m Revolutionary AAVA-II volume control m Parallel push-pull
output stage with high-power transistors delivers plenty of quality
power m Instrumentation amplifier principle enhances current
feedback and MCS+ topology in power amplifier section m Logiccontrol relays for straight and short signal paths m Robust power
supply with large toroidal transformer and high filtering capacity

High-class integrated amplifier with 180 watts per channel (8 ohms) – Innovative AAVA-II volume control opens up new musical frontiers. High-powertransistors operate in a parallel push-pull arrangement. Power supply withlarge, highly efficient toroidal transformer and oversized filtering capacitors
sustains ample power. Instrumentation amplifier configuration in power amplifier makes optimum use of current feedback design combined with further improved MCS+ topology, resulting in excellent high-range phase characteristics.
The E-450 succeeds the highly popular andsuccessful Accuphase model E-408. It reflects
latest research breakthroughs and features
the innovative AAVA-II volume control principle. Only top-quality parts are used throughout
its sophisticated circuitry. The overall result isan integrated amplifier that brings out eventhe most delicate nuances in the music withbreathtaking immediacy.
The AAVA volume control principle developedby Accuphase totally revolutionizes the waythat the listening volume is adjusted. However,in its initial form, AAVA required a considerable amount of physical space. With AAVA-II,
Accuphase has now taken this principle to thenext level, delivering the same peerless performance in a more compact form factor. Thiswas made possible by implementing highlysophisticated surface mount technology while
increasing component density and integrationand optimizing the layout. With AAVA-II, amplification and volume control are fully integrated.
The use of highly reliable electronic components eliminates mechanical wear and associated problems, allowing the control to function
perfectly for many years.
Because an integrated amplifier has very highoverall gain, even the slightest interference or
crosstalk at the input can have a considerable
effect on the signal provided at the output. To
preclude this possibility, the E-450 is built withtotally separate preamplifier and power amplifier sections. Both electrically and structurally,
these two parts operate completely autonomously. A set of EXT PRE inputs and outputs
allows using the preamplifier and power amplifier separately. In terms of performance quality,
the E-450 can hold its own even when compared with stand-alone components.
The power amplifier section is built as anadvanced instrumentation amplifier, whichenables fully balanced signal transmission
throughout. Together with further improved
MCS+ circuit topology and the highly acclaimed current feedback principle, this makesfor even better electrical characteristics. In theoutput stage, high-power transistors designed
for audio applications are arranged in a parallelpush-pull configuration, greatly improving thecapability of the amplifier to drive low impedance loads.

n Parallel push-pull power amplifier unit achieves 180 watts
per channel into 8 ohms or 260 watts into 4 ohms.

The output stage devices feature excellent frequency response, current
amplification linearity, and switching characteristics. These high-powertransistors have a rated collector dissipation of 220 watts.

n Instrumentation amplifier principle in power amplifier section

allows fully balanced signal paths. Current feedback design
ensures outstanding high-range phase characteristics together with further
improved MCS+ topology.

High-power transistorsn Massive high-efficiency toroidal transformer and large filtering capacitor
selected for sound quality provide ample reserves.

n Logic-controlled relays assure high sound quality and long-term reliability.
n Tone controls using active filters for optimum sound quality.
n Loudness compensator for enhanced bass at low listening
levels.

Toroidal power transformern E-450 front panel switching enables MC/MM selection for
optional Analog Disc Input Board AD-20.

n “EXT PRE” button and preamplifier output/power amplifier

input connectors allow independent use of preamplifier andpower amplifier sections.

n Dedicated headphone amplifier delivers audiophile quality
sound.

“MC/MM” Selectorn Analog peak power meters for monitoring output levels.
“EXT PRE” buttonn Two sets of large-size speaker terminals.
n “High Carbon” cast iron insulator feet further enhance sonic

Filtering capacitors

purity.

n Versatile array of inputs with balanced connectors to shut out externalnoise interference.

Large speaker terminals

Unbalanced input/output jacks and balanced input connectors

High-reliability parts selected for sound quality

MCS+ (Multiple Circuit Summing-up)
Biasstabilizer+B 3
REGULATOR+ B1

Q1
Q5

Q9

Q 13

Q7Q 11

Q 15+ B2
Q 17+–Q3NFB
NETWORK

Q 19

Q 21

Q 23

Bias
stabilizer

INPUT

OUTPUTNFBNETWORKBiasstabilizer

Biasstabilizer

NFB
NETWORK

Q2–+Q6Q 10

Q 14

Q8Q 12Q 16Q 18

Q 20

Q 22

Q 24– B2Q4

REGULATOR– B1– B3Biasstabilizer

Circuit diagram of E-450 power amplifier(one channel)

n Output stage and power amplifier assemblywith parallel push-pull devices, MCS+ circuitand current feedback circuitry mounted tolarge heat sink

AAVA-II (Accuphase Analog Vari-gain Amplifier) type volume control
AAVA-II (Accuphase Analog Vari-gain Amplifier) is a totally new volume control concept that completely does away with variable resistors in the signal path.
Because the music signal does not have to pass through such devices, there is no adverse influence from changes in impedance. This means that the outstanding
S/N ratio and low distortion of the amplifier are not compromised in any way, and the same superb sound quality will be obtained at any volume setting.

n AAVA-II input stage employs current feedback

sound quality that will remain unchanged also after prolonged
use.

principle that ensures high-speed, low-noise
operation and assures excellent characteristics
at high output voltages.
n Volume control resolution.

n AAVA-II means analog processing.

The listening volume is adjusted by a combination of 16 V-I
converters. The number of possible volume steps is 2 to thepower of 16 = 65,536, as determined by current switches.

The AAVA-II circuit converts the music signal from a voltage
into a current, to allow control by current switches, and thenback into a voltage. The entire process is carried out in theanalog domain.

n No more left/right tracking differences orn Control knob gives same operation feel as with

Because AAVA-II is an electronic circuit employing only fixed-value
resistors, there is virtually no left/right tracking error also at low
volume levels, and crosstalk also does not present a problem.

n Attenuator and balance control also imple-crosstalk.

Because AAVA-II employs circuitry that is electrically very
simple, long-term reliability is excellent, with performance and16 current switches(65,536 possible combinations)

Reconversion of current
into voltage+AMP.

Current
values areadded–FEEDBACK
NETWORKa conventional high-quality volume control.
mented by AAVA-II.

How AAVA-II works

I-V Converter

Current feedback
amplifier

INPUT

frequency response.

Because AAVA-II does not introduce any change in impedance,
there is no deterioration of S/N ratio or alteration of frequency
response. Changing the volume with AAVA does not mean
introducing noise or otherwise degrading the sound quality ofthe amplifier.

n AAVA-II circuitry is deceptively simple.

AAVA-II
operation
principle

n AAVA-II maintains high S/N ratio and uniform

OUTPUT

AAVA-II operates by feeding the music signal to a V-I (voltage - current) converting amplifier where it is weighted in 16steps [1/2, 1/22 , ..., 1/215 , 1/216 ]. The 16 current steps areturned on or off by 16 current switches, and the combination of switch settings determines the overall volume. Theswitching operation is controlled by a CPU according to theposition of the volume control knob. The combined signal
current forms a variable gain circuit that adjusts the volume.
Finally, the combined current is converted back into a musicsignal voltage by an I-V (current - voltage) converter.

Volume knob is turnedand position is detectedn AAVA-II volume control assembly

CPUV-I Converter
Conversion into current
with 16 weighting stages(1/2~1/216 )VolumeBalance
Attenuator

CPU detects position of volume knob
and operates current on/off switches
according to knob positionn Supplied remote commander RC-200
Allows volume adjustment and input
source switchingwith higher integration densityof components andcircuitry

Option Boardsn Tone controls using summing active
filters for optimum sound quality

–A1

Input

–A2

OutputDigital Input Board

Three types of option boards can be used in the E-450:
the Digital Input Board DAC-20, Analog Disc Input Board
AD-20, and Line Input Board LINE-10. These boards canbe installed in the rear-panel slots as required.
m It is possible to install two identical boards.

F1m The Analog Disc Input Board AD-9/AD-10 and the Line Input
Board LINE-9 can also be used.

VR1m When using the AD-9/AD-10, the MC/MM button of the E-450
has no effect. MC/MM switching must be performed on theboard.

F2
VR2

Tone control circuit principlen Loudness compensator for enhancedm Inputs for coaxial and optical fiber connections are provided.

Analog Disc Input Board

AD-20

This board serves for playback of analog records.
It contains a high-performance, high-gain phonoequalizer.
m MC/MM switching is possible on the front panel of theE-450.
m Internal DIP switches control MC input impedance andsubsonic filter on/off.

bass at low listening levels
1816

Gain: 62 dB

MC Input impedance : 10/30/100 ohms (selectable)

1412DAC-20

The board features an MDS (Multiple Delta Sigma) ++type D/A converter and allows direct digital connection of a CD player, MD or DAT recorder or othercomponent with digital output (sampling frequency
up to 96 kHz, 24 bits), for high-quality music reproduction.

LOUDNESS COMPENSATOR: ON

10: 36 dBMM GainInput impedance : 47 kilohms

Response in dB

86420

Line Input Board–2–4

AD-20–610100

1k
Frequency in Hz

10k100k

DAC-20Compensator characteristics

Photo shows
an example for option
board installation.

n Front Panel

LINE-10

This option board provides an additional set of unbalanced line inputs.

GUARANTEED SPECIFICATIONS[Guaranteed specifications are measured according to EIA standard RS-490.]m Continuous Average Output Power (both channels driven, 20–20,000 Hz)
260 watts per channel into 4 ohms
1220 watts per channel into 6 ohms
1180 watts per channel into 8 ohms
m Total Harmonic Distortion(both channels driven, 20–20,000 Hz)
0.05%
with 4 to 16-ohm loadm Intermodulation Distortion 0.01%
m Frequency Response
HIGH LEVEL INPUT/POWER IN
20 – 20,000 Hz +0, –0.2 dB (for rated continuous average output)
3 – 150,000 Hz +0, –3.0 dB (for 1 watt output)m Damping Factor

120 (with 8-ohm load, 50 Hz)

m Input Sensitivity, Input ImpedanceSensitivity
Input
For rated output For 1 W output (EIA) impedanceHIGH LEVEL INPUT
190 mV14.2 mV
20 kΩ
BALANCED INPUT
190 mV14.2 mV
40 kΩ
POWER IN
1.51 V113 mV
20 kΩ
InputPressing this button
opens the sub panel.

n Rear Panel
Option board
installation
slots

m Output Voltage, Output Impedance
PRE OUTPUT:
1.51 V, 50 ohms
(at rated continuous average output)
m GainHIGH LEVEL INPUT → PRE OUTPUT:→ OUTPUT:POWER INm Tone Controls

18 dB
28 dB

Turnover frequency and adjustment range
BASS:
300 Hz±10 dB(50 Hz)TREBLE: 3 kHz±10 dB(20 kHz)m Loudness Compensation+6 dB (100 Hz)

m Attenuator–20 dBm Signal-to-Noise Ratio (input-converted noise)
Input shorted (A weighting)
S/N ratio at rated output
HIGH LEVEL INPUT
110 dBBALANCED INPUT
93 dB
POWER IN
123 dB
Input

Input selector
LINE 2 LINE 1 LINE-BAL CD-BAL CD
TUNER OPTION 1 OPTION 2
Left/right channel output meters
Function indicator LEDs
Volume control
Power switch
Speaker selector OFF A
B
A+B
Copy selector
1→2
OFF
2→1
Recording output selector REC OFF, SOURCE 1, 2
Function buttons
MC/MM, EXT PRE, MONO/STEREO, Meter ON/OFF
Compensator ON/OFF, Tone Control ON/OFF

Bass control
Treble control
Balance control
Attenuator button
Headphone jackLine inputs (unbalanced)
Recorder inputs and outputs
Left/right speaker output terminals A/B
CD/LINE inputs (balanced)
Preamplifier outputs
Power amplifier inputs
Switched AC outlet

EIA S/N
92 dB
92 dB
100 dBm Power Level Meters

Logarithmic compression, peak reading meters
Output dB/% scale

m Load Impedance

4–16 ohms

m Stereo Headphones

Suitable impedance:m Power Requirements

AC 120 V/230 V 50/60 Hz(Voltage as indicated on rear panel)m Power Consumption

60 watts idle
450 watts in accordance with IEC 60065

m Maximum Dimensions

WidthHeightDepthm Mass24.4 kg (53.8 lbs) net
30.0 kg (66.1 lbs) in shipping carton

465 mm
181 mm
427 mm8–100 ohms

(18-5/16”)(7-1/8”)(16-13/16”)

m Supplied Remote Commander RC-200
Remote control principle: Infrared pulse
Power supply:
3 V DC (IEC R03 batteries × 2)
Maximum dimensions:
56 mm × 175 mm × 26 mm
Mass:
153 g (including batteries)

Remarks
This product is available in versions for 120/230 V AC. Make sure that the voltage shown on the rear panel matches the AC line voltage in your area.
The shape of the AC inlet and plug of the supplied power cord depends on the voltage rating and destination country.

n Supplied accessories:m AC power cordm Remote Commander RC-200m

Specifications and design subject to change without notice for improvements.

http://www.accuphase.comC0705Y

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