Audio Database

The

DIATONE DA-A15
120,000yen(around the 1976 time)

Description
 
It is the power amplifier of Feature series.

The power source according to right-and-left channel and two sets of monophonic amplifier are constituted on the same chassis.
Thereby, the time combination and electrostatic coupling in the mutual intervention and high region from a power source are lost, and the separation between channels is improved.

The 3 steps of symmetrical full complimentary Darlington OCL circuit and the 2 steps of differential amplification current mirrored live system are adopted.
A symmetrical drive is possible and also a low distortion is possible for few distorted current mirror circuits conjointly at a three-step Darlington circuit and high gain with large direct-current current gain.

With the combination of the transistor which was excellent in the current mirrored live and the high frequency characteristic, the improvement of the standup characteristic of a pulse and the distorted characteristic of a high region is aimed at.

Two pieces and the electrolytic condenser of 70V or 12000-micro Fx2 are carried for the power transformer of 250VA in the power-source part.

The heat sink of 0.35 degree C per channel/W is attached to the exterior.
Thereby, a cooling effect is high and it is possible to use the junction temperature of a power transistor, stopping it low enough.
High reliability is conjointly secured with the parallel push pull of the power transistor of Pc=150W.

The speaker change has adopted the direct speaker terminal which uses the relay for protection as it is.
Thereby, since there is no conventional speaker changeover switch, the fall of the dumping factor by the contact resistance of a speaker changeover switch does not occur.

The preamplifier of Feature series, docking, and remote control are attained.



Rating of a mode
Form Stereo power amplifier
Output
20Hz - 20kHz : 150W+150W (8ohms)
200W+200W (4ohms)
1kHz: 160W+160W (8ohms)
230W+230W (4ohms)
Music power : 510W (8ohms)
860W (4ohms)
EIAJ (distorted 5%) : 400W (8ohms)
600W (4ohms)
THD
At the time of an Output power : 0.1%
At the W (20Hz - 20kHz) time of one : 0.02%
Output power (-3dB, 1kHz) : 0.003%
Cross modulation distortion (1W, 50Hz:7kHz=4:1) 0.03%
Input sensitivity/impedance 1V(variable) /50kohm
Frequency response (0.5W, -0dB one dB) 10Hz - 100kHz
Output bandwidth (IHF 0.1% distortion) 10Hz - 50kHz
Dumping factor 100
Channel separation
1kHz: 90dB
20kHz: 80dB
Remains noise 0.30mV
Muting time 5 seconds
Conformity load impedance 4-16ohm
Power source AC100V 50Hz/60Hz
Power consumption
Electrical Appliance and Material Control Law : 320W
Output power (8ohms) : 520W
Dimensions Width 425x height 170x depth of 285mm
Weight 18kg