Bastl Instruments launches “pocket-sized patchable synthbox” which generates melodies with ease

The Castle ARP is described as a “powerhouse of creativity,” yet its small enough to fit into the palm of your hand.

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Kastle ARP which is a tiny black square shaped synth

Image: Bastl Instruments

Bastl Instruments has launched the Kastle ARP, a compact modular melody generator based on a quantized sine wave oscillator with a digital waveshaper.

Described by the brand as a “powerhouse of creativity”, the Kastle ARP offers “unparalleled patch flexibility”, and comes shipped with 10 patch cables.

The synth is battery powered and small enough to hold in the palm of your hand. Its pitch selection utilises straightforward concepts to deliver delightfully glitchy and intricate melodies. Pitch can be selected using the Note and Chord inputs, and the synth’s quantized oscillator keeps things consistently in tune.

There’s a decay envelope which adds variation by occasionally skipping pitches before retriggering, and a timbre control so you can blend between noble sine waves and 8-bit chip-tunes.

Bastl says that Kastle ARP has a “versatile” LFO section, which has been inherited from the original Kastle Drum. In boot-mode, you can access the root note and fine pitch tuning. On top of that, the bass output plays the root pitch of the current chord, which is said to enhance the overall sound.

Users can also run the Kastle ARP through delay and reverb effects, and combine it with other Kastle synths. Check out the videos below to find out more and hear it in action:

Further specifications include:

  • NOTE knob to browse through eight octaves
  • Timbre xor waveshaper
  • CHORD CV input switches between three chords
  • CV controllable decay envelope generator
  • Triggered pitch with “negative” decay to achieve melodic variation
  • Voltage-controllable clock with square and triangle output
  • Stepped voltage generator with random, 8-step, and 16-step loop modes
  • Two I/O CV ports routable to any patch point
  • The main OUT capable of driving headphones
  • 3x AA battery operation or USB power, selectable by a switch
  • Open source
  • Black and silver PCB enclosure

Kastle ARP is available now directly via Bastl Instruments for €107 (tax excluded).

Find out more over at Bastl Instruments.


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