Audio Database

SH-3380
Commentary

A demodulator for playback of CD-4 records, which are discrete 4-ch records.

4-ch and 2-ch automatic switching system is adopted.
It recognizes CD-4 records and stereo records by the presence or absence of a 30 kHz carrier signal, and automatically turns the muting circuit ON / OFF.
When a CD-4 record is played back, the demodulation circuit automatically activates and the 4-ch radar lights up to indicate that a CD-4 record is being played back. When a stereo record is played back, it functions as an ordinary equalizer circuit.

A unique noise reduction circuit is built in to reduce noise caused by wear and dust of records.
A PLL (Phase Locked Loop) circuit is adopted in the FM detection circuit that extracts the difference signal by FM detection of the carrier. This reduces the distortion and noise that occur when the carrier level drops due to degradation of records or when the carrier drops out due to dust.

In order to always take out the carrier signal in the best condition even if the output differs depending on the cartridge, a carrier level adjustment knob is mounted.
Thus, the output difference of the 4-ch cartridge can be corrected.

Equipped with two Phono input terminals.
As the separation and carrier level can be adjusted independently for Phono1 and 2, adjustment for each cartridge replacement becomes unnecessary once it is adjusted.

It uses a four channel master volume that can adjust the volume of four channels simultaneously.

Both semi-conductor and magnetic type cartridges can be used.

Model Rating
Type CD-4 System Disk Demodulator
Frequency characteristic 20 Hz to 16000 Hz
Rated input level
Phono1 SC:3.0mV
MM:1.5mV
Phono2 MM Low:1.5mV
MM High:7mV
Input impedance
Phono1 SC : 4.7k Ω
MM : 100k Ω
Phono2 MM Low : 100k Ω
MM High : 100k Ω
Rated output level 300mV
Output impedance 1.8k Ω
Semiconductor used IC : 4
Transistor : 41
FET : 6
Diode : 12 pcs
Power supply voltage 100 VAC, 50Hz/60Hz
Power consumption 5.7W
External dimensions Width 205x Height 141x Depth 335 mm
Weight 3.2kg