LUXMAN MQ60

Commentary

This tube type stereo power amplifier is completed as an independent amplifier based on the main part of SQ38F.
NEC 50CA10 is used for the output tube as well as SQ38F.

The circuit configuration is based on the Mulard type. In order to take advantage of the characteristics of the circuit, a low internal resistance ball is used in the voltage amplification stage of the first stage to improve the high-frequency characteristics. In this section, 6267 is connected to a triode. In relation to this, a gain is obtained by using High Gm 6DT8 in the phase inversion stage, and NEC's triode 50CA10 is used in the output stage as well as SQ38F.

A phase correction circuit is inserted on the secondary side of the output transformer to prevent the amplifier from becoming unstable due to the attenuation of the load (near no load) in the high frequency range where the impedance of the speaker increases.
In addition, in order to avoid the influence of impedance from the input of the control amplifier, etc., buffer resistors are inserted into the first stage grid, and the fluctuation of frequency characteristics caused by volume change is suppressed.

OY15 type is used for the output transformer.

The chassis has an aluminum hairline silver finish with an all-dark gray semi-gloss paint.

There was also a model called KMQ60 which is an unwired and unadjusted kit for this MQ60.

Model Rating

Type	Bulb type stereo power amplifier
Continuous output	30W/30W (4, 8, 16 Ω)
Total harmonic distortion factor	0.1% (at 1W output) 0.3% (at maximum output)
Frequency characteristic	15 Hz to 60,000 Hz -1dB
Signal-to-noise ratio	90 dB or more
Residual noise	0.7 mV or less
Damping factor	Approximately 15 (1 kHz)
Load impedance	4 Ω, 8 Ω, 16 Ω (switch switching)
Semiconductors used	Vacuum Tubes (8 pcs) 50CA10 : 4 6DT8/6AQ8 : 2 6267 : 2 pieces Semiconductors (5 pcs) : DS16A : 4 DS16C : 1
External dimensions	Width 410x Height 160x Depth 205 mm
Weight	13.8kg
Sold Separately	MQ60 Kit KMQ60 (¥ 45,000) Bonnet (¥ 4,500)