Pioneer A-006

Commentary

4 DC pre-main amplifier with built-in MC head amplifier.

It is a 4-DC amplifier configuration in which all amplification stages from the sound inlet to the sound outlet are converted into DC.
Since all of the MC, equalizer, flat and power amplifiers are DC amplifiers, NFB is stably applied over a wide band, suppressing low-frequency phase shift, damping degradation, and transient intermodulation distortion caused by capacitors.

Built-in DC configuration MC head amplifier is compatible with MC cartridge.
The circuit configuration is a 3-stage direct-coupled class A SEPP-DC amplifier using an ultra-low noise transistor at the first stage.

The DC-configuration equalizer amplifier has a 3-stage direct-coupled configuration with a cascade connection of low-noise dual FETs, and a high S / N ratio is obtained by the ICL circuit without the input capacitor.
In addition, even when the cartridge is mounted with an increase in input impedance, a sufficient S / N ratio is secured and a high allowable input is obtained, so that programs with a wide dynamic range can be reproduced.

The power supply consists of a large transformer and a 12,000 μ Fx4 capacitor, and the ultra-low frequency characteristics are improved by low-impedance wiring.
In addition, the ultra-high frequency range is extended by the adoption of the group transistor EBT with excellent high-frequency switching characteristics.

The power amplifier uses class AB operation, which achieves both the features of class A operation and class B operation.
The amplifier operates at A-class power with emphasis on sound quality when viewed at home, and has high power efficiency close to that of a B-class amplifier, providing a large dynamic range even during peak hours.

Equipped with a subsonic filter with slope characteristic switching.
It also has a muting switch and a tone ON-OFF switch that can bypass the tone circuit.

The volume uses a 32-step attenuator that displays in decibels.

Equipped with a duplicate switch that allows free copying of tapes from 1 to 2 and from 2 to 1.

The pre-part and power part can be used separately.

Model Rating

Type	Stereo pre-main amplifier
Power Amplifier Unit
Effective output (both channel drive, 8 Ω)	70W + 70W (5 Hz ~ 30 kHz, THD 0.01%) 70W + 70W (5 Hz ~ 70 kHz, THD 0.05%)
Harmonic distortion factor	0.01% (Effective Output, 5 Hz to 30 kHz, 8 Ω)
Intermodulation distortion factor (50 hz : 7 khz = 4 : 1)	0.01% (8 Ω at effective output)
Output Bandwidth (IHF, double-channel drive, 8 ω)	5 Hz ~ 50 kHz (THD 0.01%) 5 Hz ~ 100 kHz (THD 0.05%)
Frequency response (at 1W output)	5 Hz ~ 200 kHz + 0 -1dB
Damping factor	40 (5 Hz ~ 30 kHz, 8 Ω)
Signal-to-noise ratio	115 dB (IHF, A-network, short circuit)
Preamplifier Section
Input Sensitivity / Impedance	Phono1, 2 (MM) : 2.5mV/100 Ω, 10k Ω, 25k Ω, 50k Ω, 100k Ω Phono1, 2 (MC) : 250 μ V/100 Ω Tuner, Aux, Tape play1, 2 : 150mV/50k Ω
Cartridge load capacity	Phono1, 2 (MM) : 100 pF, 200 pF, 300 pF, 400 pF, 500 pF
Phono maximum allowable input (1 kHz, 0.01% THD)	MM:300mV MC:30mV
Harmonic distortion factor (5 Hz to 30 kHz)	0.005% (1 V Output) 0.01% (10 V Output)
Frequency characteristic	Phono : 20 Hz to 20 kHz ± 0.2 dB Tuner, Aux, and Tape play : 5 hz to 100 khz + 0 to 1 db
Signal-to-noise ratio (IHF, A-network Short circuit)	Phono MM:90dB Phono MC:73dB Tuner, Aux, Tape play : 105 dB
Subsonic filter	15 Hz, 6dB/oct., 12dB/oct.
<General>
AC outlet	Power switch interlock : 2 systems Power switch not linked : 2 systems
Power supply voltage	100 VAC, 50Hz/60Hz
Power consumption	190W (Electrical Appliance and Material Control Law) 500W maximum
External dimensions	Width 420x Height 155x Depth 378 mm
Weight	14.6kg