Audio Database


A pre-main amplifier that combines the small output versions of the control amplifier Model3300 and power amplifier Model240 into one.

The circuit configuration of the main section is the same as that of the Model240 except for the difference in outputs. It uses a differential-amplified, pure complimentary service, and all-stage direct connection OCL circuit.
In addition, the differential amplifier stage and the output stage of the push-pull configuration also use transistors of a selected perfect pair, and the basic circuit itself is adjusted so that the DC balance is perfectly maintained, and the power transistor is a 2-chip parallel push-pull configuration.
In addition, sufficient idling current is supplied to maintain class AB operation even at low level to reduce notching distortion peculiar to transistors and to take measures against higher-order and odd-order distortion.

The pre-section has the same circuit configuration as the Model 3300. The equalizer stage, tone control stage, and amplifier stage are also directly connected with differential circuits at the first stage.

The contact point of the switch is not easily plated with gold. Instead, a sufficient contact area is provided and the contact resistance is adjusted appropriately.

A cut core is used for the power transformer, and flux itself is suppressed by a transformer wound with a short ring.

Model Rating
Type Console stereo amplifier
Power Amplifier Unit
Continuous rated output
(both channels, 20 Hz to 20 kHz)
4 Ω : 125W + 125W
8 Ω : 100W + 100W
16 Ω : 50W + 50W
Total harmonic distortion factor 0.15% or Less (20 Hz to 20000 Hz, Rated Output)
Cross modulation distortion factor 0.15% or Less (20 Hz to 20000 Hz, SMPTE, at Rated Output)
Frequency characteristic 6 Hz ~ 80000 Hz + 0 -3dB
20 Hz to 20 kHz ± 0.25 dB
Power Band With 10 Hz to 40000 Hz
Dynamic range 100dB
Channel separation 60dB
Damping factor 100 (8 Ω)
Tone control Treble : ± 10 dB (10 kHz)
Bass : ± 10 dB (100 Hz)
Preamplifier Section
Input Sensitivity / Impedance Phono : 1.35mV/47k Ω
High Level : 135mV/100k Ω
Output Level / Impedance Tape Recorder : 3V/1k Ω
Headphones : 3V/8 Ω or more
Center Channel : 3V/1k Ω
Filter High Filters : 5 kHz, 9 kHz
Low Filters : 50 Hz, 100 Hz
Pwer 100 VAC, 50Hz/60Hz
Power consumption 420W
External dimensions Width 390x Height 146x Depth 356 mm
Weight 14.1kg