Audio Database

The

Accuphase C-260
370,000 yen(April, 1991 release)

Description

Control amplifier developed as a succeeding machine of C-200 series.

The balance transmission system is adopted as a line amplifier part.
Line-in amplifier is constituted from an input differential complimentary push pull + dregs cord push pull circuit, the input stage FET circuit has also become a dregs cord + constant current load, and high gm element is adopted as FET.
And if it inputs into both + (being un-reversed) and - (reversal), and a reversal input will be carried out to balanced input amplifier and it will input into being a ground and being un-reversed, it will become un-reversed type disequilibrium amplifier.
Furthermore, it has direct connection amplifier composition to which direct-current servo was applied.

Newly developed 4 linkage volume control machine is adopted as volume.
The resistance object of specular surface finishing especially with a small distortion is adopted, and by specular surface-ization, the distorted characteristic is good, and it excels in antiwear quality, and also what spoils sound qualities, such as grease, between a brush and a resistance object is not applied.
Moreover, unlike the structure of general volume, the resistance object rotated, the portion of the brush was fixed, and it came out to the directly exterior as a terminal, and by this, the metal joining section decreased to three places from five places, and the improvement in sound quality is achieved.
- (reversal) of an input balance circuit, and + (being un-reversed) -- this Attenuator goes into both, and since it is right-and-left channel linkage, it is considered as four structures which stood in a row.

The power-source part is considering each of equalizer amplifier, line amplifier, and presence control amplifier as the independent composition. Furthermore, the exclusive power transformer was formed in each right-and-left channel, and it has separated into it completely electrically.
Moreover, it is the unit amplifier with which each amplifier made the right-and-left channel become independent also mechanically, and right and left and interference between each unit are prevented.

The newly developed amplifier only for direct connection system headphone is carried.

The presence control which controls six kinds of frequency 4 point is carried.
It considers so that four most effective points can be adjusted on music expression, and the variable store of frequency has become six kinds 4 point.
The inside compass is 500Hz and 2kHz in center frequency, and 500Hz controls 2kHz of vocals etc. to expression of a rhythm musical instrument again. Moreover, Q which determines the sharpness of a crest has chosen Q= 0.707 from which a natural change is obtained based on the audition result of extensive program sauce.
Low-pitched sound and the loud sound can choose two kinds of frequency, respectively, and can adjust whole energy balance and atmosphere.
The composition of presence control consists of combination of few added type filters of sound quality degradation, and has prevented the characteristic and sound quality degradation by selecting carefully and using the element focused on sound quality. Furthermore, it is considered so that it may separate from a signal course in the state of the presence control off.

The equalizer amplifier part has composition equipped with the exclusive input circuit which matched the cartridge of MM and each MC.
At the time of MM input, it is made to consistent with the high-output impedance of a cartridge, constitutes from an FET element of high S/N, and is at the MC input time,Since a minute signal is received by low impedance, little reproduction of noise is enabled by constituting the difference input circuit by a low noise element, and attaining low impedance-ization of a NFB loop.
In accordance with the output of a cartridge, 60dB can be chosen in MC and the profit can choose 30dB and 36dB by MM.

The logic relay control circuit which uses the relay for communication industry which used nitrogen gas enclosure and a plated-with-gold contact for the audio change portion is adopted, and signal degradation by leading about of excessive wiring is prevented.

Balance imbalanced conversion amplifier for exclusive use is carried in the recording output for a balance input. Thereby, the balance input can treat tape relations like other imbalanced inputs.

Hearing impression at the time of small volume reproduction is rectified, and the loudness Compensation switch which prepares energy balance is carried.
It is +4dB in 100Hz : +6dB-20dB o'clock at the time of volume control position-30dB, and the degree of compensation is automatically adjusted by the volume control position.

The Attenuator switch with possible making it decrease to -20dB by one-touch is carried.

The Subsonic Filter is carried.

The upper surface bonnet gave the gold tone scratch hair line to thick aluminum hair line finishing, the front panel was given to aluminum, and both sides have attached the board of natural persimmon finishing.


Rear 4
Relay
Internal
Mother
A

Rating of a mode
Form Stereo preamplifier
Frequency response
balanced input (CD, Line) : 1.0Hz-600kHz+0 -3.0 dB
20Hz-20kHz+0 -0.2 dB
CD, Tuner, Line, Tape Play : 1.0Hz-600kHz+0 -3.0 dB
20Hz-20kHz+0 -0.2 dB
AD input: 20Hz-20kHz±0.2dB
THD 0.005% (with all the input terminals)
Input sensitivity/impedance
(at the time of an Output power / 0.5V output)
AD MM1:8.0mV/2.0mV/47kohm
AD MM2:4.0mV/1.0mV/47kohm
AD MC: 0.25mV/0.063 mV/100 ohms
Balanced: 252mV/63mV/40kohm
Unbalanced: 252mV/63mV/20kohm
An Output power/impedance Balanced output: 2.0V/50 ohm
Unbalanced output: 2.0V/1 ohm
Tape rec: 252mV/200 ohms
Headphone jack Conformity impedance: 4ohms - 600ohms
S/N and input conversion noise
Input terminal Input short-circuit IHF-A compensation EIA S/N
Rated input S/N Input conversion noise
AD MM1: 96dB -138dBV 85dB
AD MM2: 92dB -140dBV 86dB
AD MC: 80dB -152dBV 83dB
Balanced: 112dB -124dBV 94dB
Unbalanced: 116dB -128dBV 96dB
Maximum-except-take-off level
(0.005% of a distortion, 20Hz - 20kHz)
Balanced output:7.0V
Unbalanced output:7.0V
Tape rec:7.0V
The AD maximum inlet pressure
(1kHz, 0.005% of distortion)
MM1:250mV
MM2:125mV
MC:8mV
Minimum load impedance Balanced output: 600ohms
Unbalanced output: 1kohm
Tape rec: 10kohm
Gain Balanced input->Balanced output: 18dB
Balanced input->Unbalanced output: 18dB
Balanced input->rec output: 0dB
Unbalanced input->Balanced output: 18dB
Unbalanced input->Unbalanced output: 18dB
Unbalanced input->rec output: 0dB
AD MM (1/2) input->Balanced output: 48 / 54dB
AD MM (1/2) input->Unbalanced output: 48 / 54dB
AD MM (1/2) input->rec output: 30 / 36dB
AD MC input->Balanced output: 78dB
AD MC input->Unbalanced output: 78dB
AD MC input->rec output: 60dB
Presence control Four band systems
Frequency: 8kHz [ a 40Hz/100Hz change, 500Hz, 2kHz, and ]/20kHz change
Variable range: ±10dB
Loudness Compensation + 6dB (100Hz, Volume-30dB)
Subsonic Filter 17Hz, -12 dB/oct
Attenuator -20dB
The semiconductor used Transistor: 59 pieces
FET: 25 pieces
IC: 26 pieces
Diode: 57 pieces
Power supply voltage AC100V/117V/220V/240V, 50Hz/60Hz
Power consumption 19W
Dimensions the width 475x height 149(piece -- it includeds) x depth of 375mm
Weight 18.4kg