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Description: 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 pre-configured 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 serial line, allowing for both CPU-controlled and stand-along operations.


  • Programmable, 5-channel synthesizer
  • Natural phonetic speech synthesis
  • DTMF and other sound effects.
  • Programmable control of pitch, rate, bend and volume.
  • Programmable power – up or reset announcements.
  • Multiple modes of operation.
  • Simple interface to microcontrollers.
  • Simple “Stand Alone” operation.
  • Three programmable digital outputs.
  • Internal 64 Byte input buffer.
  • Internal programmable EEPROM.
  • Extremely low power consumption.
  • Low pin count.
  • Multiple case styles available.


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Customer Comments

  • I wonder how old this typo ish…

    The SpeakJet can be controlled simultaneously by logic changes on any one of its eight Event Input lines, and by a single I/O serial line, allowing for both CPU-controlled and stand-along operations.

    “stand-along” in the last line, instead of stand-alone :P

  • YES! Now I can be rocking with Hawking.

  • A fun project to play with. I have a video:
    I used the TTS256 chip along with the speakjet. The TTS256 has some pronunciation “bugs” but you can get by with creative spelling.

  • Thanks for SparkFun, I have invented SpeakJet Parsers as a Rapid Application Development Tool…

  • By the time you’ve added the text to speech chip it’s barely $10 cheaper than the Emic 2. It’s smaller, less robot like and has has lots of cool features. Check it out Emic 2

  • Do the pins RC0 + RC1 offer 4 events each or 4 together ?

  • Check out my little robot. It can talk and sing using the speakjet chip.

  • I made a cool R2-D2 project with the SpeakJet chip and the SparkFun Mono Audio Amp Breakout. Check it out It’s a pretty neat chip.

    • R2-D2 is cool… but for a real challenge try do C-3P0 (just English, not all 6 million forms of communication)

  • Ok, I don’t get it. This was possible (same quality, same sound library) with the SPO-256 chip that Radio Shack sold over 20 years ago for $29.95.
    You’d think there’s something better by now? Better sound/voice processor somewhere?


  • Is there a library for non-English use?

  • me want :D

  • I created a Eagle Library File of the Magnevation SpeakJet and uploaded the file to EagleCadUSA. I’ll post the link once it’s ready, if anyone would like to add this to their project.

  • This might be the greatest way ever to ruin a Big Mouth Billy Bass.

  • Exterminate!! EXTERMINATE!!!! The Doctor shall be EXTERMINATED!!

    I’m sorry, I couldn’t resist.

  • i need a help in programming a speakjet with pic16f877a in mikrobasic ,please


  • What does 5 channel synth mean? It can be talking and making sound effects at the same time?

  • I composed a blog on using the Speakjet with a PICAXE-18M2 and an I2C temp sensor TMP102 in PICAXE Basic code for another programming example. Less than 40 lines of code made a system that compares the last temperature reading to the current one, and speaks “hotter” or “colder” if it changes a degree or more.

  • For an essay on connecting one to an Arduino, go to…
    Information on the necessary audio amplifier and encouragement to use the Phrase-a-lator are included.

  • Okay, I finally put my SpeakJet on the breadboard. Just have to say THIS THING IS AMAZING!! I had no idea how cool it would be. The robot sound effects alone are worth the price (“Is that you R2?”) And it was pretty easy to create some new words not included in the standard library. Robot profanity! (Childish, but hilarious). Hey, that might be useful for the Antimov thing, eh? Robot utters a few choice words before self destructing. ;-)

  • I ordered one of these and instead SFE sent me a 3 to 8 line decoder. Probably just a mixup, but how can this be fixed? It says M74HC238B1 on the back of the chip.

  • Just wondering, why does the IC in the picture have scratches on the top? It looks as though it has been used, or scratched by a cat (my cat loves to just chew on diodes and capacitors…)

    • Mr President, it’s probably scratched because it started life as a general-purpose flash-based microcontroller (PIC, AVR, etc.). The SpeakJet people loaded it with their code, removed (scratched off) the chip’s original markings, and put their own logo on it. Pretty common occurrence, if you can’t afford the lot size it would take to get the base chips without markings on them.

  • “How about a nice game of CHESS?”

  • What does “multiple case styles” mean?
    This looks AWESOME!! Can’t wait to order it!

    • Multiple case styles probably means that you can get it in a DIP, SMD, or some other package.

      • I’m not sure but that’s the normal definition, but here it is talking about the speakjets capability to speak the same letter or phrase at different pitches or “Case Styles” etc.

  • i believe you guys forgot to post the link to Magnevations speakjet software (phrase-a-lator).

  • Agreed, COOL!
    How clear is the speech?

  • Um.

Customer Reviews

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1 of 1 found this helpful:

really like it

great way to easily add speech and cool sound effects to (arduino) projects. Just wish it was cheaper….