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Speak & Tweak

DLD Technology

  • • Retro speech synthesizer

Video clips

Audio examples

ST-1 Speak & Tweak is an emulation of the classic SP0256-AL2 speech chip that was a popular add-on for many home computers in the early 80s.

Speak & Tweak produces sounds using a crude model of the human vocal tract with 6 cascaded digital filters, white noise generator (breath) and tone generator. It contains 59 allophones which when concatenated correctly, can create most English words.

The result is a monotonic, robotic sounding voice that can be tuned precisely to any MIDI note, and is recognisable by anyone who's heard a speech chip from the early days of computing.

Version 1.1 also adds an audio input to allow you experiment with audio sources other than the built in pulse generator.

Product details

  • Emulation of SP0256-AL2 and English rules
  • Speed and pitch controls
  • Lock tempo control (allows multiple voices to play at same speed, different pitch)
  • Bucket Brigade Device (BBD) Delay
  • Polyphonic use
  • Single word per key modes
  • Damage control to artificially detune the filters
  • Slur CV input to repeat last allophone
  • Pitch bend and after-touch support
  • Low DSP usage
  • Plenty of CV inputs

Version 1.1 Adds:

  • Audio Input for vocoder style effects
  • Tempo synchronised delay

Version 1.2 Adds:

  • Pitch change on punctuation characters (',' '.' '!')
  • Sync 8th and Sync Quarter modes to synchronise word playback to music tempo

Manual available here



Released: 2015-12-16
Version: 1.2.0