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AV power amplifier equipped with 2ch/4ch switching function.

It is equipped with direct construction to minimize the signal path.
In direct construction, the input signal goes through a selector in a noise-proof shield case, and then directly from the front section to the main volume unit located at the shortest position controlled by a brass long shaft.
The level-adjusted signal is routed to the amplifier at the shortest distance and is output straight to the speaker jack.
With a circuit layout designed to minimize the signal flow, the circuit can be as short as 80 cm, minimizing the use of wires, which have been a cause of signal distortion and sound quality degradation.

Pioneer's proprietary super linear circuit is used in the power amplifier section to cancel the non-linearity of the transistor.
This circuit technology combines the non-linearity of a transistor with another transistor having completely opposite characteristics to cancel each other's non-linearity. This circuit technology brings out excellent low-distortion characteristics.
This makes it possible to minimize the amount of feedback in the entire amplifier stage, and reduces the number and capacity of capacitors, which adversely affect sound quality.

A clean ground system is used to prevent noise currents generated in the power supply and large current parts from entering the signal path and degrading the input signal.
The power transformer and heat sink, which were conventionally simply fixed to the chassis, are installed as a tight insulation structure to minimize the contact points where noise enters, and to separate the path of the input signal from the path where noise enters.
In addition, the bypass is set to return to the power supply, which is a source of noise, and the adverse effect of noise current is suppressed by these measures.

In order to prevent various internal and external vibrations from shaking the circuit board, leading to circuit instability and causing noise and distortion, we are committed to a vibration-free and resonance-free design.
In addition to hybrid chassis with bottom plate and shield case with greatly improved vibration damping characteristics by sandwich structure of different materials of PVC sheet and steel plate, strong and highly rigid structure is constructed by honeycomb heat sink and honeycomb frame with high vibration dispersion and absorption effect and improved strength at the same time.
In addition, five insulators are used to directly support the chassis frame.

With the same circuit design for each channel, super linear circuit, direct construction and strong power supply, the output power of 120W + 120W when driven by 2 ch and 70Wx4 when driven by 4 ch (both 6 Ω) is achieved.

It is equipped with 2ch/4ch switching function, and the input is 2 systems 3 inputs, and the speaker output is also 2 systems 3 outputs.
The input selector functions as a 2 ch, 2chx2, or 4 ch power amplifier.

Equipped with an auto output selector for use in combination with a digital surround field processor SP-91D.
For example, the SP-91D has surround field control and Dolby Prologic decoding, and the two modes of playback have different output speaker arrangements, such as processing front speaker and center speaker.
The Auto Output Selector automatically switches between the processing front speaker and the center speaker when you select the input mode for playback.

Model Rating
Type AV power amplifier
Rated Output (20 Hz ~ 20 kHz)
2 ch Drive : 150W + 150W (4 Ω, 0.02%)
120W + 120W (6 Ω, 0.01%)
100W + 100W (8 Ω, 0.009%)
4-ch drive : 75Wx4 (4 Ω, 0.04%)
70Wx4 (6 Ω, 0.03%)
55Wx4 (8 Ω, 0.02%)
Dynamic power (EIAJ test signal)
2 ch drive 2 Ω : 210W
4 Ω : 190W
Harmonic distortion factor (2 ch drive) 0.005% (20 Hz to 20 kHz, 50W, 8 Ω)
Input Sensitivity / Impedance Amp1, 2 : 1V/40k Ω
Frequency characteristic 5 Hz ~ 150 kHz + 0 -3dB
Signal-to-noise ratio (A network, short circuit) 2 ch drive : 120 dB
Power supply voltage 100 VAC, 50Hz/60Hz
Power consumption (Electrical Appliance and Material Control Law) 320W
External dimensions Width 420x Height 163x Depth 424 mm
Weight 20.2kg