DENON PMA-1500RII

Commentary

This pre-main amplifier is based on PMA-1500R and has been improved for next generation audio.

By reviewing the power amplifier circuit, etc., the upper limit of frequency characteristics in actual use has been improved to 100 kHz.
In addition, by using a low impedance volume, noise generated in the amplifier during actual use is reduced and resolution is improved.

A high-current amplifier UHC-MOS is used to achieve both high sound quality and speaker drive performance with the smallest amplifier. A single push-pull circuit using UHC-MOS achieves both expressive power and high power.

A twin transformer parallel connection has been adopted that greatly improves the characteristics of the magnetic circuit and winding.
In addition, by using the L. C. (Leakage Canceling) mounting method, which mutually cancels the influence of magnetism, etc., the leakage flux of the power transformer, which is a source of noise in the amplifier, is reduced, and improvement of power supply capability and low noise are realized.

The rectifier circuit uses the Schottky barrier diode used in the PMA 2000 III. The high-speed operation provides low-noise and high-current characteristics, enabling sound quality with less noise.

In addition to the independent configuration of the power amplifier block, the other circuits with different signal levels are also separated into separate block structures to prevent the deterioration of sound quality due to interference between circuits and noise inflow.
In addition, a radiator and stabilizer have been added to the power amplifier radiator, which is easily affected by vibration, to eliminate the influence of interference between blocks on sound quality.
The chassis is made of a steel plate that is carefully selected and a combination of a transformer base steel plate and a special resin to minimize vibration.

To reduce power consumption during standby when the remote power is turned off, a dedicated power transformer is installed in each of the microcomputer circuit and audio circuit. This not only reduces power consumption during standby but also eliminates interference from the microcomputer to the audio circuit.

Equipped with a microcomputer stop mode that automatically stops all operations of the microcomputer when it does not control, such as during listening. This stops the clock oscillation of the microcomputer during normal listening and eliminates noise from entering the audio system.

Transmission loss is reduced by gold-plating the brass machined parts of the speaker terminal. In addition, the hole diameter of the clamp section is φ 6 mm, making it compatible with large speaker cables.
In addition, the two speaker terminals can be bi-wired.

The phono equalizer uses a low-noise FET as a first stage discrete circuit.
In addition, it is compatible with each cartridge of MM/MC by switching the switch.

Built-in pre-out terminal.

Parts such as gold plated terminal, high sound quality carbon resistance and condenser are adopted.
The power cord is detachable.

It comes with a system remote control and also supports DENON CD, MD, cassette deck and tuner.
In addition, an independent power transformer is used for the power supply for the control circuit of the remote controller etc. to reduce interference to the audio circuit.

Model Rating

Type	Pre-main amplifier
Power Amplifier Unit
Rated Output (Both channel driven, CD → SP out)	70W + 70W (8 ohm, 20 hz to 20 khz, THD 0.07%) 140W + 140W (4 ω, 1 khz, 0.7% THD)
Total harmonic distortion factor	0.01% (Rated Output -3dB, 1 khz, 8 Ω)
Speaker output terminal	Speaker AORb : 4 Ω ~ 16 Ω Speaker A + B : 8 Ω ~ 16 Ω Bi-wiring load : 4 Ω ~ 16 Ω
Preamplifier Section
Input Sensitivity / Impedance	Phono MM : 2.5mV/47k Ω Phono MC : 0.2mV/100 Ω Line : 150mV/47k Ω (source direct off) 150mV/13k Ω (Source Direct On)
RIAA deviation	MM : 20 Hz to 20 kHz ± 0.5 dB MC : 30 Hz to 20 kHz ± 0.5 dB
Rated output	Equalizer amplifier output : 150 mv
<General>
Frequency characteristic	5 Hz ~ 100 kHz + 0 -3dB
SN ratio (Audibility compensation A, input short circuit)	Phono MM : 91 dB (at 5 mV input) Phono MC : 76 dB (at 0.5 mV input) Line:110dB
Tone control	Bass : ± 8 dB (100 Hz) Treble : ± 8 dB (10 kHz)
Power outlet	Switched : Route 3, 120W total
Power supply voltage	100 VAC, 50Hz/60Hz
Power consumption	250W Standby : Approx. 2W
External Dimensions (including legs, knobs, terminals)	Width 434x Height 134x Depth 407 mm
Weight	14.6kg
Attachment	System remote control