Doable:

• small groups playing together between home locations (say < 12 members)
• concert broadcast via Youtube Live, Vimeo, Zoom
• linux, mac, windows, BSD laptops and desktops (also Raspberry Pi)
• own choice of audio interfaces with mics, etc.

Difficult:

• larger groups (but we haven't tried)
• wifi (requires ethernet wire from home router)
• built-in sound on laptops

Impossible:

• syncronized video (but try LOLA for that)
• conducted ensembles
• mobile devices
• hosted wine and cheese receptions

Plan for this evening:

• terminology
• live demo
• building groups
• home stations
• Q&A
• hands-on

latency is the time delay between cause and effect -- used interchangeably

an internet host is a computer on the network -- used interchangeably

a server listens for a client to connect to it -- different jacktrip modes

each jacktrip instance runs a transmitter and receiver -- bidirectional

my local host and a remote peer host -- either can run in either jacktrip mode

our IETF -- owes everything to

ietf.org

Audio quality:

• buffer size (affects latency)
• gain
• feedback
• number of channels
• self-monitoring
• muting other audio applications (Zoom)
• sharing audio signal between applications (audacity)
• running Zoom on a second host (mobile or laptop)

Network quality:

• physical distance and number of intermediate router hops in path (affects latency)
• playback queue (affects latency)
• jitter vs. packet loss
• redundancy for forward error correction
• wavetable vs. zeroes (very "backwards" error concealment)
• better error concealment (under construction)
• network peering locations can be a surprise
• last mile (fiber, cable, vdsl, microwave, 5G)
• wifi inadequate but useful for basic testing
• choke points, competing applications on the same local host and local network, internet weather
• venues, when we get to use them again

violin and cello demo

acoustic instruments with air mics

Alex Goldberg and Marina Bosi, Redwood City

talkback channel, in this case it's Zoom

153b groups during this past Spring Quarter

• jazz sextet+
• new music Bay Area
• Stanford new music ensemble
• new music quartets (JACK, Kronos)
• wind quintet
• 153b jam band

the paths forward for local ensembles

equip musicians with their choice of devices
set up local servers

• DIY software installs (like we know)
• nearby hardware-based servers (like we know)
• Raspberry Pi + soundcard (plug+play with interface)
• nearby cloud servers
• ...and DIY Raspberry Pi systems (mouse, keyboard, monitor)

all open source
Raspberry Pi solutions and cloud-based services are in the works and will be obtainable from third parties

Monday, April 6

• introduction
• installation
• test machine: 171.64.197.160
• settings:
  srate = 48kHz, buffer size = 1024, channels = 1
• command:
  ./jacktrip -C 171.64.197.160 -n1

Before going on the network, do an audio test first:

• start qjackctl
• in the connection window, connect mic to speakers or headphones
• verify that there is signal
• tap directly on the mic to be sure it's the right mic (not a built-in laptop mic)
• click on disconnect
• verify that the signal goes away (otherwise it's not qjackctl that's created the connection and most likely it's a direct sound monitoring path in your sound card)

Which jacktrip mode to run:

• simple peer-to-peer server
  ./jacktrip -s
• simple peer-to-peer client
  ./jacktrip -c <IP Address or Name of server>
• hub (group) server
  ./jacktrip -S
• client of hub (group) server
  ./jacktrip -C <IP Address of server>
(-C mode doesn't recognize name, yet)

Connect to jacktrip loopback server:

• command:
  ./jacktrip -C 171.64.197.160 -n1
• play or sing a sustained tone
• listen for dropouts
• watch for "waited too long" messages
• too many dropouts?
• increase the input queue by adding -q<N>, for example, a queue of 8 packets (default = 4)
• command with queue of 8 packets:
  ./jacktrip -C 171.64.197.160 -n1 -q8

Things that prevent connection

• mismatch between local and peer sample rate
  --restart qjackctl with same sample rate as peer
• mismatch between local and peer buffer size
  --restart qjackctl with same buffer size as peer, also called frames / period
• "waiting for peer" forever
  usually this is because computer firewall or router firewall is blocking incoming data

Matt's explanation of the all those "jacks".

jackd is the actual Jack (jack audio connection kit process -- a daemon)
The "d" stands for daemon
It runs in the background letting other programs on the computer send and receive audio to each other and to whatever audio hardware jack is connected to.

jackd can be started from the command line but is more often launched from JackPilot or qjackctl

JackPilot is a graphical front-end to Jack.
It’s a program that opens a window you can click on, has a "Preferences" window, etc.
JackPilot’s preferences window is where you can:
- select which audio interface you want Jack to use
- select the Sample Rate and Buffer Size that Jack will use
- configure JackRouter
You must set all such preferences before starting Jack.
You can start Jack by clicking "Start" in the main JackPilot window. (On OSX this is the recommended way to start Jack)
On OSX with a normal Jack installation, the JackPilot program lives in
/Applications/Jack, that is, the "Jack" subfolder of the main Applications folder.

Matt's explanation (cont'd)
qjackctl is another graphical front-end to Jack.
"qjackctl" is pronounced "cue jack control" (though Mark Applebaum suggests making it rhyme with "pterodactyl") Its main window is (confusingly) titled "JACK Audio Connection Kit"

On OSX with a normal Jack installation, the qjackctl program lives in
/Applications/Jack, that is, the "Jack" subfolder of the main Applications folder.

The yellow word at the center top of the window will be "Active" if (qjackctl understands that) jack is running, or "Inactive" or "Stopped" otherwise
Please ignore all the green writing (which has to do with MIDI, not audio)

The "preferences" for qjackctl are in the "Setup" window, which you open and close by clicking the "Setup…" button on the main window

The most useful part of qjackctl is the "Connections" window, which you open and close by clicking the "Connect" button on the main window
The connections window shows all the jack-enabled programs currently running through Jack. It lets you connect any output of any program to any input of any program.

On OSX it appears that you cannot start Jack from qjackctl. JackRouter is part of Jack on OSX that lets non-jack-enabled programs (for example iTunes, QuickTime Player, Chrome) connect their audio to Jack.

latency is the time delay between cause and effect -- used interchangeably

an internet host is a computer on the network -- used interchangeably

a server listens for a client to connect to it -- different jacktrip modes

each jacktrip instance runs a transmitter and receiver -- bidirectional

my local host and a remote peer host -- either can run in either jacktrip mode

our IETF -- owes everything to

ietf.org

Audio quality:

• buffer size (affects latency)
• gain
• feedback
• number of channels
• self-monitoring
• muting other audio applications (Zoom)
• sharing audio signal between applications (audacity)
• running Zoom on a second host (mobile or laptop)

Network quality:

• physical distance and number of intermediate router hops in path (affects latency)
• playback queue (affects latency)
• jitter vs. packet loss
• redundancy for forward error correction
• wavetable vs. zeroes (very "backwards" error concealment)
• better error concealment (under construction)
• network peering locations can be a surprise
• last mile (fiber, cable, vdsl, microwave, 5G)
• wifi inadequate but useful for basic testing
• choke points, competing applications on the same local host and local network, internet weather
• venues, when we get to use them again

cello demo

acoustic cello with air mic

electric cello

talkback channel, in this case it's Zoom

breakout rooms here we go again, 5 this time



171.64.197.160

171.64.197.169

171.64.197.156

171.64.197.166

171.64.197.207

adopt-a-server

public IP address for ensemble members to connect to

start jackd from command line and jacktrip server in loopback (or other audio patch) mode

use tmux to be able to detach job and leave it running 24/7

basic manual operation
(no watchdog process or email alerts from server)

CCRMA machines are available

CCRMA account required to login to CCRMA machines

Ensemble info :

• which instruments in the ensemble
• audio equipment needed
• computers needed
• which operating systems will be used
• (email to cc@ccrma.stanford.edu)

jacktrip molecules and atoms

molecules:
we've been practicing hub mode (-S / -C)

which is made out of multiple atoms:
simple two-way, connections (-s / -c)

Ensemble sound checks

• get the group talking together on Zoom, jitsi, skype or the like
• have each member test their local audio loopback:
  qjackctl connect capture -> playback
• tech lead person start group server in full mix mode:
  ./jacktrip -S -p4
• have each member test their network audio:
  ./jacktrip -C <server_IP_address> -n1
• when everyone can hear everyone else well, end the connections
• tech lead person restart group server in FOFI mode:
  ./jacktrip -S -p2
• then everyone rejoin and take it from there

Server stress test

• test your local audio loopback:
  qjackctl connect capture -> playback
• test your network with loopback server:
  ./jacktrip -C 171.64.197.160 -n1
• join the horde, crash the server:
  ./jacktrip -C 171.64.197.158 -n1

jacktrip two-way, bidirectional audio connection

• server and client
• start jack audio on both sides
• start the server first
• server:
  ./jacktrip -s -n1
• client:
  ./jacktrip -c <server_IP_address> -n1
• or:
  ./jacktrip -c <server_host_name> -n1

server must have port open

• incoming UDP port 4464 (is default)
• select a different port with "-o" port offset
• server:
  ./jacktrip -s -n1 -o10 (uses UDP port 4474)
• client:
  ./jacktrip -c <server_IP_address> -n1 -o10

ping

• ping www.yahoo.com
• ping 171.64.197.1
• might not respond (dead or wrong name, wrong IP address)
• might not want to respond (policy reasons, for example no CCRMA machines will answer)

traceroute

• traceroute www.yahoo.com
• shows path through intervening routers
• pinging them in succession
• prints * * * if no response

iperf

• server and client (same style as jacktrip)
• sends a test batch of data from client to server
• server:
  iperf -u -s -p 4464
• client:
  iperf -u -c <server_IP_address> -p 4464
• I use iperf2 but iperf3 exists

terminology, names

• jack server (audio)
• hub server (a host for hub mode)
• peer-to-peer server (starts a two-way)

jack operation

• where settings are set
• only one jackd at a time
• use "killall jackd" command
• doesn’t have to be issued from the same directory, and should result in
  "jackd: no process found" once there's no longer a jackd

OS installation

• a file permissions bug in the current macOS installer
• unidentified developer, package cannot be opened, or installation is potential malware (Go to System Preferences / Security and Privacy)
• Windows security settings; Allow an app through firewall.
• Windows Peer to Peer Collaboration Foundation
• curious error messages that need explaining: MMCSS API not used

server management

• accidental root login will lock out their next attempts, remote CCRMA users to use their account name explicitly
• need to initiate the ssh -Y from an X server (such as XQuartz on macOS)
• audio permissions on server for remote users
• script timings vs. jack (sometimes need to add a small amount of sleep)

versions

jacktrip versions (-v) -- should be latest, V1.2

qjackctl changed and there are two versions running "Connections" is now labeled "Graph" instead but you can change it back

not all dongles

details that get in the way

• selection of mode (particularly "-C" vs. "-c")
• audio settings on all machines must match, particularly sample rate
• running only 1 channel (using only one side of headphones)
• builtin mic / builtin speaker can squeal with loopback insanely
• using a disabled command argument, the software should print a warning (-S -n)

good surprises!

• running associated audio applications can work
• there are some unexpected and working audio interfaces (USB microphones, guitar amps)
• we are in a rare position (worldwide) having a flock of physical servers to use (others are using cloud and paying)

good and not a surprise!

• many 153b jacktrip saints!
  especially Matt, Synthia, Dave, Bonnie, Nick and all who are helping others

to discover through use

• home ISP service can degrade
• push the limits on number of channels
• how low can you go, latency-wise

"JackTrip in Zoom (Webinar)" -- the 10am

"They are running JackTrip, routed into Zoom. Thomas was able to get into their university facilities and bring the drumset player Carl. Trond has a network arts studio he built out at home. He was able to coordinate with the local public internet provider to optimize his routing and configurations. So that's how they are running JackTrip.

They have the whole JackTrip connection in one computer, they are slightly delaying the signal in order to line it up with the Zoom video latency, adding slight reverb, and then outputting into a Zoom computer.

I have a "Webinar" room in Zoom now, so the viewer only sees the artists. The audience is listed as attendees and only communicates via the text chat. It is a different presence but it's a significant improvement to the look of the event. Still would prefer to see small visual icons of the audience on the bottom of the screen, maybe this will be a feature in the future or in a different platform that emerges.

The dress rehearsal yesterday was impressive. This is the closest I have experienced to a real "virtual venue". It's much better sound with JackTrip and the "Webinar" room looks good. Adding the slight delay to JackTrip lines up the visuals. This felt exciting. "

"jacktrip in Youtube and Vimeo Live" -- the 1pm

The 'Quarantine Sessions' are realized using free and open source technologies, which can be easily adopted by anyone:

jacktrip (audio)

jitsi (video)

OBS (streaming)

network fiber laces the world

watch this now

Inside the Beach House

153b concert? For end-of-term?

• who's already planning something?
• bring some of the current groups to the "stage"
• form new groups

ensemble query followup in our group

• Mac Kenley, trombonist
• Lesley Roberston, violist
• Jerry McBride, wind quintet

ensemble query followup, new groups

• Golden Gate Men's Chorus
• San Francisco Early Music Society
• Paul DeMarinis, Laetitia Sonami, Sue Costabile, event at SAIC (Chicago)
• Marie-Louise Catsalis (work with music theater students)

network fiber laces the world

watch this now

Inside the Beach House

new upgrade version of jacktrip

• -C (connect to server by name or IP address)
• -Sz (hub mode with zeroes)

testing it

• today both cmn9.stanford.edu and
  cm-jam.stanford.edu are servers running the new version
• number of clients is limited to virtual cores still

versions

• win10 (but broke -C with IP address)
• linux (fedora, ubuntu?)
• macOS (mojave, catalina)

Here's a head scratcher:

Single jacktrips were originally created to do 3-way audio patches over the net
a-b, b-c, c-a

Hub server mode is a centralized relay which spawns on demand,
a-s, b-s, c-s -- let's call that server"sa."

In the past couple weeks "sa" has started to get too big to host on a single machine. We need to do fully connected
sa-sb, sb-sc, sc-sa

I've only faked it using independent single tie points, so far
sa-t-sb

and that's a pain, it works but seems like it won't scale.

now some live testing with up to 40 participants split into four groups

• I've started cm-jam, cmn5, cmn9, cmn13 with -Sz
and this needs some coordination
• 16 in first group, -C cm-jam.stanford.edu (171.64.197.121)
• 8 in second group, -C cmn5.stanford.edu (171.64.197.154)
• 8 in third group, -C cmn9.stanford.edu (171.64.197.158)
• 8 in fourth group, -C cmn13.stanford.edu (171.64.197.162)

exercise in latency testing, how low can you go?

six servers are running different frames per period (aka Jack buffer size and packet size)
FPP = 32, 64..., 512, 1024

• cmn5.stanford.edu (32) (171.64.197.154)
• cmn13.stanford.edu (64) (171.64.197.162)
• cmn14.stanford.edu (128) (171.64.197.163)
• cmn15.stanford.edu (256) (171.64.197.164)
• cmn25.stanford.edu (512) (171.64.197.174)
• cmn26.stanford.edu (1024) (171.64.197.175)

for example, set audio to 48000 / 1024 and do
jacktrip -C cmn26.stanford.edu (or 171.64.197.175)