REPORT OF THE NEC VOICE AND SOUND ANALYSIS LAB
A Real Time, Distributed Performance Class Using SoundJack and Zoom
26 October 2020 (Updated 24 November 2020)
by Ian Howell, DMA & Michaela Kelly, BM
An example of this workflow for a weekly studio class at NEC. Lucas Coura and Cynthia Tseng performing.
Use Cases
This guide describes the setup and workflow to run a distributed performance class. This means that physically remote, digitally connected performers will be able to collaborate with perceptually lagless, real time audio while broadcasting video on Zoom. Non-Performing Participants will be able to receive video from performers and other participants, high quality audio of the performance, and Zoom audio from the other participants. Performers hear each other with no delay. They see each other—and hear and see everyone else—with Zoom’s delay. These solution requires participants to use the solution that is fast enough for their role and no faster, high quality enough and no higher. This allows for both scaling to larger class sizes and the simplest end user experience currently available.
The first (1) workflow requires a separate computer run by a non-participant to act as a Broadcast Hub. This is a simpler workflow, and allows the teacher to use only Zoom and have no knowledge of more advanced technology. It does, however, require an additional person and computer to manage the class. At NEC, we use this solution when hosting outside guest master teachers, as it allows them to participate with the least hassle possible. The second (2) workflow is more complex and requires a Non-Performing Participant act as the Broadcast Hub. This requires less equipment and fewer personnel, but requires a higher level of tech savvy of the person managing the set up—most likely the teacher. We use this setup when running weekly studio classes at NEC.
Table of Contents
Table of Contents
License
Use Cases
Introduction and Requirements
A Distributed Performance Class with a Separate Broadcast Hub
Types of participants
Performer
Non-Performing Participant
Broadcast Hub
Basic overview
Specific connections by participant type
Performers
Non-Performing Participants
Performer or Non-Performing Participant who also acts as Broadcast Hub
Setting up the Broadcast Hub
Audio setup
Secondary device (e.g. iPad, iPhone, second computer)
A Distributed Performance Class without a Separate Broadcast Hub
Types of participants
Performer
Non-Performing Participant
Performer or Non-Performing Participant who also acts as Broadcast Hub
Basic overview
Specific connections by participant type
Performers
Non-Performing Participants
Performer or Non-Performing Participant who also acts as Broadcast Hub
Setting up the Broadcast Hub
Audio setup
Appendix A: HELP! Something Terrible is Happening
Common issues
Appendix B: Session Checklist
Broadcast Hub
Performers
Non-Performing Participants
Appendix C: Can I do Advanced Things?
License
This work is licensed by Ian Howell under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-sa/4.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.
Introduction and Requirements
Performance classes—where collaborative music making is observed and discussed in a group setting—make up a significant portion of any music student’s education. During the 2020 Pandemic, singers especially face challenges that force them into isolated spaces while singing. The need for a virtual solution to this challenge is clear. Software requirements for this workflow—a lagless audio platform for the performers; a laggy video conferencing platform for observers capable of scaling users, recording and streaming, and passing through minimally processed audio; and an audio routing app—could be met with a number of solutions. For the quality, ease of use, features, and existing place within our ecosystem at NEC, I recommend SoundJack (free), Zoom (subscription), and Loopback ($99) respectively. Feel free to experiment with other solutions in place of one or more apps (e.g. JackTrip instead of SoundJack, Jack or BlackHole instead of Loopback), but keep in mind you may save money but lose the time required to tweak the more complex setup.
This guide explores two similar use cases. The first, A Distributed Performance Class with a Separate Broadcast Hub requires an additional computer, but allows the teacher to not have to worry about technology more advance than zoom. The second, A Distributed Performance Class without a Separate Broadcast Hub requires less equipment, but is more complex and likely will require the teacher (or another participant) manage more advanced technology. These workflows overlap significantly—the question is whether the computer that links SoundJack and Zoom also allows that user to send their own microphone audio to all participants—but are presented separately to facilitate their practical implementation.
A Distributed Performance Class with a Separate Broadcast Hub
Types of participants
This workflow presumes three types of participants: (1) Performers (may include the teacher), (2) Non-Performing Participants (may include the teacher), and (3) the Broadcast Hub. Each type of participant requires different technology, and this guide assumes that each individual is capable of using the indicated technology and programs below. Regardless of the setup, someone must host the Zoom call. They will be responsible for recording and/or broadcasting in Zoom, and should set their Zoom audio to the highest possible quality. This workflow presumes a mono or stereo output from Soundjack. Multitrack output is possible and will be addressed in other guides.
Performer
a Soundjack low latency setup, including an Ethernet connection, headphones, and a low latency audio interface. See
a device to run only Zoom video (leave computer audio in Zoom). If using a Fastmusic Box or a computer with four or fewer processor cores, a second device is recommended for the Zoom call.A six core + computer could likely run SoundJack and Zoom at the same time.
Non-Performing Participant
a device to run Zoom. Headphones required.
Broadcast Hub
This person may be a participant on the call (on a second device), or even the teacher. They may or may not be the host of the Zoom call. This use case presumes a dedicated MacOS computer can act as the Broadcast Hub. Solutions for windows computers are outside the scope of this guide. The Broadcast Hub requires an Ethernet connection, but no external audio interface as all audio will be routed internally. The computer must be able to simultaneously run (1) SoundJack (free), (2) Zoom (subscription recommended), and (3) Loopback by Rogue Amoeba ($99). Minimum suggested computer is a two core MacBook Air. The person running the Broadcast Hub should have a second, Zoom connected device with headphones to monitor the quality of the broadcast and participate as a Non-Performer as they wish. The Broadcast Hub’s router must be configured to navigate the NAT firewall as any SoundJack computer would, which likely includes port forwarding. Please see the complete SoundJack Guide for more information.
Basic overview
Everyone must use headphones. No open speakers are allowed. The only exception is that a Non-Performing participant may listen on speakers if they never unmute their Zoom microphone. Or, if they do unmute their microphone, they must use the echo cancellation feature in Zoom. This still may not work 100% of the time.
Performers must either leave computer audio in Zoom or both mute their Zoom mic AND ALSO mute their Zoom computer speakers. It is much easier to leave computer audio.
All Non-Performing Participants should mute their Zoom microphone unless they want to speak. Any unmuted sound they make is broadcast to all performers and Non-Performing Participants.
The Broadcast Hub MUST:
Turn on original sound in Zoom, and in the audio settings menu, disable automatic volume control. In the advanced audio settings disable echo cancellation, turn on high fidelity music mode, and turn on stereo audio.
In SoundJack, mute the self-monitoring fader in the left settings column
Set the input and output in SoundJack and Zoom to connect directly to each other as outlined below.
Specific connections by participant type
NOTE: If your workflow includes recording or broadcasting through Zoom, whatever user does so must turn on “original sound,” and raise the advanced audio settings as though they were the Broadcast hub. Otherwise, you risk recording at a low audio quality.
Performers
connect to Zoom with video only (leave computer audio or do not join it in the first place),
connect to all performers on SoundJack,
connect to the Broadcast Hub on SoundJack.
Non-Performing Participants
join Zoom with headphones, with or without original sound enabled.
Broadcast Hub
connect to performers on SoundJack,
join Zoom call with computer audio, with original sound and the highest audio quality setting on (see below). Note you may have to scroll down to see the “advanced” link.
set input and output (microphone and speakers) in SoundJack and Zoom as explained below.
whoever is host of the Zoom call, right click on video feeds of performers (and possibly of the teacher too) and click “spotlight.” This ensures that all Non-Performing Participants see the performers on their screen. Spotlight as many video feeds as you like. Remove the spotlight if you would like to return to a group discussion setting.
Setting up the Broadcast Hub
Audio setup
Close all applications, including any background Cloud Sync apps or other processes.
Open Loopback
Create a new virtual card (lower left-hand corner of window). Name sound card “Zoom out – SJ in.” By default, there should be a “Pass Thru” source to two output channels:
Create a second virtual card and name it “SJ out – Zoom in.” By default, there should be a “Pass Thru” source to two output channels:
Open Zoom and either start/join meeting
Choose “SJ out – Zoom in” for Microphone and “Zoom out – SJ in” for Speakers
Run SJC app
Open SoundJack.eu in a single Chrome browser
Login and go to Stage. Select Input as “Zoom out- SJ in” and Output as “SJ out – Zoom in”
Set SoundJack sample buffer and network buffer each to 512, audio codec to OPUS 192, and mute fader under VU meter. If Zoom participants hear an echo, make sure this is muted. Set the send channels based on how your performers are sending their streams. If they both send channels: 1 (mono), leave this at send channels: 1 (mono). If one sends stereo, switch to send channels: 2 (stereo). If you hear one or more of the performers in only one ear have them switch to send channels: 2 (dual mono). Once a SoundJack participant switches away from send channels: 1 (mono), you may have to refresh the stage and reconnect to one another to return the call to send channels: 1 (mono). Otherwise you will hear the mono Performer in just one ear.
Connect Broadcast Hub to Performers on the Stage. Your goal is not to have a low latency connection with the Performers. Your goal is to have a rock-solid connection where the latencies to each performer are roughly the same, within 5-10ms. Performers optimize their connection to each other with the lowest settings that work. Raise jitter buffer per performer as high as necessary on the Broadcast Hub. Try to match the latencies using the jitter buffers. If you are used to setting these as low as possible as a SoundJack participant, you may find yourself setting it well above 10. If each performer is sending at a different network buffer, these jitter buffers may be wildly different. Depending on the stability of each performer’s Internet connection, you may need to have them raise their network buffer to 256 (especially if they have Xfinity, Starry, or another non-fiberoptic internet plan). If they do this, make sure that they each lower their jitter buffers on each other to regain the fastest connection possible between them. Start with both performers’ volume faders all the way to the right. Adjust their relative volume if need be.
Reminder: Performers must leave computer audio in Zoom. It is not enough to mute the microphone.
Performers should sing/play a loud, high pitch from their piece to check gain levels before beginning the performance. Try to send as loud a signal as possible without distorting.
Secondary device (e.g. iPad, iPhone, second computer)
Join/start the Zoom meeting with computer audio and headphones.
The second device allows the person running The Broadcast Hub to interact with the participants on Zoom and listen as an observer to ensure all sound sources are coming through correctly, as well as give directions to those on SJ. Whenever this device is unmuted, all performers and Non-Performing Participants will hear you.
At this point, audio from SoundJack should flow to participants on Zoom, and audio from Zoom to the Performers on SoundJack. Best practice is for Non-Performing Participants to mute themselves when not contributing. If you run into issues, please consultAppendix A: HELP! Something Terrible is Happening. As you set up your session, please use Appendix B: Session Checklist to avoid making mistakes in the first place.
A Distributed Performance Class without a Separate Broadcast Hub
Types of participants
This workflow presumes three types of participants: (1) Performers (may include the teacher), (2) Non-Performing Participants (may include the teacher), and (3) a Performer or Non-Performing Participant (again, may be the teacher) who also acts as the Broadcast Hub. Each type of participant requires different technology, and this guide assumes that each individual is capable of using the indicated technology and programs below. Regardless of the setup, someone must host the Zoom call. They will be responsible for recording and/or broadcasting in Zoom, and should set their Zoom audio to the highest possible quality. This workflow presumes a mono or stereo output from Soundjack. Multitrack output is possible and will be addressed in other guides.
Performer
a Soundjack low latency setup, including an Ethernet connection, headphones, and a low latency audio interface. See
a device to run only Zoom video (leave computer audio in Zoom). If using a Fastmusic Box or a computer with four or fewer processor cores, a second device is recommended for the Zoom call.A six core + computer could likely run SoundJack and Zoom at the same time.
Non-Performing Participant:
a device to run Zoom. Headphones required.
Performer or Non-Performing Participant who also acts as Broadcast Hub
The only reason to use this workflow is if this person would also like to participate in the call on the same device that is functioning as the Broadcast Hub. It requires five Loopback virtual audio cards rather than two, and generally speaking is more complex to troubleshoot. It is unlikely that one’s computer will be strong enough to both participate in the SoundJack connection at the lowest possible latencies and also run Zoom. Additionally, any app like Loopback will likely introduce additional latency as an input source. If the teacher wishes to participate as an equal performer, they may want to take a Performer roll and assign a Non-Performing Participant to this role. This person may or may not be the host of the Zoom call. This workflow presumes a dedicated MacOS computer. Solutions for windows computers are outside the scope of this guide.
The Broadcast Hub requires:
an Ethernet connection,
an external audio interface and microphone or the built in MacOS microphone (lower quality)
headphones
The computer must be able to simultaneously run:
SoundJack (free),
Zoom (subscription recommended), and
Loopback by Rogue Amoeba ($99).
Minimum suggested computer is a two core MacBook Air. The router must be configured to navigate the NAT firewall as any SoundJack computer would, which likely includes port forwarding. Please see the complete SoundJack Guide for more information.
Basic overview
Everyone must use headphones. No open speakers are allowed. The only exception is that a Non-Performing participant may listen on speakers if they never unmute their Zoom microphone. Or, if they do unmute their microphone, they must use the echo cancellation feature in Zoom. This still may not work 100% of the time.
Performers must either leave computer audio in Zoom or both mute their Zoom mic AND ALSO mute their Zoom computer speakers. It is much easier to leave computer audio.
All Non-Performing Participants should mute their Zoom microphone unless they want to speak. Any unmuted sound they make is broadcast to all performers and Non-Performing Participants.
The Performer or Non-Performing Participant who also acts as Broadcast Hub MUST:
Turn on original sound in Zoom, and in the audio settings menu, disable automatic volume control. In the advanced audio settings disable echo cancellation, turn on high fidelity music mode, and turn on stereo audio.
In SoundJack, mute the self-monitoring fader in the left settings column
Create the five Loopback cards to connect SoundJack and Zoom while routing their microphone into the input of each app as outlined below.
Specific connections by participant type
NOTE: If your workflow includes recording or broadcasting through Zoom, whatever user does so must turn on “original sound,” and raise the advanced audio settings as though they were the Broadcast hub. Otherwise, you risk recording at a low audio quality.
Performers
connect to Zoom with video only (leave computer audio or do not join it in the first place),
connect to all performers on SoundJack,
connect to the Broadcast Hub on SoundJack.
Non-Performing Participants
join Zoom with headphones, with or without original sound enabled.
Performer or Non-Performing Participant who also acts as Broadcast Hub
connect to performers on SoundJack,
join Zoom call with computer audio, with original sound and the highest audio quality setting on (see below). Note you may have to scroll down to see the “advanced” link.
set input and output (microphone and speakers) in SoundJack and Zoom as explained below.
whoever is host of the Zoom call, right click on video feeds of performers (and possibly of the teacher too) and click “spotlight.” This ensures that all Non-Performing Participants see the performers on their screen. Spotlight as many video feeds as you like. Remove the spotlight if you would like to return to a group discussion setting.
Setting up the Broadcast Hub
Audio setup
Close all applications, including any background Cloud Sync apps or other processes.
Open Loopback
Create a new virtual card (lower left-hand corner of window). Name sound card “Talkback Mic.” By default, there should be a “Pass Thru” source to two output channels, which you may select and delete. Click the plus icon to the right of “sources” and add your microphone. Here the mono MacBook built in microphone is selected and mapped to both channel 1 & 2. This could also be an external audio interface. Generally speaking, if you have a single microphone it is best practice to map the mono stream to both the left and right output channels.
You will control your microphone but toggling the “Talkback Mic” virtual card on and off in the left column. This will turn it on and off in any other virtual card you add it to as an input.
Create a second virtual card and name it “Into SJ.” By default, there should be a “Pass Thru” source to two output channels which you may delete. Click the plus icon to the right of “sources” and add the virtual card named, “Talkback Mic.” With Zoom running, add the zoom.us app as a source. Expand the options and uncheck “mute when capturing
Create a third virtual card and name it “Into Zoom.” By default, there should be a “Pass Thru” source to two output channels which you may delete. Click the plus icon to the right of “sources” and add the virtual card named, “Talkback Mic.” With the SoundJack app (current version is SJC201112) running, add the SJC app as a source. Expand the options and uncheck “mute when capturing.”
Create a fourth virtual card and name it “Out of SJ.” By default, there should be a “Pass Thru” source to two output channels which you leave in place. Click the plus icon to the right of “monitors” and add your audio interface. Here the external headphone of the MacBook is selected.
Create a fifth virtual card and name it “Out of Zoom.” By default, there should be a “Pass Thru” source to two output channels which you leave in place. Click the plus icon to the right of “monitors” and add your audio interface. Here the external headphone of the MacBook is selected.
Open Zoom and either start/join meeting
Choose “Into Zoom” for Microphone and “Out of Zoom” for Speakers
Verify SJC app is running
Open SoundJack.eu in a single Chrome browser
Login and go to Stage. Select Input as “Into SJ” and Output as “Out of SJ.”
Set SoundJack sample buffer and network buffer each to 512, unless your computer is strong enough to set the buffers low enough for a low latency connection to the Performers. Set the audio codec to OPUS 192, and mute fader under VU meter. If Zoom participants hear an echo, make sure this is muted. Set the send channels based on how your performers are sending their streams. If they both send channels: 1 (mono), leave this at send channels: 1 (mono). If one sends stereo, switch to send channels: 2 (stereo). If you hear one or more of the performers in only one ear have them switch to send channels: 2 (dual mono). Once a SoundJack participant switches away from send channels: 1 (mono), you may have to refresh the stage and reconnect to one another to return the call to send channels: 1 (mono). Otherwise, you will hear the mono Performer in just one ear.
Connect Broadcast Hub to Performers on the Stage. Unless you want to participate as a Performer, your goal is not to have a low latency connection with the Performers. Your goal is to have a rock-solid connection where the latencies to each performer are roughly the same, within 5-10ms. Performers optimize their connection to each other with the lowest settings that work. They may raise their jitter buffers on you, but I would suggest that they set it to the same number (e.g. everyone jitter buffers you at 10). Raise jitter buffer per performer as high as necessary on the Broadcast Hub. Try to match the latencies using the jitter buffers. If you are used to setting these as low as possible as a SoundJack participant, you may find yourself setting it well above 10. If each performer is sending at a different network buffer, these jitter buffers may be wildly different. Depending on the stability of each performer’s Internet connection, you may need to have them raise their network buffer to 256 (especially if they have Xfinity, Starry, or another non-fiberoptic internet plan). If they do this, make sure that they each lower their jitter buffers on each other to regain the fastest connection possible between them. Start with both performers’ volume faders all the way to the right. Adjust their relative volume if need be.
Reminder: Performers must leave computer audio in Zoom. It is not enough to mute the microphone.
Performers should sing/play a loud, high pitch from their piece to check gain levels before beginning the performance. Try to send as loud a signal as possible without distorting.
At this point, audio from SoundJack should flow to participants on Zoom, and audio from Zoom to the Performers on SoundJack. The Participant managing the Broadcast Hub should be able to send their audio to both SoundJack and Zoom. Best practice is for Non-Performing Participants to mute themselves when not contributing. If you run into issues, please consult Appendix A: HELP! Something Terrible is Happening. To avoid issues in the first place, pleases read through Appendix B: Session Checklist.
Appendix A: HELP! Something Terrible is Happening
Common issues
Issues addressed below are divided into the following categories. Beyond the scope of this article are the finer points of optimizing a SoundJack connection. NOTE: If you refresh the SoundJack stage or disconnect from a SoundJack user, or leave and rejoin Zoom, settings will return to defaults and may need to be reset (e.g self loopback fader in SoundJack unmutes, SoundJack user’s jitter buffer resets to 4, Zoom audio mute/unmute).
· Echoes
· Someone’s Audio is Missing
· Audio Quality Issues
| Issue | Likely Cause | Solution | ||
|---|---|---|---|---|
| Echoes | ||||
| Echo of self heard by SoundJack Performer through Zoom device | Forgot to leave computer audio on Zoom device | Leave computer audio, or both mute Zoom device microphone and also mute Zoom device speaker | ||
| Echo of self heard in Performer’s SoundJack headphones | The self-monitoring fader in Performer’s SoundJack Stage is unmuted and turned up | Mute the self-monitoring fader in Performer’s SoundJack Stage (below VU meter in left column) | ||
| One of the Non-Performing Participants is not using headphones and is unmuted | Host mutes the offending Non-Performing Participant in Zoom and messages them to get headphones and stay muted when not contributing | |||
| General echoes heard in Performer’s SoundJack headphones and Zoom Non-Performing Participants’ headphones | Some Non-Performing Participant is not using headphones and has echo cancellation turned off/original sound turned on, and their microphone unmuted. And/or performer forgot to leave computer audio in the Zoom device | Confirm that all Non-Performing Participants have headphones. If no one volunteers as being the issued, Zoom host mutes all Non-Performing Participants and unmutes one by one until the echo returns. Have that Participant confirm they have headphones and that they are selected as the speaker in Zoom | ||
| Echo of Zoom Non-Performing Participant heard by all Zoom Non-Performing Participants | Assuming All other Zoom Non-Performing Participants are muted, and everyone hears an echo of the one Non-Performing Participant speaking, most likely cause is a Performer forgot to leave computer audio in their Zoom device | Have Performer leave Zoom computer audio | ||
| Or, the self-monitoring fader in Broadcast Hub’s SoundJack Stage (below VU meter in left column) needs to be muted | Mute the self-monitoring fader in Broadcast Hub’s SoundJack Stage (below VU meter in left column) | |||
| Echo heard only by one (or a few) Zoom Non-Performing Participants | This most likely means that the Zoom Non-Performing Participant hearing the echo is both wearing headphones with an inline microphone, and also has original sound turned on in Zoom with the echo cancellation turned off | Non-Performing Participant who hears the echo replace headphones or turn off original sound in Zoom | ||
| Someone’s Audio is Missing | ||||
| Missing audio from Performer to Non-Performing Participant or vice versa | Zoom and SoundJack microphone/speaker (audio input/output) are incorrectly set | Set the input and output audio sources correctly per Audio setup above | ||
| Loopback virtual audio card master volume is turned down or pass-thru tile is turned off | Verify that both Loopback virtual audio cards master volumes are 100% | |||
| Missing audio from a Zoon Non-Performing Participant | They are most likely muted or have an issue with their microphone | Host invite them to unmute, and/or troubleshoot their microphone | ||
| Missing audio from a Performer when Loopback virtual audio cards and input/output settings in Zoom and SoundJack are all correct | If you do not hear one of the performers and do have a displayed latency for that SoundJack connection on the Broadcast Hub, there is most likely an issue with the Performer’s audio signal chain | Verify that when the Performer makes sound into their microphone, the needle moves on their user entry in the Broadcast Hub. If it does, check that their volume fader is not too low in their user entry on the Broadcast Hub SoundJack Stage. If it does not move, have them check their audio signal chain, including whether 48V+ (phantom power) is turned on on their audio interface, whether they have correctly connected their microphone to the audio interface, and whether they have turned their microphone input volume (gain) up high enough. | ||
| If you do not hear one of the performers and do not have a displayed latency for that SoundJack connection on the Broadcast Hub, there is an issue with their SoundJack connection | Easiest fix is to connect to the Performer on the Broadcast Hub’s SoundJack Stage. Verify that you have connected to them by pressing the play button to the right of their name in the user entry list on the Broadcast Hub Stage, and that they have accepted your invitation. If you see TRYING or ONE-WAY instead of a latency, the most likely explanation is that this user has not successfully set up port forwarding on their router. Or, you have not successfully set up port forwarding for your Broadcast Hub. Verify this by hovering the mouse over their green info circle on their Stage entry. (111) means they are port forwarded. Any other three-digit code means they are not. | |||
| Performer has a SoundJack connection to other Performers or the Broadcast Hub that drops | This may happen occasionally, but if it happens with any regularity, this is likely an issue with your audio hardware. | If you had a successful connection on SoundJack that later drops, especially if this happens repeatedly, please contact Dr. Howell immediately so that he can troubleshoot your set up. Include the name of your Internet service provider, the type of computer you are using to connect to SoundJack (Fastmusic Box, MacOS, Windows), whether that computer is plugged directly into your router via Ethernet, what type of audio interface you have, and whether you use a powered USB hub to connect that audio interface to the computer or fast music box. | ||
| Audio Quality Issues | ||||
| One of the Performers is distorting | If a performer distorts, it is most likely at the microphone volume input knob (gain) of the Performer’s audio interface. | Verify that the microphone volume input knob(gain) is not peaking on the Performer’s audio interface. | ||
| If performers are both at the edge of distorting their audio interfaces and their faders are all the way to the right in the Broadcast Hub user list, it is possible that together they will distort. | The Broadcast Hub will need to turn the Performers’ faders down a little. If this were the case, you would see the meter in the loopback audio card named Zoom In — SJ Out peaking into red on the pass thru tile. | |||
| One or more of the Performers are too quiet | The Performer’s microphone volume input knob (gain) on their audio interface is set too low | Have the Performer execute a high/loud sustained pitch from their piece and raise their microphone volume input knob (gain) until they are just short of peaking their audio interfacee | ||
| The Performer’s volume fader on the Broadcast Hub’s SoundJack Stage is set too low. | Best practice is to start with all Performers’ volume faders on the Broadcast Hub’s SoundJack Stage at 100% (all the way to the right) | |||
| The Performers’ audio stream sounds processed, low quality, or the volume changes in response to how loud they are | The Broadcast Hub needs to “turn on original sound” and the other high-quality audio settings in Zoom | Verify that original sound is on in Zoom on the Broadcast Hub. Also go into the audio settings and verify that automatic volume control is unchecked, and on the advanced page that echo cancellation is disabled, high fidelity audio enabled, and stereo audio enabled. | ||
| The Performers’ audio stream sounds garbled (like a burbling underwater sound) or exhibits pops or clicks to Zoom Non-Performing Participants | Incoming SoundJack stream received by the Broadcast Hub is insufficiently buffered. | Verify that Performers are sending audio using the OPUS 192kbps Codec. Raise jitter buffers on the Performers’ user entries on the Broadcast Hub’s Stage. If this is not enough to address the sound (and obvious issues such as a Performer being on Wi-Fi rather than Ethernet have been ruled out), ask the Performer to raise their network buffer one setting. Typically, Fios users can send network buffer 64 or 128. Xfinity and Starry users tend to have to send at network buffer 256 to overcome network traffic. | ||
| The Performers’ audio stream sounds terrible and it previously sounded great at these buffer settings | The Broadcast Hub is most likely on Wi-Fi | Make sure that the Broadcast Hub disconnects from the Wi-Fi network, that the Ethernet cable is connected, and that you refresh the SoundJack. Stage. If you accidentally port forwarded the local IP address of your Wi-Fi network interface, you will need to correct that in your router. | ||
| I hear a Performer in only one ear (left or right, but not both) | One of the Performers or the Broadcast Hub is connected to SoundJack with send channels: 2, either dual mono or stereo | Switch everyone on SoundJack to send channels: 1 (mono), unless one of the participants is actually sending a stereo audio stream. In that case, switch the mono participants to send channels: 2 (dual mono). If one of the participants | ||
| I recorded through Zoom, but it sounds compressed | The Zoom computer that is recording likely did not turn on Zoom's "original sound." | Turn on "original sound" with highest audio quality settings enabled. |
Appendix B: Session Checklist
Broadcast Hub
o On Broadcast Hub MacOS computer, launch Loopback, SJC app, Zoom, and a Chrome window for SoundJack.eu. Close any other apps, including Cloud Sync background processes
o Verify that Zoom original sound with highest quality settings is enabled
o Verify that input/output settings are correct in Zoom and on SoundJack.eu Stage.
o Mute self-monitoring feed on SoundJack Stage
o Set sample and network buffers to each 512, and audio codec to OPUS 192kbps on SoundJack.eu Stage
o Make performers leave computer audio on Zoom
o Connect to Performers on SoundJack.eu Stage. Raise jitter buffer on each to maximize connection quality and match their latencies within 5-10ms.
o If unable to make a stable connection with a high jitter buffer, have Performer(s) raise their network buffer one setting
o Join Zoom on a second device using headphones to monitor and/or participate in the class. Mute Zoom audio unless you wish everyone on the call to hear you
o Spotlight (or have Zoom host spotlight) the performers
Performers
o Join Zoom without joining computer audio (or leave computer audio if already joined)
o Run SoundJack per your setup and navigate to the SoundJack.eu Stage
o Connect to other Performers and Broadcast Hub
o Set audio levels and buffers as you normally would to minimize latency, set Opus Codec to 192
o Set jitter buffer on Broadcast Hub user as high as you like. This controls the latency of the incoming Zoom audio from the Non-Performing Participants. There is no need to set this low as the latency will be high to start.
Non-Performing Participants
o Join Zoom on a device using headphones
o Only unmute microphone if you want everyone on the call to hear you
o If using headphones with a built-in microphone, leave Zoom’s original sound off
Appendix C: Can I do Advanced Things?
Yes. Yes, you really can.
1. If the performers are in a nice space, consider using a stereo microphone. All SoundJack connections would then have to be set to send channels: 2 (stereo).
2. Consider a real time YouTube/Facebook/OBS stream through Zoom, or use an account that permits a webinar format for a performance.
3. Consider recording the Zoom video as the class happens.
4. Consider routing the sound out of SoundJack through a DAW to master the audio in real time before passing it along to Zoom. Add audio latency at this step to best match the Zoom video delay.
5. If you have multiple performers and a strong enough hub computer, consider creating a multi-channel Loopback virtual card to separately route each incoming audio stream in SoundJack to a separate track in a DAW.
6. Use the pass thru on/off switch in the Zoom Out—SJ In virtual card to kill all sound from Zoom participants reaching performers (extra control over misbehaving Non-Performing Participants).
