DIATONE DA-A10DC
¥ 90,000 (around 1978)
Commentary
This is a DC stereo power amplifier.
We emphasize phase distortion in the low frequency range and eliminate distortion by realizing DC without any capacitor that acts as the time constant of the amplifier circuit.
In the high-frequency range, distortion is reduced by improving the frequency bandwidth before NF is applied, enabling low-distortion reproduction over a wide range.
We have developed and adopted a dual FET with excellent characteristics, large gm (mutual conductance), and extremely low noise. We are working to improve the S/N ratio.
In addition, by using this dual FET, the drift of output terminal potential due to DC conversion is extremely small and stable operation is obtained.
A 2-monaural construction is adopted in which the power supply for each left and right channel and two monaural amplifiers are arranged on the same chassis. This eliminates the mutual interference of the power supply and greatly improves the separation.
A heat sink of 0.35 ° C / W per channel is installed on the outside. As a very large cooling effect can be obtained, the junction temperature of the power transistor can be kept sufficiently low for use.
Since the relay for protection is used as it is for speaker switching, there is no speaker switching switch, and the decrease in the damping factor due to the contact resistance of the switch is suppressed.
Model Rating
| Type | DC power amplifier |
| Output (20 Hz ~ 20 kHz) | 100W/100W (8 Ω) |
| Harmonic distortion factor (8 Ω, 20 Hz to 20 kHz) | 0.007% (1W output) |
| Intermodulation distortion factor (70 Hz : 7 kHz = 4 : 1, 8 Ω) | 0.007% |
| Output Bandwidth (IHF 0.1%, 8 ω) | 10 Hz to 100 kHz |
| Input Sensitivity / Impedance | 1 V (Variable) / 50k Ω |
| Frequency Response (0.5W Output) | DC ~ 150 khz + 0 -1dB |
| Residual Noise (Input Short) | 0.12mV |
| S/N (A network, input terminal short) | 120dB |
| Damping factor | 100 (8 Ω, 20 Hz to 20 kHz) |
| Channel separation (Input Terminal Short) |
1kHz:100dB 20kHz:80dB |
| Adaptive load impedance | 4 ~ 16 Ω |
| Pwer | 100 VAC, 50Hz/60Hz |
| Power consumption | Power Output : 240W Rated output : 390W |
| External dimensions | Width 425x Height 170x Depth 285 mm |
| Weight | 16kg |