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MIDIBox SpeakJet

MIDIBox SpeakJet Synthesiser is a project that uses the MagnevationSpeakjet controlled by midibox as a standalone synthesizer.

The SpeakJet IC was brought to market in February 2004, and is available from a variety of vendors for around $25 USD.

From the SpeakJet Web Site:
The SpeakJet is a completely self contained, single chip voice and complex sound synthesizer. It uses a mathematical sound algorithm to control an internal five channel sound synthesizer to generate on-the-fly, unlimited vocabulary speech synthesis and complex sounds.

The SpeakJet is preconfigured with 72 speech elements (allophones), 43 sound effects, and 12 DTMF touch tones. Through the selection of these sounds and in combination with the control of the pitch, rate, bend, and volume parameters, the user has the ability to produce unlimited phrases and sound effects, with thousands of variations, at any time.

The SpeakJet can be controlled simultaneously by logic changes on any one of its eight event input lines, and by a single I/O line from a CPU allowing for both CPU-controlled and standalone operations.

Other features include an internal 64 byte input buffer, internal programmable EEPROM, three programmable outputs, and direct user access to the internal five channel sound synthesizer.

To build this Midi-playable nifty synthesizer project, you will need:

  • 1 MBHP Core Module (PIC18F, host of kII speakJet application → see below, communicates via IIC with the SJ-IIC-Module)
  • 1 MBHP SpeakJet-ICC-Module (PIC16F, receives IIC commands from Core and communicates via Serial Transmission with the Speakjet → breadboard construction described below)
  • 1 LCD, optional (2×16 for kII v 0.1.x; 1×8 LCD for kII v 0.2.x)

Where to buy ?

The MBHP SpeakJet IIC Module

This project is in progress at the moment. Please visit the Forum (and especially the first SpeakJet thread or see the links below for more info.


SpeakJet-IIC-Module Breadboard v1.3

If you need older outdated circuit versions, see SpeakJet Dev Archive

SpeakJet Application Software

This project is in progress at the moment. Please visit the Forum (and especially the first SpeakJet thread or see the links below for more info.

You need the following Software:

SpeakJet Controller Extensions

Currently some optional add-ons are being developed that allow various control of the MBHP-SpeakJet Project. You can add just one of them or all ;)

There are two controller extensions available for the SpeakJet project:

  • k64 Keyboard Modul → from Rio. Note that an adapted version of the k2 application based on v0.1 is required. The k64 has some additional synth functions, the original k2 app does not provide atm. Future k2-updates may or may not be compatible with this mod.

Further Information...

  • SpeakJet Demo - advanced possibilities (mp3, lowQuality, 32kHz, 80kbps, 3.1MB), shows what is possible with the current state of the project; you can hear how I control the five oscillators and later on mix it with MSA allophones (all from my microKONTROL, so easily controllable by any other midibox 8)
  • Latest SpeakJet Application Demo (kII) (mp3, midQuality, 44.1kHz, 96kbps, mono, 2,28MB), shows different control examples from phoneme tables controlled by jaw/tongue movement, single OSCs and also my approach to program a subtractive synthesis out of the 5 OSCs… try to hear the different waveshapes and the adding of distortion…
midibox_speakjet.txt · Last modified: 2016/06/09 01:17 by psykhaze