Audio Database

The

Accuphase C-222
220,000 yen(March, 1983 release)

Description

Control amplifier which aimed at the input terminal and the substantial function as an inheritor of C-220 which the acquisition of main elements of became impossible and carried out the end of production in 1980 though the chief aim was put on disc playback.

The circuit composition of equalizer amplifier and high-level amplifier is a predrive in the difference input and dregs cord through an FET buffer, and a final by Darlington, and the whole of each stage consists of push pulls.
the base before this gives NFB -- the characteristic has been improved and high quality is realized.

The composition which inserts exclusive flat amplifier in front of equalizer amplifier is adopted as the head amplifier for MC cartridges. Direct input of the circuit composition is carried out without the FET buffer, it selected the low noise element carefully, measured low impedance-ization of the NFB loop simultaneously, and has prevented generating of noise.
In MC head amplifier part, since the noise of the constant voltage circuit of a power source has big influence on S/N of a signal system, the low noise design which selected the element of the constant-voltage power-source part carefully, and was put into practice is performed.
Moreover, the maximum inlet pressure is 150mV so that it may not be saturated, also when mighty MC input passes.

direct-current servo circuit by IC was adopted as each of equalizer amplifier, high-level amplifier, and head amplifier, and a direct current generated in the output was detected, it returned to the input, and generating of direct-current drift is prevented.
Thereby, generating of direct-current drift becomes that there is almost nothing, and is making all the signal systems of the output direct connection from MC input.

Each unit amplifier is driven by the independent winding wire independent rectifier circuit, and the multiple power supply system which installs a constant-voltage power supply circuit in the near position of each unit amplifier further constitutes the perfect independent power source theoretically.

The signal from an input terminal was directly linked with the printed circuit board, the relay was entered and carried out to the near position, and the logic relay control which controls a relay by a logic circuit is adopted. This shortest-ized the signal course and degradation of the signal by leading about of excessive wiring is prevented.
In this case, the high reliability relay of the crossbar twin system developed as an object for audios is adopted especially as the relay used. A contact makes a golden thin film form on a silver palladium alloy, by using an encapsulated type, is intercepted from the open air and is raising durability.

In order to correspond to various MC cartridges and to be able to control sound quality minutely, MC input impedance is changed to a three-stage.
Moreover, the gain changeover switch is provided so that high gain of 32dB can be obtained to everything but a usual head amplifier profit of 26dB for a low output MC cartridge.

It is possible to carry MM load capacitance change function which tunes the high region characteristic of MM cartridge finely, and to add three kinds of capacity.

Two sets of tape contact buttons are carried, and recording, playback, and a monitor are possible.

It is possible to carry the Attenuator which can leave volume control as it is and can lower a level, and to lower a level to -20dB.

The Subsonic Filter of -12 dB/oct which cuts only a subsonic noise without affecting an audio frequency band is carried.

Instead of tone control, the Compensation which rectifies a frequency response automatically with the position of volume is carried. This function can choose two kinds of characteristics with a switch.

The headphone jack is carried.

There were C-222A to which the gold tone as a front panel main part in which those with two kind and a sub panel have the same design of the front panel was made, and C-222B made only to the sub panel with black.
Moreover, there was a cabinet of natural rosewood finishing as an option.


Rear The
Internal Head
Logic

Rating of a mode
Form Stereo preamplifier
Frequency response
Tuner, Line, Tape play : 1.0Hz-500kHz+0 -3.0 dB
20Hz-20kHz+0 -0.2 dB
Disc: 20Hz-20kHz±0.2dB
THD (IHF, 20Hz - 20kHz) 0.005% (with all the input terminals)
Input sensitivity/impedance
(An Output power / IHF output 0.5V)
Disc(Head amp off) MM: 2.0mV/0.5mV/47kohm
Disc (Head amp+26dB): 0.1mV/0.025 mV/10ohm, 30ohm, 100ohm
Disc (Head amp+32dB): 0.05mV/0.0125 mV/10ohm, 30ohm, 100ohm
Tuner, Line, and Tape play:126mV/31.5mV/20kohm
An Output power/impedance Outputs: 2.0V/1.0 ohm
Tape rec: 126mV/200 ohms (at the time of Disc)
S/N and input conversion noise
Input terminal Input short-circuit IHF-A compensation IHF S/N
Rated input S/N Input conversion noise
Disc(Head amp off)MM: 85dB -140dBV 85dB
Disc(Head amp +26dB): 72dB -152dBV 78dB
Disc(Head amp +32dB): 66dB -152dBV 78dB
Tuner, Line, Tape play : 110dB -128dBV 90dB
Maximum-except-take-off level (0.005% of a distortion, 20Hz - 20kHz) Outputs:8.0V
Tape rec: 19.0V (at the time of Disc)
Headphone jack Conformity impedance: 4ohms - 100ohms
The Disc maximum inlet pressure (1kHz, 0.005% of distortion) Head amp off:300mV
Head amp +26dB:15mV
Head amp +32dB:7.5mV
Minimum load impedance Outputs: 1kohm
Tape rec: 10kohm
Gain Tuner, Line, Tape play->Outputs:24dB
Tuner, Line, Tape play->Tape rec:0dB
Disc(Head amp off, MM) ->Outputs: 60dB
Disc(Head amp off, MM) ->Tape rec: 36dB
Head amp is +26dB and +32dB change type.
Loudness Compensation (Volume-30dB) 1:+3dB(100Hz)
2: +8dB (100Hz), +6dB (20kHz)
Subsonic Filter 17Hz, -12 dB/oct
Attenuator -20dB
The semiconductor used Transistor: 109 pieces
FET: Nine pieces
IC: 13 pieces
Diode: 94 pieces
Power supply voltage AC100V/117V/220V/240V, 50Hz/60Hz
Power consumption 50W
Dimensions the width 445x height 128(piece -- it includeds) x depth of 373mm
Width 466x height 153x depth of 385mm (at the time of wood cabinet wearing)
Weight 9.7kg
Option Wood cabinet A-9 (16,000yen)