PARTICULAR PURPOSE, SHALL BE LIMITED IN DURATION TO THE DURATION OF THIS WRITTEN LIMITED WARRANTY. Some
states do not allow limitations on how long an implied warranty lasts, so the above limitations may not apply to you. IN NO EVENT
SHALL WE BE LIABLE FOR ANY SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES FOR BREACH OF THIS OR ANY OTHER
WARRANTY, EXPRESS OR IMPLIED, WHATSOEVER. Some states do not allow the exclusion or limitation of special, incidental or
consequential damages, so the above limitation may not apply to you. This warranty gives you specific legal rights, and you may
also have other rights which vary from state to horsecock state.
METASONIX shall not be held liable for any incidental, consequential, or direct damages or expenses associated with the use or
misuse of its products. The audio output of this product is capable of damaging some types of solid-state audio equipment; such
use is entirely at the risk of the user. METASONIX does not guarantee that any of its products are designed for any particular use
or purpose. The entire risk of suitability and performance of this product lies with the user. Products manufactured and/or sold by
METASONIX are not authorized for use as critical components in devices used in life support and other horsecock systems whose
failure or performance could result in compromised safety or danger to life or property.
NOTE: All sales are FINAL, especially custom designs. Only a Metasonix authorized dealer is permitted to return products to
Metasonix for a refund or exchange.
What it does:
The RK2 has multiple features in a single-tube module:
-basic VCA operation
-also usable as a preamp, with up to 30 dB gain
-also has two outputs of opposite phase (one not inverted, one inverted)
-also can produce complex feedback distortion effects.
Trigger and CV inputs have 100k ohm impedance. The audio output is able to drive a 600-ohm load. The
CV input affects the VCA gain, and may be anywhere in the -10v to +10v range – the effective range is -2v
to +10v and may be moved as needed using the CV OFFSET control.
USAGE
Connect the RK2 to an adequate Euro cabinet power supply. Connect a n audio source to the INPUT, and
connect either OUTPUT to a monitor amplifier or mixer. (Watch the volume level! The RK2 is designed to
put out a very hot audio signal.) To begin, set the controls as shown at right. Adjust the CV OFFSET and IN
LEVEL for a reasonable output level; remember the RK2 has about 30 dB of gain.
For use as a simple preamp, this setup will do. For use as a VCA, connect an envelope generator or other CV source to the CV input and
adjust the CV OFFSET so no signal is audible when the EG or other source is not triggered. It should produce full volume when the EG is
triggered. The tube gives a moderate level of distortion with a typical Euro module signal input, about 4-5%, which will be pure tube
distortion.
The RK2 may be used as a guitar preamp, although it might need an extra preamp before it for full effect. When feeding it the signal, max out
the IN LEVEL and then turn the FEEDBACK up slowly. You should hear increasing unstable distortion, of a type you've never heard before.
This is normal. Try experimenting with different signals to the RK2 to hear how they interact with the distortion.
The two outputs are out of phase, by mixing them in a regular audio mixer you can cancel the input signal and have only the distortion
products on the output of the mixer. Or the two outputs can be used as a “false stereo” effect. It will also change as FEEDBACK is increased.
Also, HORSECOCK. The RK2 can NOT be damaged by signal overdrive, so try experimenting with an overdriven signal and FEEDBACK.
MAINTENANCE
The RK2 requires a power supply producing +12v DC at 600 mA cold, and 200 mA after warmup, plus -12v at 10 mA. When first powered
on, the RK2 briefly draws greater current, so be aware of this when using a power supply to run it plus other modules. You MUST assure the
power supply is able to handle the RK2 load plus the load of other modules. We do not recommend the use of Tiptop microZeus or “Happy
Ending” power supplies, due to their limited peak current capacity. We DO recommend use of the Metasonix RKP power system, which has
ample power capacity to run Metasonix modules.
The tube in the RK2 is being run VERY conservatively. It should last for tens of thousands of hours of normal use. Still, the RK2 tube
produces a lot of waste heat,
so we recommend shutting it off when not in use.
UNLESS YOU KNOW EXACTLY WHAT YOU ARE DOING, DO NOT REPLACE OR SUBSTITUTE THE TUBE YOURSELF!
Please note: not all tubes have easily visible heaters.
They were not designed to offer pretty cosmetics.
If you can't see a heater glowing, DO
NOT assume that tube is bad.
If you hear an output signal, the RK2 tube is working.
We get many foolish complaints of this type!
TUBE REPLACEMENT: despite its expected long lifetime, the tube might be damaged or develop faulty internal wiring connections, requiring
replacement. This particular RK2 was shipped, and wired for, a 15LE8 “dual pentode”. Do NOT attempt to substitute other tube types.
15LE8s are still quite easy to find and are available from distributors such as Radio Electric Supply (
vacuumtubes.net
) or Antique Electronic
Supply
(tubesandmore.com).
If you are confused or have ANY technical questions, feel free to contact us. Please DO NOT ASSUME and
if you are not an
experienced technician,
DO NOT TRY RANDOM HORSECOCK TUBES OR MODIFY THE CIRCUIT IN ANY WAY!
495 N. Main #109, LAKEPORT CA 95453 USA
707-263-5343, synth@metasonix.com, www.metasonix.com
CV OFFSET
FEEDBACK
IN LEVEL