Audio Database

D-102
Commentary

A digital audio processor that enables you to enjoy digital audio from a video cassette by simply connecting to a home video deck.

The D-102 is equipped with a non-feedback active filter that is also used in the D-1, the first EIAJ digital audio processor announced in 1979. In addition, the D-102 has improved this non-feedback active filter by selecting a capacitor and reducing its size to improve sound quality.

A newly developed simple deglitch circuit is used in the deglitch circuit that eliminates the glitch signal generated during D/A conversion in the playback mode. This circuit reduces the degradation of the mid - and high-frequency range caused by the CR integration circuit and high-speed operational amplifier that occurs in circuits composed of conventional analog switches, CR integration circuits, and high-speed operational amplifiers.

The parts used for analog circuits and power supply circuits are carefully selected.
Only tantalum-based resistors are used. Capacitors are based on electrolytic acoustic capacitors with the best energy balance, and copper foil styrene capacitors, acoustic film capacitors, etc. are used according to the operation and function of each circuit part.
In addition, pure copper and copper-plated products are used for the housing, screws, wiring materials, etc., and only those with the best balance of characteristics are used, such as the adoption of low-feedback capacitance operational amplifier.

By reducing the power consumption of the digital circuit itself, improved sound quality and built-in power supply circuit have been realized.
The D-102 uses a C-MOS type, which has the advantage of low power consumption compared with the conventional N-MOS type, when the digital circuit is integrated into an LSI. It also uses a C-MOS type for a 16k-SRAM for wow and flutter removal and an 8-bit 1-chip microcomputer. This realizes low power consumption of 0.5W or less, while the power consumption of the N-MOS type is 3-4W.

The power supply is equipped with a Current Controlled Voltage Regulator (CCVR) power supply circuit developed based on the basic concept of "a power supply circuit suitable for digital audio." This improves the SN ratio of the power supply output by approximately 30 dB and does not use any capacitor in the power supply line.

Equipped with an auto fade-in / fade-out function using a digital fader circuit.

Model Rating
Type Digital audio processor
Method Compliant with Electronic Industries Association of Japan (EIAJ) technical file STC-007
Number of transmission channels 2 Channel
Modulation system PCM using the NTSC standard television signal
Sampling frequency 44.056kHz
Quantization 14-bit linear quantization
Transmission recording density 2,643 Mbit / s
Frequency characteristic 10 Hz to 20 kHz ± 1.0 dB
Dynamic range 90 dB (emphasis on)
85 dB (emphasis off)
Distortion factor 0.01% or Less (1 kHz, 0 dB Input)
Emphasis 50 μ S, 15 μ S
Drop-out compensation Correction by correction code combining 2 parity (P, Q) and CRC and correction by interpolation of average value
16-H word interleaving
Wow and flutter Below the measurement limit
Compatible VTR VHS, beta, U-matic
Power consumption AC : 13W
9W at DC input
External dimensions Width 270x Height 95x Depth 270 mm
Weight 3.3kg