This mini synth from Bastl proves that modulars don't have to be big or expensive

If you've been putting off getting into the modular synth world because of concerns over cost and/or space, Bastl Instruments' new pocket-sized Kastle could be the synth that gets you involved.

Battery-powerable and designed for producing "unique modulations and lo-fi sounds," this mini marvel can be used on its own or interfaced with other gear. It features a "complex" oscillator and LFO with stepped waveform generator, and a mini patchbay.

Check out a video demo above and a spec list below. You can order an assembled Kastle for €79 (available in less than a month), and a DIY kit for €65 (available in November), both from the Noise Kitchen website.

Bastl Instruments Kastle specs

  • Mini patchbay with 16 different patch points
  • 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 16 step loop 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
  • Comes with patch cables
  • The pattern on the sides varies and every unit is an original
Ben Rogerson

I’m the Deputy Editor of MusicRadar, having worked on the site since its launch in 2007. I previously spent eight years working on our sister magazine, Computer Music. I’ve been playing the piano, gigging in bands and failing to finish tracks at home for more than 30 years, 24 of which I’ve also spent writing about music and the ever-changing technology used to make it.