The RK1 is intended to serve as a “cymbal” or "snare" sound for synthesis of electronic drums. The use of vacuum-tube technology and a specially-chosen noise diode running at a high breakdown voltage insures that the RK1 gives a powerful, ass-kicking, crispy-crunchy sound.
It will punch you in the face. It will utterly crush the wimpy "606 cymbal" sounds produced by other solid-state drum sound modules or "vintage" analog drum machines.
A special selected noise diode generates the white noise, and a vacuum-tube pentode to gate the noise on and off. A built-in envelope generator allows adjustment of the attack and decay time. Long attack times will require triggering with a long positive pulse, while “typical” cymbal sounds can be made with a short trigger pulse. A trigger of at least +5 volts is recommended for best performance. A built-in high-cut filter allows adjustment of the noise sound from full-range to a rolloff of about 100 Hz, giving a unique "thunk" tone.
Trigger and CV inputs have 100k ohm impedance. The maximum audio output is extremely hot (more than +10 dBu) and able to drive a 600-ohm load. The CV input affects the DECAY time, and may be anywhere in the -10v to +10v range – the effective range is +1.5v to +5v. The RK1 is 8HP wide, protrudes behind the front panel no more than 1.5" (38mm), and the 6CB6 tube protrudes above the panel no more than 1.5" (38mm).
As with all Metasonix products, the RK1 is entirely handcrafted in California, from the best components available. Metasonix uses only "New Old Stock" premium tubes of American and European manufacture, and runs them conservatively for maximum lifetime.