Audio Database

SM-10
Commentary

A stereo power amplifier that can also be used as a high-output monaural power amplifier.

Just as Marantz developed the Stereo Power Amplifier #15 by combining two monaural power amplifiers, the heat sink and hood are completely independent on the left and right.

The circuit configuration is based on Marantz's original Low-TIM design to reduce dynamic distortion. In order to obtain sound quality equivalent to that of pure A class in AB class, the parallel push-pull amplifier stage with 3-stage Darlington connection employs a super high-ft transistor that has amplification characteristics with a margin up to ultra-high frequencies to reduce switching distortion.
Operation can be switched between pure class A and class AB. It can also be used as class AB monaural power amplifier by BTL connection.

In addition to a large transformer, the power supply section uses a highly reliable computer grade audio capacitor for one channel 22,000 μ Fx2.

Built-in protection circuit using high-speed relay with temperature sensor for higher reliability.

Uses gold-plated input terminal.

It is equipped with an independent power switch and gain control with sub-panels dedicated to left and right.

Model Rating
Type Stereo power amplifier
Rated Output (20 Hz ~ 20 kHz)
Both channel drive : 120W + 120W (Class AB, 8 Ω)
30W + 30W (Pure Class A, 8 Ω)
BTL Drive : 350W (Class AB, 8 Ω)
Total harmonic distortion rate (20 Hz to 20 kHz) 0.01% (at rated output)
Intermodulation distortion factor (60 hz : 7 khz = 4 : 1) 0.01% (at rated output)
Frequency characteristic 10 Hz ~ 30 kHz + 0 -0.3 dB
DC ~ 100 kHz + 0 -2dB
Damping factor 350 (1 kHz, 8 Ω)
Input Sensitivity / Impedance 1.5V/30k Ω
Signal-to-noise ratio (IHF-A) 110dB
Pwer 100 V, 50Hz/60Hz
Rated power consumption (Electrical Appliance and Material Control Law) 320W
External dimensions Width 416x Height 146x Depth 334 mm
Weight 20kg