Thorough maintenance was carried out, such as replacing capacitors and deteriorated parts! A custom model whose circuit was changed from the original to a non-feedback amplifier. The output drops by 5W+5W compared to the MQ60, but surprisingly, this one has a better amount of noise, and the sound quality is clean. The appeal is that it is easy to grasp the sense of localization. The exterior has a feeling of use such as dullness. Serial 40401535 (Tomonori Asaine)
Maintenance information: 2024.10.27 Maintained (vacuum tube socket, block capacitor, electrolytic capacitor, oil capacitor, SP and RCA terminals, semi-fixed VR, fuse, spark killer, diode, micro SW replacement. Load test, input/output waveform confirmation impedance switching SW/gain VOL decomposition contact refinement, application of anti-oxidation/sulfidation grease, input/output waveform confirmation, load test (1kHz sine wave, at 8Ω load: 25W+25W), sound output test)
Accessories: none
Main specifications: 50CA10 push-pull output 25W+25W (4/8/16Ω) 50CA10 x 4/12BH7A x 2/6267 W410 x H160 x D205 mm weight 14 kg