If an external tank is used, the internal tank may be
disconnected by
carefully
pulling out the two small white
plastic connectors plugged into the blue-plastic tank
assembly, accessible from the rear of the R-56. Or, the two
tanks may be operated together in parallel, offering a far
greater range of complex reverb effects, especially by
operating the “Invert” switch. This gives a transient
cancellation effect similar to that found in the PAIA “Hot
Springs” reverb of the 1980s.
MAINTENANCE
The R-56 requires a power supply pro-12v DC at 800-
850 mA cold, and 300 mA after warmup. When first powered
on, the R-56 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 R-56 load plus the load of other
modules. We do not recommend the use of a Tiptop microZeus or “Happy Ending” power supply, due to
their limited peak current capacity.
The tubes in the R-56 are being run VERY conservatively. They should last for tens of thousands of
hours of normal use. Still, the R-56 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 TUBES 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. We get many foolish complaints of this type!
TUBE REPLACEMENT: despite their expected long lifetime, the tubes might be damaged or develop
faulty internal wiring connections, requiring replacement. This particular R-56 was shipped, and wired
for, two 12CT8 triode/pentodes. The R-56 can also accept type 7060 or 7258 tubes without modification,
types which are much more difficult to find than 12CT8s. Do NOT attempt to substitute other tube types.
12CT8s are still quite easy to find and are available from distributors such as Radio Electric Supply
(vacuumtubes.net) or Antique Electronic Supply (tubesandmore.com).
Note: this is an ADVANCED MODIFICATION and is NOT RECOMMENDED for inexperienced personnel.
The R-56 can be rewired to accept 5AN8, 6AN8 or 8489 triode/pentodes, by cutting the traces going to
the heater pins (4 and 5) and wiring those pins to a source of +5v power. This source will need to provide
about 3 amps of cold current and up to 1.2 amps of operating current after warmup. This is NOT a trivial
modification, and the assistance of Metasonix or a technician with experience in working with tube
electronics is mandatory.
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 TUBES OR MODIFY
THE CIRCUIT IN ANY WAY!
495 N. Main #109, LAKEPORT CA 95453 USA
707-263-5343, [email protected], www.metasonix.com
