Tube Works 500 Operation Notes

MosValve 500

Operation Notes

This amplifier was designed primarily for musical instrument amplification. It is an addition to your audio rig
which will add warmth and definition to your sound.
Use MosValve with any preamp capable of producing 775 MV into a 20K load (Virtually any preamp in ex-
istence.)
Use with speakers or cabinets capable of at least 400 watts RMS continuous power. Remember that Mos-
Valve can typically produce in excess of 400 Watts/channel under typical conditions common on stage to-
day. At least 400 Watt speakers or cabinets are therefore highly recommended if you intend to use the
amp at high power output. MANUFACTURER IS NOT RESPONSEBLE FOR ANY SPEAKER FAILURE
WHILE USING THIS EQUIPMENT.
This is a stereo power amp. Mono operation is switchable (both channels input bridged) with the use of
Channel A inputs. Normal stereo operation is only possible with the rear-panel switch set to "stereo".
Note: Channel B inputs are disabled when MONO mode is used. Only Channel A inputs can be used in
this mode.
It is often advisable to use only one channel for mono (for example, if you have only one speaker cabinet),
as the MosValve can produce over 400 Watts with only one channel driven. Use Channel A and set Chan-
nel B controls to "O." NOTE: It will not damage Channel B to have no speaker plugged into it while using
only Channel A.
NEVER attempt to power bridge the two speaker output channels together. NEVER parallel or series them
into one speaker or cabinet. If power from both channels is used, ALWAYS use at least two separate
speakers (one per channel) or separate speaker cabinets per channel. ALL WARRANTIES WILL IMMEDI-
ATELY BECOME VOID IF ANY ATTEMPT AT POWER BRIDGING, OR PARALLEL / SERIESING OUT-
PUTS ARE MADE!!
A certain amount of heat during operation is normal. The MosValve amplifier is biased in a manner in
which even when idling there is some heat present. It is best to keep the amplifier towards the bottom of
the rack (coolest air) and avoid obstructions to the vents in the case. DO NOT DISABLE THE FAN.
Never load the speaker outputs with less than 4 ohm loads. These can be single speaker cabinets per
output or a combination of two cabinets per output. Examples of cabinet combinations:
Min. 4 ohm per channel: One 4 Ohm system ; Two 8 Ohm systems (in parallel);
Four 16 ohm systems (in parallel).