Pioneer M-05

Commentary

Multi-channel power amplifier capable of 2 ch drive and 4 ch drive.

Direct construction is used to minimize the signal path.
After the input signal passes through a selector in a noise-proof shield case, it is input to the main volume unit located at the shortest position. This volume is controlled by a long brass shaft from the front knob to minimize the signal path. Then, it is led to the amplifier at the shortest distance and is output straight to the speaker terminal.
The total signal distance is limited to approximately 80 cm, further reducing signal transmission loss and improving sound quality.

A unique high-stability super-linear circuit is adopted, and the non-linearity of the transistor is canceled by combining it with another transistor with completely opposite characteristics to realize low distortion.

A unique clean ground system has been adopted. To prevent noise from entering the signal current, the heat sink and the power transformer are electrically separated, and a bypass circuit for passing noise current is provided to clean the signal ground.

Model Rating

Type	Multi-channel power amplifier
Rated Output (20 Hz ~ 20 kHz)	When 2 ch is driven : When driving 4 ch : 150W + 150W (4 Ω, 0.02%) 120W + 120W (6 Ω, 0.01%) 100W + 100W (8 Ω, 0.009%) 75Wx4 (4 Ω, 0.04%) 70Wx4 (6 Ω, 0.03%) 55Wx4 (8 Ω, 0.02%)
Signal-to-noise ratio	120 dB (IHF-A network, short circuit)
Input Sensitivity / Impedance	AMP1/2 : 1V/40k Ω
Frequency characteristic	5 Hz ~ 150 kHz + 0 -3dB
Total harmonic distortion factor	0.005% (20 Hz to 20 kHz, 50W, 8 Ω, 2 ch Drive)
Power supply voltage	100 VAC, 50Hz/60Hz
Power consumption	320W (Electrical Appliance and Material Control Law)
External dimensions	Width 440x Height 163x Depth 422 mm
Weight	20.2kg