NEC AVD-1000PRO

Commentary

This is a Dolby Prologic decoder that pursues high sound quality by adopting an analog decoder.

The VCA uses the TDA1074A, which is the same IC as the professional decoder, and the VCA offset trimmer (professional decoder circuit), which is also used for the professional decoder, to eliminate the degradation of separation caused by the dispersion of VCA.
In addition, the VCA control uses F (tolerance of 1%) and G (tolerance of 2%) rank parts for filters and time constant circuits to minimize error voltage caused by variations in circuit parts.

For signal switching, a sealed twin crossbar contact relay (the contact is silver plated with gold) is used to guarantee low contact resistance and long-term reliability.

In order to minimize degradation of sound quality, 9 motor volumes including the master volume are built in.
On the signal path, no semiconductor switching is performed, and the variable signal level is controlled by a motor volume. Eight of these are controlled by a microcomputer. Individual differences in rotational speed are absorbed by the pre-learning function of the microcomputer, and each speed is controlled at a constant value.

The power transformer, which is a large source of vibration, is placed in the center to ensure the minimum weight balance, and the body is firmly supported by the 2 mm thick bottom plate and heavyweight legs (380g 65 φ 4-point or 4-facepiece possible).
In addition, the power transformers for analog and digital circuits are separated, and the housing is structurally and electrically.

In order to match the phases of the Lch/Rch of the input signal with each other, an auto-azimuth circuit adjusts the phase shift in real time to achieve accurate sound movement and localization.
(Retraction Range or Lock Range ± 15 ° 1 khz)

Equipped with an auto / input balance circuit, it automatically compensates for variations in input signals in real time.

It is equipped with a user logic function that allows you to create your favorite sound field. You can use the parameter set and surround invert functions.
In the parameter set, you can enjoy your favorite sound field by combining the effect of the directional enhancement circuit (EFFECT Fr/Re) and the cutoff frequency of the low-pass filter for surround channels (SR Cutoff).

By using a decorrelated DSP (Digital Signal Processor), you can expand the surround area and achieve the same effect as using two rear speakers.

It is equipped with newly developed large display tubes including the controller.

Equipped with an external input terminal for 4-channel HDTV broadcasting (3-1 format).

Various test tone functions allow for optimum system settings.
In the system test tone, the sound image of the test tone moves continuously from the front L channel to the center channel to the front R channel to the center channel to the front L channel.
Pulse test tones output pulses from both the center and surround channels simultaneously. In this case, the listener can sense the direction of the sound image from the channel where the sound arrives first by the Haas effect, which is useful for setting the delay time.

With a parametric equalizer, you can adjust the sound quality of the center channel when the center speaker is different from the front speaker.

Uses OFC thick power cord and gold plated terminal.

Two types of remote control units (setting remote control / steering remote control) are included.
Normal operation can be performed only with the steering remote control.

Model Rating

Type	AV surround decoder
<Input / Output Unit>
Input Sensitivity / Impedance	Input, Ext. in : 150mV/30k Ω
Output Level / Impedance	Front, Surround, Center, Mono : 1V/600 Ω
<Decoder Unit>
Analog (Stereo, Input → Output, Front)
Frequency characteristic	5 hz to 100 khz -3dB
Total harmonic distortion factor	0.003%(1kHz)
SN ratio (JIS-A)	105dB
Digital (User's Logic, Input → Output, Surround)
Frequency characteristic	5 hz to 20 khz -3dB
Total harmonic distortion factor	0.03%(1kHz)
Signal-to-Noise Ratio (CCIR-ARM)	76 dB (0 dB = 1 V, headroom> 15 dB)
<Others>
Power supply voltage	100 VAC, 50Hz/60Hz
Power consumption	55W
External dimensions	Width 430x Height 140x Depth 407 mm
Weight	14.4kg