Audio Database

The

Accuphase E-307
280,000 yen(December, 2000 release)

Description

The Integrated Amplifier which refined E-306V, concentrated the design technique cultivated until now, and aimed at higher completeness.

The power transistor for multi-emitter type large electric power audios excellent in many characteristics, such as the high frequency characteristic, a current gain linearity, and switching, is adopted as an output element.
This element is constituted from a parallel push pull, low impedance-ization is attained, it fixes on a large-sized heat sink, and efficient heat dissipation processing is carried out.

The current feedback magnification circuit the preamplifier part and the power amplifier part excelled [ circuit ] in the phase characteristic of the high region is adopted.
This circuit lowers the impedance of the input terminal which is a return side, detects current, carries out I-V conversion (current-voltage) of that current with a transformer impedance amplifier, and is making the output signal. Since the impedance of a return input portion is low, it is hard to generate phase rotation, and there is almost no necessity for phase compensation.
For this reason, many characteristics have been sharply improved by a little NFB, and the more natural energy response has been obtained.

The pure complimentary push pull circuit constituted from a discrete part is adopted as a line amplifier part, and this is made it with the current feedback magnification circuit.
Phase compensation of each stage also becomes light by this, and acquisition of natural sound quality is aimed at.

In order to make a straight signal course possible at the shortest, the logic relay control system is adopted.
The sealed type relay for communication industry is adopted as the relay used by this system, and low contact resistance and quantity durability are acquired by making a contact into a plated with gold and a crossbar twin system.

Tone control of an added type active filter system is carried in tone control.
This system passes an original flat signal straight, if needed, is another, and makes the characteristic, and sound quality is adjusted by making it adjust from a flat signal.

Two speaker terminals are carried and proper use and bi-wiring connection are possible by the change of a speaker selector.

The large-sized power transformer of about 500 VA is adopted as a power-source part. Moreover, two 22,000-micro F things are carried in the aluminum electrolytic capacitor for filters.
Furthermore, the exclusive power supply circuit is used for the preamplifier part handling a small signal, and interference with the power amplifier through a power-source part is prevented.

A preamplifier part and a power amplifier part are separated like internal structure and arrangement, and the mutual intervention is suppressed.

In order to monitor output electric power, the logarithm compression type analog type peak power meter is carried.

The separation switch and input-and-output terminal which can use a preamplifier part and a power amplifier part independently are carried.

The balance input is also carried in the input terminal.

The remote commander who can change volume control and an input selector is attached.

Playback of a digital input or an analog record is possible by extension of an option board.


Rear Option
An
Power Power Power Line
An Speaker Balance

Rating of a mode
Form Integrated stereo amplifier
Rated continuation average output
(Both channel operation, 20Hz - 20kHz)
140 W/ch (4ohms)
120 W/ch (6ohms)
100 W/ch (8ohms)
THD (both channel operation) 0.01% (4ohms - 16-ohm load)
IM distortion 0.01%
Frequency response High Level input, Main input :
20Hz-20kHz+0 -0.2 dB (at the time of a rated continuation average output)
2Hz-150kHz+0 -3.0dB (at the time of 1W output)
Dumping factor 100 (8-ohm load, 50Hz)
Input sensitivity/impedance
(An Output power / EIA1W output)
High Level input: 113mV/11.2mV/20kohm
Balanced input: 113mV/11.2mV/40kohm
Main input: 1.13V/112mV/20kohm
An Output voltage/impedance Pre output: 1.13V/50 ohm (at the time of a rated continuation output)
Gain High Level input -> Pre output: 20dB
Main input -> output: 28dB
S/N, input conversion noise
Input short-circuit and A-compensation EIA S/N
At the time of an Output power S/N Input conversion noise
High Level input: 104dB -123dBV 80dB
Balanced input: 88dB -107dBV 80dB
Main input: 122dB -121dBV 100dB
Tone control Low-pitched sound (300Hz): ±10dB (50Hz)
Loud sound (3kHz): ±10dB (20kHz)
Loudness Compensation + 6dB (100Hz, Volume-30dB)
Attenuator -20dB
Power meter Logarithm compression type peak level display
dB scale and the output Direct reading at the time of 8-ohm load
Load impedance 4ohm-16ohm
Headphone jack Conformity impedance: 4ohms - 100ohms
Power source AC100V, 50Hz/60Hz
Power consumption 50W (at the time of no inputting)
240W (Electrical Appliance and Material Control Law)
385W (at the time of an 8-ohm load Output power)
The maximum Dimensions Width 475x height 170x depth of 424mm
Weight 21.4kg
Attachment: Remote commander RC-20
Remote control system Infrared pulse system
Power source DC 3V
Battery AA -- type and two pieces
The maximum Dimensions Width 55x height 194x depth of 18mm
Weight 100g (Battery includeds)
Option: Option board
* DAC-10 can be used only to one sheet due to power capacity. Two-sheet use is possible for AD-10,
and the combination of DAC-10 and AD-10 is possible.
With no picture Line-in board Line-9 (6,000yen)
The common high-level input terminal of an imbalanced system.
Analog signals, such as CD player and a tuner, are played.

With no picture Analog disc input board AD-9 (30,000yen)
All cartridges are supported by loading of a high gain equalizer.
With an internal DIP switch, a MM/MC change, MC input impedance, and Subsonic-Filter on/off can be set up.

MM Gain: 36dB
Input impedance: 47kohm
MC Gain: 62dB
Input impedance: 10, a 30 or 100-ohm change
The Line-in board Line-10 (8,000yen)
The common high-level input terminal of an imbalanced system.
Analog signals, such as CD player and a tuner, are played.
The Analog disc input board AD-10 (50,000yen)
All cartridges are supported by loading of a highly efficient high gain equalizer.
With an internal DIP switch, a MM/MC change, MC input impedance, and Subsonic-Filter on/off can be set up.

MM Gain: 29dB
Input impedance: 47kohm
MC Gain: 60dB
Input impedance: 10, a 30 or 100-ohm change
With no picture Digital input board DAC-10 (50,000yen)
A MDS (multiple 冱igma) system D/A converter is carried, and the input terminal of the same axle/light is carried.
The digital music signal (32kHz - 96kHz of sampling frequencies/24 bits) is supported.

DAC-10 cannot be used for E-407, E-406V, E-306V, E-211, and C-265.