DIATONE DA-P10
¥ 60,000 (around 1976)
Commentary
Feature series preamp.
The power supply for each left and right channel and each unit amplifier are of a separate monaural configuration for the left and right channels, and the volume and switches are used with sufficient consideration for separation.
This improves the separation.
In addition to improving the separation by minimizing the number of auxiliary circuits that cause sound quality degradation, a constant voltage power supply is used for the power supply at the heart of the amplifier to eliminate interference between the circuits.
The tone circuit uses a current mirror circuit with high voltage amplification, symmetric drive and low distortion, and the filter circuit uses an inverted Darlington emitter-follower circuit to achieve low distortion.
A low-noise transistor developed by Diatone is used in the first stage differential amplifier stage of the equalizer amplifier to obtain an input equivalent noise of -126dB (V) (IHF, A-curve correction).
A variable resistor with a unique switch is used for the tone control, and the time constant circuit is completely disconnected in the flat position to obtain a flat frequency characteristic.
The tone control volume is provided separately for the left and right channels to improve the separation, and the sound quality can be adjusted separately for the left and right channels.
A muting circuit using a reed relay is adopted to prevent noise when the power switch is turned on and off.
The remote control allows direct speaker switching of the power amplifier.
It can be docked with Feature series power amplifiers.
Model Rating
Type | Preamplifier | ||||||||
Input Sensitivity / Input Impedance |
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Phono maximum allowable input | 270 mv (1 khz, 0.1% harmonic distortion rate) | ||||||||
Output Voltage / Output Impedance |
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Harmonic distortion factor (20 Hz to 20 kHz) | 0.02% or less at 1 V output At 9 v output : 0.05% or less |
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Frequency characteristic |
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Channel separation |
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Tone control | Bass : ± 10 dB (100 Hz) Treble : ± 10 dB (10 kHz) |
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Subsonic filter | Low : 18 Hz, 12dB/oct. | ||||||||
Input reduced noise (IHF, A-network, input short) |
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Number of semiconductors used | FET:3 Transistor : 34 Diode : 15 LED:1 |
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Pwer | AC100V 50Hz/60Hz | ||||||||
Power consumption (Electrical Appliance and Material Control Law) | 15W | ||||||||
External dimensions | Width 425x Height 169x Depth 204 mm | ||||||||
Weight | 5.8kg |