Audio Database

PMA-680R
Commentary

This pre-main amplifier pursues operability while pursuing pure sound quality by adopting a large toroidal transformer and a new structure SLDC.

A toroidal transformer is used for the power supply section.
Unlike conventional transformers, toroidal transformers consist of a toroidal ring core with a coil wound around it, and have excellent characteristics such as stable supply of current, leakage flux, and vibration prevention.

A new structure S. L. D. C. (Signal Level Divided Construction) is adopted in order to suppress the mutual interference of each circuit.
By dividing the signal handling into low-level blocks, high-level blocks, and microcomputer blocks that handle digital signals, electrical interference between each block is suppressed.

The low-impedance volume reduces the impedance of the volume control circuit, preventing the S/N ratio and frequency characteristics from deteriorating at general listening levels.

It is equipped with an equalizer amplifier that can be used with either MC or MM cartridge by switching operation.

It is equipped with a source direct switch and can bypass control circuits such as Bass, Treble, Balance and Loudness by turning it on.

The linked side of the AC outlet is linked to the remote power on/off.

It comes with a system remote control that supports DENON CD players, cassette decks and tuners.
In addition, the muting switch on the remote control body can be used to cancel the sound from the speaker.

Model Rating
Type Pre-main amplifier
Power Amplifier Unit
Rated output 85W + 85W (6 ohm, 1 khz)
65W + 65W (8 ohm, 20 hz to 20 khz)
Total harmonic distortion factor 0.008% (1 kHz, 32.5W, 8 Ω)
Dynamic Characteristics / Dynamic Power 180W + 180W (2 Ω)
140W + 140W (4 Ω)
Output bandwidth 5 Hz ~ 40 kHz (Output 32.5W, 0.07%, 8 Ω)
Line input frequency characteristic 4 Hz ~ 100 kHz + 0 -3dB (output 8 Ω, 1W)
Output terminal AORb : 6 Ω ~ 16 Ω
A + B : 12 Ω ~ 16 Ω
Maximum headphone output 30 mW (8 Ω)
Preamplifier Section
Input Sensitivity / Impedance Phono MM : 2.5mV/47k Ω
Phono MC : 0.2mV/100 Ω
CD, Tuner, Aux, DAT/Tape1, 2 : 150mV/47k Ω (source direct off)
CD, Tuner, Aux, DAT/Tape1, 2 : 150mV/10k Ω (source direct on)
Maximum Output / Rated Output 10V/150mV
Total harmonic distortion factor 0.001% (1 kHz, 1 V)
RIAA deviation 20 Hz to 20 kHz ± 0.3 dB
<General>
Signal-to-noise ratio
(Audibility Correction A, Input Short Circuit)
Phono MM : 94 dB (at 5 mV input)
Phono MC : 75 dB (at 0.5 mV input)
Line input : 107 dB (when source direct is on)
Tone control characteristics Bass : ± 8 dB (100 Hz)
Treble : ± 8 dB (10 kHz)
Subsonic filter 16 Hz, -12dB/oct.
Loudness control characteristic +7dB(100Hz)
+6dB(10kHz)
Power supply voltage 100 VAC, 50Hz/60Hz
Power consumption 250W
External dimensions Width 434x Height 140x Depth 353 mm (including leg, knob, terminal)
Weight 7.8kg
Included : Wireless Remote Control RC-152
BATTERY 2 UM-3 (AA)
External dimensions Width 60x Height 176x Depth 18 mm
Weight 120g (including battery)