2015-launched E-370 was highly praised in the high-end
audio market with superb performance, outstanding reliability
and delightful sound quality with authentic musicality.
E-380 is a succession model of E-370, it achieves 20%
enhanced output power by strong power supply andamplification stage.
The pre-amplifier section features the further evolved AAVA
that reenacts the details of music source.
At the power amplifier section, the damping factor is further
enhanced with precise and dynamic speaker driving ability.
The pre-amplifier and power amplifier sections are entirelyseparated, you are able to connect E-380 with otherseparated systems.
The mega-evolved E-380 surely takes audiophiles to a worldof unlimited musical enjoyment.

1E-380 has a wholly new front panel design including thebutton array inside the subpanel.
The needle power meter with indication range to -50dB isable to move even at the small volume level less than 60dB.
Sampling Frequency Display has expanded to “MHz” tosupport the DAC-50.

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E-380 takes the mono block construction.
With the symmetrical arrangement of L / R power
amplifier blocks, the strong power supply with a massivehigh-efficiency transformer and two large 33000μF
specially-made filtering capacitors are installed at thecenter of unit.
AAVA circuit block is located near the front panel.

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The rated output power of E-380 is 20% higher than theformer model due to the enhanced power supply section.
They are 120W into 8Ω load and 180W into 4Ω load.

4E-380 marks 4.2μV of the actual noise voltage.
This is 20% lower(2dB) than the former model.
E-380 guarantees 109dB Signal to Noise ratio at themaximum gain.

5AAVA(Accuphase Analog Vari-gain Amplifier) is a volume
control principle that eliminates all variable resistors fromthe signal path. This is the original Accuphase unique
technology.
AAVA module in E-380 achieves low noise by the fourthparalleled largest unit and the paralleled second largest
unit in “V to I” converters.
This improvement helps to make the V-I converter amp’s
output current double, and it results in reducing the valueof the feedback resistors and the noise coming fromthem.
*AAVA module in the former model E-370 has paralleled
the largest two units in “V to I” converters.

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Left and right channels are symmetrically arranged in
AAVA assembly of E-380.

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E-380 guarantees 500 of Damping Factor.
It is 25% higher than the former model.
**Damping Factor:
An index of speaker driving ability.
Higher Damping Factor amplifier has higher speakerdriving ability.
D.F. = 8Ω / Output-impedance8Same as other Accuphase self-standing power amplifiers,
E-380 applies “Instrumentation Amplifier principle” for its
power amplifier section.
The output impedance of power amplifier is decreasedby the parallel push-pull final stage arrangement of highoutput current with high linearity bipolar transistor.
E-380 has the new bipolar transistor which is heavy-duty
and has the large absolute maximum ratings.
**Absolute maximum ratings of bipolar transistor on finalstage
E-370’s transistor: 150V / 10A
E-380’s transistor: 160V / 15A

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Remote Sensing is the technique to lower the output
impedance of amplifier by the negative feedback withsignal sensing from nearby the speaker terminals.
Balanced Remote Sensing is the technique to make theoutput impedance even lower by both the signal sensing
and the GND sensing, that is the negative feedback of
GND level.
Not only Damping Factor, but also Total Harmonic
Distortion and Intermodulation Distortion are all improvedby the Balanced Remote Sensing.

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Although a mechanical relay is the most popular
component for speaker protection, it does not have highreliability and low contact resistance either.
E-380 applies a MOS-FET switch instead of mechanicalrelay for speaker protection.
Damping-Factor, reliability and sound quality are all
improved by MOS-FET switch.
MOS-FETs in E-380 are as same as the ones in A-250.
They have very low on-resistance of 2.0mΩ.
**MOS-FET in E-370 is 2.6mΩ on-resistance.
By connecting speaker terminals and PC-board directly,
the signal path can be made shorter to obtain the low
impedance.

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To enhance the further product safety and reliability, E380 improves the protection circuit on Power amplifier
section.
・Newly-developed protection circuit
Over current protection circuit using photo-coupler isapplied, it does not affect the sound quality at all.
・Temperature-sensor
Temperature-sensors which detects the heat sinktemperature are installed on L / R both heat sinks one byone (E-370: 1 sensor on chassis only).
Thanks to this, the unit accurately ascertains the hightemperature alarm in power amplifier section.
**When these protection circuits are activate, the unit
completely interrupts speaker output and makes thepower meters flash to indicate an abnormal condition.

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