Solid State
Stereo Amplifier Model 400 has gained an international reputation as the
world's mos reliable and most accurate high powered amplifier. It puts out 201
watts per channel which enables it to drive all the better bookshelf speakers
as well as the most exotic loudspeakers available. It also rates better than
any amplifier in its power range on a dollar per watt basis.
If you
contemplating the purchase of high powered amplifier, you should audition the
Phase Linear 400.
Circuit
description
The Phase
Linear amplifier consists of two direct coupled designed linear power
amplifiers combined to form a single, dual channel unit capable of extremely
high power output. The output
stages employ twelve high current, high voltage, triple-diffused silicon output
transistors arranged in a quasi-complimentary format and biased for class AB
operation. The output
stages are driven by two stages of Darlington connected current amplifiers,
which in turn are driven by a predriver voltage amplifying stage swinging the
full supply voltage.
The upper
output transistors are driven into saturation by a constant current source and
the lower transistors are driven by the predriver. Bias control
is accomplished by a bias regulator consisting of two voltage reference diodes,
a regulator transistor, and temperature compensating circuitry. The low
level stage consists of a differential pair which provides voltage gain and
level shifting to accommodate the predriver requirements.
The patanted protective circuits consist of four small analog to digital computers,each computer monitoring the operating conditions of four output transistors. Output current,voltage, energy, time raate of current and voltage change, and common mode conduction are monitored continuously during amplifier operation. If the value any one, or the sum value of more than one or all of these quantities exceeds a safe stress level for the transistors, the computer instructs a "disconed circuit" to instantly shut down the amplifier.
Specifications:
Power: 201 watts per channel (min. RMS at 8 Ω,
20-20,000 Hz, with no more than ,25%T.H.D.)
Hum and
Noise: at least 100 dB below rated
output
Damping
Factor: 1000 : 1 at 20 Hz
Rise
Time: less than 1,7 microseconds
Phase
Shift: lagging 12 degrees at 20 kHz
Sensitivity: 1,75 volts for rated power output
Slew
Rate: 11 volts/microsecond.
Meter
ballistics: V.U. calibration is such
that impulsive waveforms result in 0 V.U. at clipping
Stability: absolutely stable with all loudspeakers
including electrostatic units.
Protection: electronic energy limiters together with
supply fuses prevent excursions into unsafe operating regions
Dimensions
(W x H x D): 19" x 7" x
10"
Weight: 35 lbs
Finish: light brushed gold, baked enamel and black
anodize.