Bastl Instruments Kastle Drum

The Kastle Drum is a special edition of Bastl’s classic mini modular synth focusing on algorithmic industrial glitchy drums.

Kastle was originally released in Fall 2016 and gained instant popularity as an affordable, pocket-sized modular synth. It received a lot of feedback and introduced a much improved version v1.5 a year later. Now Bastl Instruments have revisited the concept once again with an alternative way to operate the same hardware.

The design process gave birth to a seemingly limited, but in fact an innovative and quite playful take on a rhythm box that is using some novel concepts, like the dynamic acceleration envelope to build “a lot of dynamic rhythm” out of very little modulation.

Drum sound synthesis with a unique dynamic acceleration charged envelope makes this rhythm box surprisingly versatile and extremely fun to play. The built-in VC clock generator with a stepped pattern sequencer can either run on its own or it can be synchronized to analog clock, while retaining the triangle LFO for parameter modulation.

The Kastle Drum is a mini modular synthesizer with a headphone output, 2 in/out ports for interfacing other gear, and it runs on just 3 AA batteries. It is ideal for beginners in modular synthesis, but it will add some quite unique functionality to any modular synthesizer system. It delivers the fun of modular synthesis at a low price and fits into your pocket so you can play it anywhere!

Kastle is an open source project with all resources obtainable from GitHub.

Features

• 8 drum synthesis styles
• ”noises” output for less tonal content
• DRUM selects drum sounds
• acceleration charge dynamic envelope
• decay time
• PITCH control with offset and CV input with attenuator
• voltage-controllable clock with square and triangle output
• stepped voltage generator with random, 8 step and 16 step loop mode
• 2 I/O CV ports that can be routed to any patch point
• the main output can drive headphones
• 3x AA battery operation or USB power selectable by a switch
• open source
• durable black & gold PCB enclosure

What’s in the box

• Kastle synthesizer
• 10 patch cables
• sticker
• batteries not included