Audio Database

The

DENON PMA-690
66,000yen(1992 release)

Description
 
The Integrated Amplifier which attained high-quality sound-ization by loading of a toroidal transformer or adoption of the New super optical ClassA circuit.

The NEW super optical ClassA circuit which is the specific technology of DENON is carried in the power amplifier part.
By the newly developed bias control circuit, magnification operation was carried out as a pure Class-A to the general listening power level, and sound quality of a Class-A no one but is realized. Moreover, the optical element was used for transmission of the control signal sent to a bias circuit from a bias control circuit, and the main signal system and an interference mutual [ between bias controlling circuits ] are completely eliminated to it.

By adopting a toroidal transformer and a large-sized electrolytic condenser, momentary response power is raised to the power-source part.

The signal course on either side was made into the shortest, and also the chassis construction made to separate is adopted.

In PMA-690, the power amplifier part and the preamplifier part were symmetrically divided into right and left, respectively, and the magnetic flux of a power-source part lock has prevented jumping into other Brock thoroughly.

In order to eliminate an unnecessary functional circuit as much as possible in sound, shortest-ization of the signal course reached from an input terminal to a speaker terminal is attained. This performed switch and proper arrangement of volume and shortening of a large distance is realized.

In order to improve the S/N ratio in a listening level, low impedance volume control is adopted.

By Rec out Selector, the recording of the sauce which is not related to a speaker output is possible.

The Source Direct is carried and, in on, control circuits, such as Bass/Treble/Balance/Loudness/Sub sonic, are bypassed.

Phono Selector which does not choose the cartridge of MM/MC is carried.

Rear
Internal

Rating of a mode
Form Integrated Amplifier
<Power amplifier part>
Output power (20Hz - 20kHz) 130W+130W (6ohms)
105W+105W (8ohms)
A dynamic characteristic / dynamic power 350W (2ohms)
270W (4ohms)
THD 0.004% (1kHz, 52.5W, 8ohm)
Output bandwidth 5Hz - 50kHz (Outputs 52.5W and 8ohm, 0.03%)
Line-in frequency response 4Hz-150kHz+0 -3 dB (outputs 1W and 8ohm)
Speaker output terminal AorB: 6ohms - 16ohms
A+B: 12ohm-16ohm
Headphone maximum except take-off 33mW (8ohms)
<Preamplifier part>
Input sensitivity/impedance Phono MM: 2.5mV/47kohm
Phono MC: 0.2mV/100 ohms
Tape1, 2, CD, Tuner, Aux:150mV/47kohm (at the time of sauce direct-off)
Tape1, 2, CD, Tuner, Aux:150mV/10kohm (at the time of sauce direct-on)
The maximum except take-off/Output power 10V/150mV
THD 0.001% (1kHz, 1V)
RIAA deflection 20Hz-20kHz±0.3dB
<Synthesis>
Signal to noise ratio
(the auditory sensation weighting A, input short circuit)
Phono MM: 94dB (at the time of a 5mV input)
Phono MC: 75dB (at the time of a 0.5mV input)
Line input: 110dB (at the time of sauce direct-on)
Tone control characteristic Bass: ±8dB (100Hz)
Treble: ±8dB (10kHz)
Loudness control 100Hz:+7dB
10kHz:+6dB
Subsonic Filter 16Hz, -12 dB/oct
Power supply voltage AC100V, 50Hz/60Hz
Power consumption 180W
Dimensions (a base, a knob, a terminal included) Width 434x height 160x depth of 398mm
Weight 12.4kg