¥198,000 (released in November 1981)
The Integrated Amplifier born from the development technology of the high-class amplifier that Accuphase has cultivated for many years.
MOS FET is adopted as an output element in the power amplifier section. Since the MOS FET is a voltage control type and is a wide band element, it has the characteristics that it prevents the occurrence of notching distortion that affects the sound quality in the high frequency range, and that it does not require power supply from the previous stage. Therefore, the load on the front stage becomes lighter, it is easy to select an element with excellent characteristics for the drive stage, and we have succeeded in improving the characteristics of the entire power amplifier section.
Moreover, since the last stage is a wide band, a wide band in the NF loop is possible, and the generation of harmful TIM as dynamic distortion is prevented.
Furthermore, the input stage is a FET buffer input, and the next is a push-pull configuration for differential amplification, so that all amplification stages have a push-pull configuration.
Moreover, the direct connection amplifier which does not have an input capacitor is constituted by measuring the stability by adopting the DC servo system by IC.
The high-level amplifier part of the preamplifier has a configuration in which the input is a buffer with dual FETs, the next stage is differential amplification with an operational amplifier, and the final stage is wideband complementary push-pull.
While eliminating the input capacitor by FET input, the coupling capacitor of the output is also removed by the DC servo system, and the complete direct connection circuit is constructed from input to output.
In the equalizer amplifier section, the input is composed of a FET buffer and the direct coupling input from which the coupling capacitor is removed is formed. When the mirror effect occurs at this stage, the frequency characteristic of the amplifier itself changes due to the inductance of the cartridge and the stray capacity, and the original sound quality of the cartridge is distorted. To prevent this, the E-301 uses a Miller effect canceling circuit in combination with the FET input.
Next to the FET, it passes through differential amplification and is amplified by Darlington, and the final stage is composed of a complementary push-pull circuit.
The whole circuit is stabilized by the DC servo system, the output capacitor is also removed, and it is constituted by the complete direct connection system from DISC(MM) to the output stage of the power amplifier.
Moreover, the disk impedance switch which switches the input impedance at the time of MM is carried.
The head amplifier part has an ICL direct connection type differential push-pull with no capacitor input, and the output stage has a complete push-pull configuration of complementary push-pull. Furthermore, the outstanding S/N is obtained by the low noise element and the low impedance of the circuit.
In order to suppress the interference between unit amplifiers and keep the power supply impedance low over a wide band, a multiple power supply method is used in which a dedicated independent constant voltage power supply is placed in each circuit of the high level amplifier, equalizer amplifier, and head amplifier. It is adopted.
These are arranged in each circuit board, and the element is supplied with the voltage in the shortest distance.
The tone control which provided the turnover changeover switch is carried.
The turnover frequency can be switched between high and low in two steps, and an on-off switch for canceling tone control is also installed.
It is equipped with a loudness compensator that automatically corrects the audibility at low volumes and adjusts the energy balance.
You can select two types of correction curves, and you can enjoy powerful playback sound even at low volume.
The subsonic filter is carried in order to prevent cross modulation distortion by a super-low-pass noise.
The -20dB attenuator switch, the mode switch which changes a stereo / mono, the headphone jack, and the speaker change switch are carried.
There was a cabinet of natural rosewood finish sold separately.
|Model||Integrated stereo amplifier|
| Continuous average output (new IHF, both channel operation,
(20Hz to 20kHz, distortion rate 0.02% or less)
| Total harmonic distortion (new IHF, both channel operation,
0.25W ~ rated output, 20Hz ~ 20kHz)
|IM distortion (new IHF)||0.005%|
|Frequency characteristics (new IHF)||
|Damping factor (new IHF)||80 (8Ω, 50Hz)|
(rated output/new IHF1W output)
|Disc MM(Head amp off):2.3mV/0.22mV/100, 47k, 82k, 150kΩ
Disc MC(Head amp on): 0.12mV/0.011mV/100Ω
Tuner, Aux, Tape play:145mV/13.9mV/47kΩ
Main amp input:1.2V/0.12V/47kΩ
|Disc maximum input (1kHz, distortion 0.01%)||Head amp off:300mVrms
Head amp on:15mVrms
|Rated output/output impedance||Pre output:1.2V/200Ω
Tape rec output: 145mV/200Ω (at disc input)
Headphones: 0.32V, conforming impedance: 4-32Ω
|Gain||Main input → Output:27.8dB
High Level input → Pre output: 18.4dB
Disc input(Head amp off) → Tape rec output:36dB
Disc input(Head amp on) → Tape rec output:62dB
|S/N, input conversion noise||
|Tone control||10 step control
Comp 2: +10dB(50Hz), +6dB(20kHz)
|Subsonic filter||17Hz, -12dB/oct|
|Semiconductor used|| Transistor: 81 pieces
FET: 20 pieces
IC: 13 pieces
Diode: 83 pieces
|power supply||AC100V/117V/220V/240V, 50Hz/60Hz|
|Power consumption||60W (without input)
400W (at rated output of 8Ω)
|Outer dimensions||Width 445 x height 160 (including legs) x depth 370 mm
Wood cabinet: width 466 x height 190 (including legs) x depth 385 mm
|Sold separately||Wood cabinet A-8 (¥16,000)|