DENON PMA-1010D
¥ 178,000 (around 1987)
Commentary
Pure A-class pre-main amplifier with built-in D/A converter.
It is class A amplified up to 1W output (8 Ω) in consideration of the quality at low power.
In class A push-pull operation, distortion is small, and the waveform of the sy passing current flowing through one transistor near the 0 cross becomes continuous instead of pulse. Therefore, transient and secondary accidents do not occur not only in electrical vibrations but also in mechanical vibrations of transistors and heat sinks.
In order to cope with the temperature rise of class A amplification, the fin of the heat sink is doubled, and the block is firmly combined with a copper plate with good heat conduction and fast vibration damping, to achieve high heat resistance and no resonance.
The power stage is a parallel push-pull of a Pc130W power transistor and has a unique super non-feedback configuration.
The power supply section is equipped with a large power transformer, fast recovery diode for high-speed rectification, and 48,000 μ F electrolytic capacitor for audio.
Stabilization is achieved by the adoption of balanced floating power supply system.
A large heat sink separates the power supply from the main signal system.
Equipped with a phono equalizer for MC/MM.
The first stage is an equalizer DC amplifier in which differential amplification by low-noise FET is connected in parallel, and the power supply is also strengthened.
It also has a subsonic filter dedicated to Phono.
The D/A converter uses a 4 DA push-pull super linear converter.
This converter consists of two carefully selected D/A converters for the left and right channels, each of which functions like a class A push-pull. It also consists of a four times over-sampling digital filter, a sample-and-hold circuit, and an LC-OFC 7th-order C. A. L. P. (linear-phase) low-pass filter.
The digital input section consists of a coaxial digital input Route 3 and two optical digital input systems. Equipped with a digital input selector using a high-speed C-MOS logic circuit, it automatically identifies CDs, DAT and DBS and transmits them to the D/A converter.
In addition, in order to eliminate interference with the converter section, "opto-isolated" method by optical coupling is adopted.
The digital interface circuit and the D/A converter circuit are built on separate circuit boards and shielded between them.
The interface circuit is equipped with a dedicated power supply that is independent from the secondary side of the transformer to prevent interference from digital signals, which is a source of noise from analog signals.
The entire unit is covered with a shield case that also acts as vibration isolation for the chassis and circuit board to prevent digital signals from leaking to other analog inputs, controls and power amplifiers.
Equipped with a digital output.
It uses a source direct switch that connects all input sources directly to the power amplifier for complete DC conversion.
It has a processor loop function which can be connected to a graphic equalizer.
Broadband real-time tone control.
Power cord with polarity display.
Model Rating
Type | Pre-main amplifier with digital multi-interface |
Power Amplifier Unit | |
Rated Output (20 Hz ~ 20 kHz) | 140W + 140W (8 Ω) 170W + 170W (6 Ω) |
Input Sensitivity / Impedance | Processor loop input : 150mV/47k Ω |
Total harmonic distortion factor | 0.003% (20 Hz to 20 kHz, 70W, 8 Ω) |
Cross modulation distortion factor | 0.002% (equivalent to 140W, 8 Ω) |
Dynamic Power | 670W (2 Ω, TIM Distortion Rate Measurement Limit Value or Less, Slew Rate ± 350 V / μ s or More) |
Output bandwidth | 5 Hz ~ 100 kHz (70W output, 0.5%, 8 Ω) |
Line input frequency characteristic | 1 Hz ~ 150 kHz, + 0 -3dB (1W, 8 Ω) |
Output impedance | 0.1 Ω or less |
Output terminal | Speaker : AORb : 6 ~ 16 Ω, A + B : 12 ~ 16 Ω (Terminal B is a direct connection) Headphone Jack Maximum Output : 550 mW (8 Ω), 8 ~ 400 Ω Compatible |
<Interface / DAC part> | |
Digital input / output level / impedance | Coaxial : 0.5Vp-p/75 Ω Standard optical input : 2 systems |
Frequency response (0 dB) | 5 Hz to 20 kHz ± 0.2 dB |
Signal-to-noise ratio (vs. 0 db, 1 khz) | 108dB |
Dynamic Range (1 kHz) | 97dB |
Total harmonic distortion factor (0 dB, 1 kHz) | 0.0023% |
Channel separation | 100 dB (0 dB, 1 kHz) |
Preamplifier Section | |
Input Sensitivity / Impedance | Phono MM : 2.5mV/47k Ω Phono MC : 0.2mV/100 Ω CD, Tuner, AUX, Tape1, 2, 3 (DAT, PB) : 150mV/47k Ω |
Maximum Output / Rated Output | 10V/150mV (Rec Out, Processor Loop Out) |
Total harmonic distortion factor | 0.001% (1 kHz, 8 v, Rec Out, Processor Loop Out) |
RIAA deviation | 20 Hz ~ 100 kHz ± 0.2 dB (IN ~ Rec Out & Processor Loop Out) |
<General> | |
SN ratio (input ratio (input short-circuit, auditory sense compensation A) | Phono MM:90dB Phono MC : 75 dB at 0.25 mV input Line : 110 dB (at 150 mV input) |
Tone control characteristics | Bass : ± 8 dB (100 Hz) Treble : ± 8 dB (10 kHz) |
Subsonic Filter for Phono | 16 Hz, -12dB/oct. |
Loudness control characteristic | 100Hz:+4dB 10kHz:+4dB |
Muting switch | -20dB |
Power consumption | 323W |
Pwer | 100 VAC, 50Hz/60Hz |
External dimensions (including feet, knobs, terminals, etc.) |
Width 474x Height 174x Depth 396 mm Side Plate Thickness : 20mmx2 |
Weight | 22kg |