Butler Audio MONAD A100 Stereo Amplifier User Manual


 
Description:
BK Butler’s MONAD A100 is a 300B Class A vacuum tube-driven
monoblock power amplifier. Both RCA and true BALANCED
precious metal plated input jacks of the highest quality are
provided. The RCA input jack and the 5-way speaker output binding
posts are top of the line Cardas. The 300B vacuum tube is
proprietary Butler design and manufactured per our specifications.
Sprague polypropylene capacitors, Vishay-Dale mil-spec 1%
resistors are employed throughout the entire audio chain. Internal
circuitry interconnections are positive military-type screw
connectors utilizing #10 hardware.
Power Output:
The MONAD A100 is powered by a 700W toroid power
transformer, which easily provides the necessary reserve power
necessary for continuous operation. An exceptionally large heat
exchange area on the internal heatsink is coupled into the large bulk
and mass of the CNC custom chassis for remarkably cool
operation. The MONAD A100 has reserve power capable of
producing 200 Watts into 4 ohm loads. Therefore an appropriate
source of 120VAC nominal input line voltage with a minimum
current supply of 5A is required. 230-240 VAC models require
approx. 50% of the current rating of 120V models.
Protection:
Listed below are the various types of internal protection provided
for unexpected conditions:
1. AC input fuse for protection against any major system power
fault. Do not replace with a fuse of higher current rating.
2. Thermistor-protected against AC input line transient voltage
spikes and surges.
3. Soft-start vacuum tube filament warm-up: Provides safe, fully
regulated, gentle turn-on 5.0 VDC for the 300B tube heater
filament. This technique promotes longest tube life.
4. Turn-on and warm-up transient delay: This circuit will not allow
the speaker relay to close (connect power module output to
speaker posts) for a delay of approximately 5 - 8 sec. after
turn-on. This provides for safe vacuum tube warm-up and
output stabilization.
5. DC Offset Voltage at Speaker Output: Continuous monitoring
circuit immediately opens the speaker relay upon the
detection of any excessive DC voltage level.
6. Short circuit protection: This continuously active circuit
becomes effective to the speaker output below a load of
approx. 2 ohms. It will prevent a catastrophic over-current