Audio Database


Pioneer M-AX10
450,000yen(2000 release)

Dual drive amplifier which gazed at it and developed the DVD-Audio age as a compilation of the direct energy MOS FET which Pioneer has cultivated.

The speaker drive scheme in the 3 mode can be chosen by power amplifier loading of a total of four channels.
At a separate mode, it operates as four-channel independent power amplifier, and the cross interferencee of a speaker inter-unit is eliminated by bi-wiring interconnection by a dual mode. Moreover, in bridge mode, it operates as two-channel high power amplifier by bridge connection.

The direct energy MOS FET of the Pioneer original development is carried.
The direct energy MOS FET has very few energy losses, and has the distinctive characteristics excellent in a power linearity and low load-intensity drive capacity. This power element was large-capacity-ized further, and the operating error between channels is put into practice and eliminated by adopting as all the channels only the sorting article which it kept choosing further from high qualities.
Furthermore, by adopting the very small ceramic sheet of thermal resistance as the insulating material of a large-sized heat sink and MOS FET, the temperature rise over an interconnection signal input and the momentary temperature rise over a pulse nature input are minimized, and the speed of the retroaction at the time of the amount input of Oto and the transparency of sound are improved.
Moreover, newly developed Z bias circuit that controls the temperature coefficient of MOS FET was carried in the temperature compensation of the idle current, the drift of an idle current has been improved sharply, and the tone quality stabilized from immediately after the power source on is realized.

The wide-range linear circuit which can obtain gain required of a current feedback type one-step amplifying circuit was brushed up further, and the perfect discrete stream composition not using DC servo or operational amplifier is realized. The clear low-pass play is enabled by keeping NFB constant from super-low-pass one.

The Digital Accurate Control attenuator in a digital analog converter which overly controls a sound volume with high precision using a precision resistance element is carried in the volume. By two input switchings and a DAC attenuator functionality, the direct input from a compact disk player etc. is possible.
A DAC attenuator does not have aggravation of the SN ratio by the interlocking error or attenuator location between right-and-left channels, or a separation. Moreover, the ill effect by oscillation can be reduced.
Moreover, for the reason in the case of using it, connecting with a preamplifier, an attenuator through functionality can be used.

The newly developed low-impedance electric-field capacitor and the very-thick wire were used abundantly on the power source and the grand line, the Ultra Low Inpedance power circuit which put low-impedance-ization into practice is adopted, and the supply capacity of a momentary large current is improved.

The right-and-left independent twin stereo stream composition is adopted from a power source to the input/output terminal of a rear panel.
Furthermore, a signal path is formed into the simple & shortest, by carrying out the isolated rate of each block with a shielding case, the thorough analysis of the potential difference in a chassis, the magnetic field in a set, a temperature, the oscillation, etc. is conducted, and the environment is homogenized.

The newly developed aluminum extrusion material of the wall thickness type which achieved the right-and-left independency is adopted as a heat sink.
Three brass stays which made brass Naked material this and it took are combined with a hybrid, and it has become a construction holding heavy loads, such as a power transformer, an electric-field capacitor, and a heat sink. This is improving the rigidity of the component.

In order to protect an input/output terminal from the sound pressure of a speaker, the 2mm thickness steel plate which gave the copper plating is adopted as a rear stabilizer. Furthermore, brass Naked material is adopted also as an insulator and the oscillation is controlled.

Conductivity was raised to the chassis, the rear panel, the shielding case, etc., and the high conduction chassis by the copper plating steel plate which stops a RF noise is adopted.
Moreover, he chooses even one one-point part carefully, and is examining the tone quality by set package.

The hypermarket ring toroidal transformer of 355VA is carried in a power-source part, and low load-intensity drive capacity is improved.
Moreover, in the mass toroidal transformer, the power-source higher-harmonic regulation made difficult is cleared.


Rating of a mode
Form Dual drive amplifier
Output power (all the channel drives) 230Wx2/220Wx2 (1kHz/20 Hz - 20kHz, 0.15%, 6 ohms, Bridge)
200Wx2/190Wx2 (1kHz/20 Hz - 20kHz, 0.09%, 8 ohms, Bridge)
115Wx4/110Wx4 (1kHz/20 Hz - 20kHz, 0.15%, 3 ohms, Dual/Separate)
100Wx4/90Wx4 (1kHz/20 Hz - 20kHz, 0.09%, 4 ohms, Dual/Separate)
65Wx4/60Wx4 (1kHz/20 Hz - 20kHz, 0.08%, 8 ohms, Dual/Separate)
THD 0.08% (20Hz - 20kHz, 100W, 8ohm, Bridge)
0.06% (20Hz - 20kHz, 30W, 8ohm, Dual/Separate)
Frequency characteristic 5Hz-150kHz+0 -3 dB
SN ratio 125dB (Attenuator through on )
Channel separation 115dB (20Hz - 20kHz, Dual/Separate)
104dB (20Hz - 20kHz, Bridge)
Dumping factor 400(1kHz)
300 (20Hz - 20kHz)
Input sensitivity/impedance Input1 and 2:1V/47kohm
Supply voltage AC100V, 50Hz/60Hz
Power consumption 320W
Dimensions Width 440x height 178x depth of 420mm
Weight 25.8kg