X API update

Attempts to use the X API (formerly Twitter) for projects with Max/MSP have been disappointing at best. Most of the API is behind a paywall now.  The cost is $5000 per month. to implement streaming API used in projects like this:  https://reactivemusic.net/?p=5786

The free tier only allows basic tweeting and user lookup. Search is not available.

I was able to find only one node example that actually worked in the free tier. By “Coding with Ado”. The code requests a token from X, and then you enter a timestamped pin number to continue. Making it worthless for programs and bots. https://youtu.be/G5ZW5j5cwHk?si=vbAtGa0bQ3T_tga9

A local copy of the source code for this is in tkzic/nodetweet3/index.js

Other options

Another option with X, is to use a service like Socialdata. https://socialdata.tools/

There service sits in the middle to handle X API calls. You are charged by the number of calls. It doesn’t offer streaming either, but you can simulate it by calling a search every few seconds.

Other social media options

There are API’s for other social sites like facebook, instagram, tiktok, etc.,

MBTA Boston train map

This post describes an update of a previous version. The old version can be found here: https://reactivemusic.net/?p=20329

Moving markers

In the previous version, all of the markers for each train line were deleted and redrawn in a group at the polling interval. In this version the train markers move to their new location when the data is polled.

The map is drawn using Leaflet. The moving marker library is from Ivan Sanchez https://www.npmjs.com/package/leaflet.marker.slideto

The project uses the MBTA JSON API, to query vehicle data for each train line. the geo coordinates of the trains are sent via websockets to the client map page.

This project is a work in progress and not available yet.


node server: internetsensors/mbtanode2/index.html

html map client: internetsensors/mbtanode2/mbtatrain2.html


// to run, type node index.js at a command line.
// then open a web browser to:
// type 'go' into the text box below the map, and press 'send' button
// in a few seconds the train markers will magically appear

Max/MSP text to Morse code generator

work in progress. not published.

I needed a text to morse code generator in Max for the Twitter streaming map project. There was an ancient one that used [mxj] but its kind of a pain to use that object. I thought it can’t be that difficult to write one? I didn’t really have any idea where to start. Something about the blank Max patch causes brain activity? I went through about 5 different approaches. Eventually came up with this pattern thing, from thinking about the lighted buttons on the tr-808 drum machine.

For example, the letter A is . _ (dot dash)

morse code has rules for spacing:

dot = 1
space between tones = 1
dash = 3
space between letters = 3
space between words = 7

If you think of a drum machine pattern, the pattern for letter A would be: 1 0 1 1 1 0 0 0  (with the 3 trailing 0’s for letter spacing)

I made a [coll] with all the letter patterns indexed by ascii codes.

Then just concatenate letter patterns, for a given block of text,  together into one big list and run it through [zl.nth] clocked by a [metro] and [counter]. the ones and zero’s turn an oscillator on and off.

local file: tkzic/internetsensors/twitter-stream2/morse5.maxpat

Milford Graves Experiment

Milford Graves was one of my all time favorite musicians. His approach to percussion, and music generally, was unique in a way that defies explanation.

I sampled a bunch of clips of his drumming into Ableton live and then experimented with the Buffer Shuffler 2.0 device to see if I could randomize small slices, ie., several seconds each, of longer samples – without losing the “texture” of the original recordings.

Here is an example of what it sounds like:

This video shows a clip from David Murray’s “Real Deal” running through Buffer Shuffler using slices only about 2-3 seconds in length. The slicing rate is just arbitrary, since there is no warping or specific clock pulse.

Local files: tkzic/aardvark/milfordgraves1 project/milfordgraves1a.als

Hamlib C programming example on Mac OS

Hamlib provides a standardized computer interface for amateur radios.

I was able to get it to run in a C program on Mac OS Ventura.


Install Hamlib using homebrew. ie,., brew install hamlib.

Download this sample C test code – testrig.c – from https://hamlib.sourceforge.net/manuals/1.2.15/_2tests_2testrig_8c-example.html or https://github.com/Hamlib/Hamlib/blob/master/tests/testrig.c

Change the SERIAL_PORT constant to the actual port name. Change the baud rate.

Lookup the hamlib code for your radio. https://github.com/Hamlib/Hamlib/wiki/Supported-Radios

For example, for the Elecraft K3, the code is 2043.

compile using this command:

gcc testrig.c -I /opt/homebrew/include -L /opt/homebrew/lib -l hamlib -o testrig

Type this to run the program:

./testrig 2043

Assuming 2043 is the rig number. If all is working, the program will set a bunch of stuff on your radio, changing frequency, mode, etc.,

Local files: tkzic/chatgpt/radio/ctest.c

notes: link to instructions for compiling hamlib manually: https://github.com/Hamlib/Hamlib/blob/master/README.osx

Using Web Serial API for Radio CAT interface

Work in progress…

An html example that sends and receives CAT commands with an Elecraft K4 connected to the serial port of the machine running the web browser.

The file was built using examples from this article by Francois Beaufort. https://developer.chrome.com/docs/capabilities/serial It’s an excellent resource for Web Serial.

The html file for this project is here: http://www.pr0jex.com/serial/index.html

But it won’t run from that server. It only runs locally.


Download the index.html file from the link above. start a local web server, eg., “npx http-server” and enter the server address into a Chrome browser.

When you press connect, the browser will prompt you to select a serial port for the radio.  On my computer the K4 serial ports appear something like: cu2.usbserial-21100. There are 2 ports. Select either one.

Then press read. If you spin the dial on the K4, and it is autoinfo mode, you should see CAT commands in the read window.

enter a CAT command in the write window and press the write button. It is preloaded with “fa7;” which sets frequency to 7 MHz.

Press the disconnect button to end your session.

local files tkzic/webusb/serial2/index.html


Virtual serial port pairs in Mac OSx

I was unable to find any apps to create virtual serial ports for later versions of Mac OSx eg., Catalina.

There is a partial solution using the linux socat utility. It will create functioning vsp’s but the ports will not be detected by most apps, like Max/MSP.  I tried setting a symlink to files in /dev using tty. and cu. prefixes. eg., /dev/tty.x1. But apps that look for serial ports still couldn’t detect the vsp’s.


  1. download and install socat using macports or brew. eg., “sudo port install socat”
  2. Disable SIP (system integrity protection). In Catalina, reboot holding cmd+r. Then type: “csrutil disable” into a terminal window. Reboot – Note: you probably don’t need to do this if you aren’t setting up a link in /dev – which so far doesn’t work anyway
  3. Run one of the following commands:

socat -d -d pty,raw,echo=0 pty,raw,echo=0

sudo socat -d -d pty,link=/dev/tty.x0,raw,echo=0,user=tkzic,group=staff pty,link=/dev/tty.x1,raw,echo=0,user=tkzic,group=staff

What works and what doesn’t

After setting up the ports, you can send data in one port and out the other, for example, type the following into 2 different terminal windows.

cat /dev/ttys004

echo “Hello World” > /dev/cu.x1

This works great. But, so far, using sym links – the ports don’t show up in any app that accesses serial ports. Still working on this…

Using socat you can also setup a serial/tcp pair – this may be a solution for some projects.


Sonification of Mass Ave buses, from Nubian to Harvard.

Updated for Max8 and Catalina

This patch requests data from MBTA API to get the current location of buses – using the Max js object. Latitude and Longitude data is mapped to oscillator pitch. Data is polled every 10 seconds, but it seems like the results might be more interesting to poll at a slower rate, because the updates don’t seem that frequent. And buses tend to stop a lot.

Original project link from 2014: https://reactivemusic.net/?p=17524

MBTA developer website: https://www.mbta.com/developers

This project uses version 3 of the API. There are quality issues with the realtime data. For example, there are bus stops not associated with the route. The direction_id and stop_sequence data from the buses is often wrong. Also, buses that are not in service are not removed from the vehicle list or indicated as such.

The patch uses a [multislider] object to graph the position of the buses along the route – but due to the data problems described above, the positions don’t always reflect the current latitude/longitude coordinates or the bus stop name.



folder: mbta


  • mbta.maxpat
  • mbta.js
  • poly-oscillator.maxpat

You will need  to replace the API key in the message object at the top of the patch with your own key. Or you can probably just remove it. The key distributed with the patch is fake. You can request your own developer API key from MBTA. It’s free.

  • Open mbta.maxpat
  • Open the Max console window so you can see what’s happening with the data
  • click on the yellow [getstops] message to get the current bus stop data
  • Toggle the metro (at the top of the patch) to start polling
  • Turn on the audio (click speaker icon) and turn up the gain

Note: there will be more buses running during rush hours in Boston.  Try experimenting with the polling rate and ramp length in the poly-oscillator patch. Also, you can experiment with the pitch range.

Soundcloud API in Max8

This post describes an updated project.

The earlier version can be found here  https://reactivemusic.net/?p=5413

This project is part of the internet-sensors project: https://reactivemusic.net/?p=5859


2024/01/21: not working:

Soundcloud deleted my API credentials and is not accepting new requests. So there is really no point to using this project unless you have active credentials.

console.error() function crashes node. -fixed locally


In this patch, Max uses the Soundcloud API to search tracks and then select a result to download and play. It uses the node.js soundcloud-api-client https://github.com/iammordaty/soundcloud-api-client

For information on the soundcloud API http://developers.soundcloud.com/docs/api/reference



folder: soundcloud


main Max patch
  • sc.maxpat
node.js files
  • scnode.js


  • The Soundcloud client-id is embedded in scnode.js – you will need to edit this file to replace the worthless client-id with your own. To get a client ID you will first need a Soundcloud account. Then register an app at: http://soundcloud.com/you/apps

first time instructions

  • Open the Max patch: sc.maxpat
  • In the green panel, click on [script npm init]
  • In the green panel , click on [script install soundcloud-api-client]


  • Open the Max patch sc.maxpat
  • open the max.console window so you can see the API data
  • click [script start]
  • click the speaker icon to start audio
  • type something into the search box and press <enter> or click the button to the left to search for what is already in the box.
  • select a track from the result menu, wait for it to start playing

Spotify segment analysis player in Max

Echo Nest API audio analysis data is now provided by Spotify. This project is part of the internet-sensors project: https://reactivemusic.net/?p=5859

There is an older version here using the discontinued Echo Nest API: https://reactivemusic.net/?p=6296

Note:  Last tested 2024/01/21

The original analyzer document by Tristan Jehan can be found here (for the time being):  https://web.archive.org/web/20160528174915/http://developer.echonest.com/docs/v4/_static/AnalyzeDocumentation.pdf

This implementation uses node.js for Max instead of Ruby to access the API. You will need set up a developer account with Spotify and request API credentials. See below.

Other than that, the synthesis code in Max has not changed.  Some of the following background information and video is from the original version. ..

What if you used that data to reconstruct music by driving a sequencer in Max? The analysis is a series of time based quanta called segments. Each segment provides information about timing, timbre, and pitch – roughly corresponding to rhythm, harmony, and melody.




folder: spotify2


main Max patch
  • spotify-synth1.maxpat
abstractions and other files
  • polyvoice-sine.maxpat
  • polyvoice2.maxpat
node.js code
  • spot1.js
node folders and infrastructure
  • /node_modules
  • package-lock.json
  • package.json
  • You will need to install node.js
  • the node package manager will do the rest – see below.

Note: Your best bet is to just download the repository, leave everything in place, and run it from the existing folder


You will need to sign up for a developer account at Spotify and get an API key. https://developer.spotify.com/documentation/general/guides/authorization-guide/

Edit spot1.js replacing the cliendID and clientSecret with your spotify credentials

node for max install instructions (first time only)

  •  Open the Max patch: spotify-synth1.maxpat
  •  Scroll the patch over to the far right side until you see this green panel:

  • Click the [script npm init] message – this initializes the node infrastructure in the current folder
  • Then click each of the 2 script npm install messages –  this installs the necessary libraries


  •  Open the Max patch: spotify-synth1.maxpat
  •  Click the green [script start] message
  • Click the Speaker icon to start audio
  • Click the first dot in the preset object to set the mixer settings to something reasonable
  • open the Max Console window so you can see the Spotify API data
  • From the 2 menus at the top of the screen select an Artist and Title that match, for example: Albert Ayler and “Witches and Devils”
  • Click the [analyze] button – the console window should fill with interest data about your selection.
  • Click [play]
  • Note: if you hear a lot of clicks and pops, reduce the audio sample rate to 44.1 KHz.
Alternative search method:

Enter an Artist and Song title for analysis, in the text boxes. Then press the buttons for title and artist. Then press the /analyze button. If it works you will get prompts from the terminal window, the Max window, and you should see the time in seconds in upper right corner of the patch.


If there are problems with the analysis, its most likely due to one of the following:

  • artist or title spelled incorrectly
  • song is not available
  • song is too long
  • API is busy
Mixer controls

The Mixer channels from Left to right are:

  • bass
  • synth (left)
  • synth (right)
  • random octave synth
  • timbre synth
  • master volume
  • gain trim
  • HPF cutoff frequency
You can also adjust the reverb decay time and the playback rate. Normal playback rate is 1.

programming notes

Best results happen with slow abstract material, like the Miles (Wayne Shorter) piece above. The bass is not really happening. Lines all sound pretty much the same. I’m thinking it might be possible to derive a bass line from the pitch data by doing a chordal analysis of the analysis.

Here are screenshots of the Max sub-patches (the main screen is in the video above)

Timbre (percussion synth) – plays filtered noise:

Random octave synth:

Here’s a Coltrane piece, using roughly the same configuration but with sine oscillators for everything:

There are issues with clicks on the envelopes and the patch is kind of a mess but it plays!

Several modules respond to the API data:

  • tone synthesiszer (pitch data)
  • harmonic (random octave) synthesizer (pitch data)
  • filtered noise (timbre data)
  • bass synthesizer (key and mode data)
  • envelope generator (loudness data)

Since the key/mode data is global for the track, bass notes are probable guesses. This method doesn’t work for material with strong root motion or a variety of harmonic content. It’s essentially the same approach I use when asked to play bass at an open mic night.

additional notes

Now that this project is running again. I plan to write additional synthesizers that follow more of the spirit of the data. For example, distinguishing strong pitches from noise.

Also would like to make use of  the [section] data as well as the rhythmic analysis. There is an amazing amount of potential here.