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BASTL Instruments
Kastle Handheld Modular Synthesizer

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Item: N13-6384

Availability: In stock

Kastle Handheld Modular Synthesizer
Kastle Handheld Modular Synthesizer Kastle Handheld Modular Synthesizer

BASTL Kastle Modular Synth

Kastle, from BASTL Instruments, is a battery powered, portable mini modular synthesizer. It is both a great starter synth for beginners, as well as a fun tool for those interested in DIY. The overall character has a lo-fi digital sound, but can play the full range from melodic and clean sounds to harsher noise. It is an open source DIY project, which allows the user to adjust the firmware if needed. It uses two Attiny 85 chips, which an be reprogrammed with an Arduino. There are many different firmwares available for the Attiny chips. 

The oscillator in Kastle has three parameters, Pitch, Waveshape, and Timbre, each with voltage control. There are three synthesis techniques utilized, Phase Distortion, Phase Modulation, and Track & Hold modulation. There is a VC LFO for modulation with square and triangle outputs. There is also a stepped waveform generator for pseudo-sequences. 

Kastle Features

  • Complex oscillator
  • 3 synthesis modes: phase distortion, phase modulation and track & hold modulation
  • Pitch control with offset and CV input with attenuator
  • Timbre control with offset and CV input with attenuator
  • Waveshape control with offset and CV input
  • Voltage controllable LFO with triangle and square outputs and reset input
  • Stepped voltage generator with random, 8 step and loop 16 step mode
  • 2 I/O CV ports are available and can be routed to any patch point
  • The main output can drive headphones
  • 3x AA battery operation with power switch
  • Open source
  • Possibility of exchanging different LFO and OSC chips
  • The pattern on the sides changes and every unit is an original

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  • Battery Powered (2x AA)
  • Pocket Sized, Handheld
  • Open source software
  • Includes 10 Patch cables

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