DIATONE DA-A15
¥ 120,000 (around 1976)
Commentary
Feature series power amplifier.
The power supply for each left and right channel and two monaural amplifiers are configured on the same chassis.
As a result, the separation between channels is improved by eliminating mutual interference from the power supply and time coupling and electrostatic coupling in the high frequency range.
Uses a symmetrical full complimentary service 3-stage Darlington OCL circuit and a differential-amplified 2-stage current mirror drive system.
A 3-stage Darlington circuit with a large DC current amplification factor, a high-gain symmetric drive, and a low-distortion current mirror circuit combine to enable a low distortion factor.
By combining a current mirror drive and a transistor with excellent high-frequency characteristics, pulse rise characteristics and high-frequency distortion characteristics are improved.
The power supply is equipped with two 250 VA power transformers and a 70 V, 12000 μ Fx2 electrolytic capacitor.
A heat sink of 0.35 ° C / W per channel is installed externally.
As a result, the cooling effect is high and the junction temperature of the power transistor can be kept sufficiently low for use.
High reliability is ensured by the parallel push-pull of the power transistor of Pc = 150W.
For speaker switching, a direct speaker terminal that uses the protection relay as it is is adopted.
Thus, since there is no conventional speaker changeover switch, the damping factor does not decrease due to the contact resistance of the speaker changeover switch.
Feature series preamp and docking and remote control are available.
Model Rating
| Type |
Stereo power amplifier |
| Output |
| 20 Hz to 20 kHz : |
150W + 150W (8 Ω)
200W + 200W (4 Ω) |
| 1kHz: |
160W + 160W (8 Ω)
230W + 230W (4 Ω) |
| Music Power : |
510W (8 Ω)
860W (4 Ω) |
| EIAJ (5% strain) : |
400W (8 Ω)
600W (4 Ω) |
|
| Harmonic distortion factor |
| At rated output : |
0.1% |
| At 1W (20 Hz to 20 kHz) : |
0.02% |
| Rated output (-3dB, 1 kHz) : |
0.003% |
|
| Intermodulation distortion factor (1W, 50 Hz : 7 khz = 4 : 1) |
0.03% |
| Input Sensitivity / Impedance |
1 V (Variable) / 50k Ω |
| Frequency Response (0.5W, 0 dB-1 dB) |
10 Hz to 100 kHz |
| Output Bandwidth (0.1% IHF Distortion) |
10 Hz to 50 kHz |
| Damping factor |
100 |
| Channel separation |
|
| Residual noise |
0.30mV |
| Muting time |
5 seconds |
| Adaptive load impedance |
4 ~ 16 Ω |
| Pwer |
AC100V 50Hz/60Hz |
| Power consumption |
| Electrical Appliance and Material Control Law : |
320W |
| Rated output (8 Ω) : |
520W |
|
| External dimensions |
Width 425x Height 170x Depth 285 mm |
| Weight |
18kg |
