically feedback control). Modern echo cancellation is pretty good, but it’s a long way from perfect.

Multiply the effect of this by however many people are in the conference who aren’t using headsets and aren’t muted, and you can end up with a big old mess.

I would say the mute policy is the number one thing you can do to prevent problems as, regardless of Internet bandwidth or quality, echo cancellation will cause degredation.

Cheers,

Keith

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@Majik Thanks again, Keith. And this explains why solo tests conducted prior to the event creating a Zoom meeting with yourself as the only participant is not going to be representative of performance during the event.

It makes me wonder if there is another hosting options that allows the positives of this being an online, all-in-room, virtual event with better management of the audio and video quality plus the convenient logistics of Zoom (courtesy of Adrian’s use of a license)

Apologies, Phil, I think I will move this in due course to a more appropriate Topic.

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The only ones I am familiar with are things like Jamulus which focus on high-quality, relatively-low-latency audio streaming (low-latency for OM type scenarios isn’t really important). These don’t tend to include video capability because that’s not quite their intended use. there are ways you can use them alongside video though.

However, IMO they tend to be too complex to set up for many people and, thus, probably not suitable for OMs without a lot of work.

Tools like Zoom, Teams and Google Meet are nice in that they are nicely packaged and, in a lot of cases, people are already familiar with them. They are not ideal for OMs though.

There may be a better alternative out there, but it’s unlikely to be one of the standard business-focused video-conferencing or online-game collaboration systems.

Cheers,

Keith

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Thanks Keith. I guess for our purpose Zoom generally does OK. If we manage the muting, turn off video, ensure participants use Original Sound without Echo cancellation we are generally OK. Appreciate you sharing your knowledge on this.

BTW, hope the party was good, and you doing OK today :wink:

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I agree with @Majik 100% that muting everyone while a performer is on is critical for good audio quality.

However Phil was not experiencing bandwidth issues. Degradation due to bandwidth is first experienced as video issues, and then audio quality degradation similar to going from MP3 → FM radio → AM radio. Or potentially freezing and catch-ups affecting both audio and video. Neither of those were the case.

It was most definitely a feedback / echo cancelling issue based on what was observed.

I thought it was great that many people kept their video active at this OM. I think it added to the sense of community and being an event. It would be a shame if people had to have their video off. Perhaps turning it off if anyone has a poor connection makes sense - however I don’t think a blanket rule is necessary.

On Zoom being lossy compression: almost everything people are listening to, outside of their DAW, is lossy. That doesn’t mean it’s bad. YouTube is lossy, so is Spotify, etc. Here’s some details on Zoom’s high fidelity music mode. It’s 192kbps stereo, which is higher quality than the default Spotify settings. So it’s more than good enough for an OM. So nothing to be concerned about.

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I do all this stuff on my phone. I’ve got a choice, either watch the performer or swipe the screen across and watch the gallery. So I of course watch the performer. Having all the videos switched off would therefore not be an issue for a phone user. I’m assuming if you watch on a computer/laptop or whatever you can see both the performer and the gallery at the same time?
Also when using a phone if you want to add a chat comment you have to exit the screen and can no longer see the performer.

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Turning video off on request would need to be maintained. New performers might not know if it’s going to be an issue for them and that they should ask though. I’m one of the (sometime) performers who has had video connection issues, so much so that I got kicked out entirely at the last bit of my song one time, and had freezing issues other times. We upgraded to Fibre 150 quite some time ago (up to 150 Mbps download speed, up to 75 Mbps upload speed), and although we’re still 2 tiers from the top (Fibre 400, with 400 & 200 download / upload speeds) and Fibre Gigabit (with 1 Gbps & 250 download upload speeds)) the OM is the only time I’ve ever had issues since we upgraded (including streaming tv services), and so I’m not interested in paying the additional cost year round to increase our potential speed again. Be interesting to know what speed others have who don’t have any video issues.

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Yep, on PC/Mac you get the performer, chat window, and a snapshot of a few of the audience at the top of the screen. Or you can select to view the gallery of attendees. So more of a collective feel.

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I would imagine it would be totally fair to have video turned off on request?

There should be no need to upgrade your internet btw Mari, you’ve already got a speed about 10x faster than what Zoom needs, and around twice as fast as mine.

If your internet connection is fast and stable and you still have connection issues it’s usually either a device problem or a WiFi problem. There are a bunch of other potential temporary issues (e.g. Zoom server issues, temporary ISP issues, etc). Usually it’s local WiFi, though, in my experience.

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Thanks for that info, JK. I’m not sure if it’s good or bad to know my internet connection is twice as fast as yours and I have issues and you don’t!

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Yes, THIS!

If you are able, connect your device to your router with a cable.

If you aren’t, try to check your WiFi is stable and is giving you a good signal in the location you are performing from.

Ideally you should try to put your WiFi on a different channel range from nearby neighbours, but this isn’t an easy thing to do.

For the record, my Internet at home in the UK is only 40Mb down and 10Mb up, but it works fine for Zoom meetings.

Cheers,

Keith

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I can validate this. The quality of my reception and the stream of my performance is fine since I drilled a hole through the wall to connect my PC to the router with a cable.

I also make sure during my performance that nobody else in the house is accessing the internet for any reason, so I am the sole user.

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Out here in the Normandy sticks I only get 18 mb down (have seen 30 a few times) and 3 mb up, that’s ethernet not wifi . Most of my Zoom OMs have been stable.
:sunglasses:

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I guess the good thing is that paying more for internet won’t be necessary. Maybe spending money in other areas might be.

If WiFi is the issue (and it almost always - but not always is) - there are a couple of ways to try to solve the problem.

One is hardwiring and using an ethernet cable like @Majik and @DavidP offered. This will definitely solve it if WiFi is the issue - as it cuts out WiFi.

Or tweaking WiFi settings like @Majik suggested - requires a bit of tech savvy.

Or, you could get an advanced mesh WiFi system. Most people use their ISP’s routers and generally they have very BAD WiFi. Usually they’re the worst, cheapest systems. More advanced mesh systems can be expensive, but can be very, very good. For a few years now they’ve also been easy to setup.

I have a NetGear Orbi system https://www.netgear.com/au/home/wifi/mesh/ and it works very well. It automatically finds the right signal channel and gets coverage all over my house, inside and outside. I get full speed with no dropouts over WiFi from the other side of the house. A better router can also ensure fair sharing of your internet connection - e.g. if my wife is doing work, kids are streaming Disney & I’m zooming - no issues, it all works fine together.

Having said all that - it could also be your laptop/PC, if it’s underpowered, poorly set up or even has bad WiFi drivers or driver settings. There are a lot of variables to network performance unfortunately.

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@jkahn

Very interesting, JK, I’ve learned something new. If I ever struggle at home, particularly streaming on the TV which is quite some distance from the router I’ll know what to do.

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I have 5 TP Link repeaters at various point around the house. The main one connected to the Router creates a LAN out of the wiring circuit and you just plug the slave unit in where you need them. Most have an ethernet port so you can also hard wire, Probably not as powerful or up to date as those Netgear ones and my external signal is a bit iffy. But I live in a French country house built in 1860 with stone walls 80 cm thick. :sunglasses:

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Thank you for all that info JK. Hard wiring is not an option, too many walls and ceilings to go thru. Temporarily plugging in won’t work either, too far away. I don’t think it’s my laptop, it’s fairly new and I had input from our IT consultant at work to buy something with decent specs. I will check the wifi strength as @Majik suggests and also check out what kind of router I have and what I might be able to change too, depending on cost.

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My question regards Zoom closing out GarageBand during the OpenMic event. I travel for a living so I access Zoom calls on my iPad Pro. I also run my guitar through a USB interface into GarageBand on the same iPAd. When I start Zoom it kills GarageBand and so I cannot play my guitar and be a part of the venue/meeting which is problematic. Is there a work-around to be able to run GarageBand and Zoom at the same time? Otherwise I am out of luck wrt these events while i am traveling.