Since the E-303 launching in 1978, the high-power
integrated amp is at the core of Accuphase productlineup.
E-480 is a succession model of E-470, it is the 11th
generation of “Accuphase Core Product”.
Preamplifier section features the further evolved AAVA
that enables an accurate volume control.
At power amplifier section, a damping factor is further
enhanced with precise and dynamic speaker driving
ability.
The preamplifier and power amplifier sections are kept
entirely separate, users are able to combine E-480 withother separate systems.

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The new E-480 is a new-generation integrated amplifierthat comes close to the performance of separate system.

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E-480 has a wholly new front panel design including thebutton array inside the subpanel.
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-480 takes the mono block construction. With thesymmetrical arrangement of L / R power amplifier blocks,
strong power supply with a massive high-efficiency
toroidal transformer and two large 40000μF speciallymade filtering capacitors are installed at the center of unit.
AAVA circuit block is located near the front panel.

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The rated output power of E-480 is 180W into 8Ω load,
260W into 4Ω load. The actual maximum output power
achieves 290W into 4Ω load.
These output power figures are same as former model E470.

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E-480 marks 4.7μV of the actual noise voltage.
This is 10% lower(1dB) than the former model E-470.
E-480 guarantees 109dB Signal to Noise ratio at themaximum gain.

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The AAVA(Accuphase Analog Vari-gain Amplifier) is a
volume control principle that eliminates all variable
resistors from the signal path. This is Accuphase uniquetechnology.
The AAVA module in E-480 achieves low noise by thefourth paralleled 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.
* The AAVA module in the former model E-470 has
paralleled the largest two units in “V to I” converters.

6E-480 guarantees 600 of Damping Factor.
It is 20% higher than the former model E-470.
**Damping Factor:
A index of speaker driving ability.
Higher Damping Factor amplifier has higher speakerdriving ability.
D.F. = 8Ω / Output-impedance7Power amplifier sections contain same circuit
configuration as Class-A stereo power amp. A-75.
The output impedance is decreased by 3 parallel pushpull final stage arrangement of MOS-FETs.
E-480 mounts the new power MOS-FET device which isheavy-duty and has the large absolute maximum ratings.
**Absolute maximum ratings of power MOS-FET
E-470’s MOS-FET: 180V / 10A
E-480’s MOS-FET: 200V / 12A

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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 ofGND level.
Not only Damping Factor, but also Total Harmonic
Distortion and Intermodulation Distortion are all improvedby the Balanced Remote Sensing.

9Although a mechanical relay is the most popular
component for speaker protection, it does not have highreliability and low contact resistance either.
E-480 applies a MOS-FET switch instead of mechanicalrelay for speaker protection.
Damping-Factor, reliability and sound quality are all
improved by MOS-FET switch.
E-480 was adopted a new MOS-FET which has very low
on resistance of 2.0mΩ. (E-470 used 2.6mΩ onresistance MOS-FET)
By connecting speaker terminals and PC-board directly,
signal path can be made shorter to obtain the lowimpedance.

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To enhance the further product safety and reliability, E480 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-470: 1 sensor on chassis only). Thanks to this,the unit accurately ascertains the high temperature alarmin 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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When embarking on the design of a product, we have acertain concept of the sound that we want to achieve,
and this guides us in deciding on circuit topology, parts
selection, and physical construction. But in many cases,
it will not be possible to realize the original sonic concept
right away.
By changing the combination of parts, their physicallayout, and various other factors, we adjust the soundand work towards bringing it closer to our goal.
Accuphase engineers devoted much time to do repeatedlistening test for the technical development.
The picture shows a few examples of trial parts during E480 development.

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