Signal

The signal path, to be read from top to bottom

tapebow (stereo) x 3
DI-Box (stereo) x 3
Mixer
Computer (6 in, 3 Out)
Mixer
Loudspeaker x 3 (one loudspeaker per player, placed direct behind each player
so that the signal is also audible by the player)

Tapebow

Video Demonstration

A tapebow is simply a tape player (a walkman in most cases) in which the playhead has been mounted on a mute to be played by the bow. The bow-hair has been replaced by magnetic tape, with both channels containing the same audio material. The output of a tapebow is stereo!

Noise Reduction / Volume Pedal

The tapebow's signal is very noisy. For this, an active form of noise-reduction is used. A recommended way is to use a plugin which can take a snapshot of the noise profile and use this as a filter. One such plugin is implemented in REAPER

• Install REAPER (any version) (http://www.reaper.fm/download.php)
• Install the plugins under folder "noisereduction/plugins" for your operating system
• Open the REAPER session noisereduction/(the file ending in .RPP)
• Connect three expression pedals

Keyboard

Requirements

• A keyboard with at least 61 keys
• An expression pedal
• A sustain pedal
• A computer running linux, with an audio-interface (2 out)
• A keyboard amplifier

Installation

For Ubuntu >= 18.04:

$ cd midikeyb
$ ./install-ubuntu.sh

This will install all dependencies (csound, puredata for the gui, liblo for OSC)

Usage

We assume that the system is configured to use jack

1. Connect the keyboard, with an expression and a sustain pedal connected

2. Start jack

3. Connect the audio to the amplifier

4. At the terminal (in the midikeyb folder)

   $ ./zaehmungenkeyb.py

• This will start the csound-engine and a puredata patch for the gui
• Puredata is only used for gui (no audio)

5. Configure midi
   • With the patch running, click on "CONFIG"
   • This should open the configuration file in a suitable text editor
   • Otherwise, open the file ~/.zaehmungen/userconfig.json
   • Modify the value for CC_gainchange to match the CC sent by the expression pedal
   • Modify the value for CC_sustain to match the CC sent by the sustain pedal
   • "volpedal_curve" is an exponential factor applied to the midi values to change the mapping between midi and dB gain.
6. Other customizations:
   • RANDOM: this changes the randomness of the grains distribution
   • COMPRESS: how much to compress audio. Adjust gain accordingly (MAX_DB, MIN_DB)