m Revolutionar y AAVA volume control m Fully modular
construction with individual left/right amplifier units arranged onmotherboard m Separate power transformers and filtering
capacitors for left and right channels m Logic-controlled relays
for shortest signal paths m High quality tone controls m Option
board slots allow digital signal input and analog record playback

Innovative AAVA type volume control Adjusts listening level without
deterioration in S/N ratio or distortion. Dual mono construction with two powertransformers and separate modular AAVA amplifiers for left and right channels
mounted on motherboard. Option board slots provide support for digital input
signals and high-grade analog record playback.
The C-2000 inherits the design technology of
the Accuphase C-2800 and C-2400, featuring
the same AAVA type volume control. AAVA
(Accuphase Analog Vari-gain Amplifier) is aninnovative concept that differs radically fromconventional variable-resistor type volumecontrols. It tackles one of the most important
aspects of a preamplifier, namely how it handles
listening level adjustment.
In AAVA, amplification and volume control are
fully unified, eliminating all mechanical contact
points. Pure analog processing ensures
optimum performance and superb sound. Doing
away with the variable resistor in the signal pathhas numerous advantages and brings thethe two channels, arranged on a high-quality
motherboard. This fully monophonic construction
prevents unwanted interaction both on theelectrical and the physical plane.
The line amplifier with integrated volume control
is a major aspect of the C-2000, but there arealso a host of other attractive features in thissuperb analog preamplifier. Tone controls andloudness compensator allow fine tuning of thesound. Tape recorder and copying facilities aswell as an EXT PRE function provide
connection flexibility. A range of option boards
allows the amplifier to handle digital input
signals and to realize high-grade playback ofanalog records.

amplifier a significant step closer to absolutepurity in signal transmission. Another benefit of
AAVA is that it is configured only with highly
reliable semiconductor components. Thisassures that performance and sound quality willremain undiminished for many years to come.
The large volume knob on the front panel
employs a position detection method thatcombines superb precision with a smoothconventional feel.
The power transformer, filtering capacitors andall other parts of the power supply are duplicatedfor the left and right channel. What's more, allunit amplifiers such as for line input, balanced
output, and AAVA are also entirely separate for

AAVA (Accuphase Analog Vari-gain Amplifier) volume control
The newly developed volume control called AAVA (Accuphase Analog Vari-gain Amplifier) is totally different from conventional controls using
resistors. Because the music signal does not pass through variable resistors, it is not affected by changes in impedance. This means that highsignal-to-noise ratio and low distortion of the signal are maintained. The volume can be adjusted without any deterioration in sound quality.
n Volume control resolution
AAVA adjusts the listening volume by means of 16 current
switches which are operated by 16 weighted V-I converter
amplifiers. The number of possible volume steps set by
the combination of these converter amplifiers is 2 to thepower of 16 = 65,536.
n AAVA maintains high S/N ratio and unchanged
frequency response
With conventional volume controls, the impedance
increases significantly at settings that correspond to normal
listening levels, thereby leading to increased noise.
Because there is no change in impedance with AAVA, there
is no deterioration of S/N ratio, and frequency response
also is not affected. Adjusting the volume with AAVA does
not mean introducing noise. High S/N ratio is maintained,
and there is no alteration of sound quality.
n No more left/right tracking differences or crosstalk
Because AAVA is an electronic circuit employing fixedvalue resistors, there is virtually no left/right tracking error
also at low volume levels. Since channels can be kept
separate, crosstalk also does not present a problem.
n Simple circuit configuration
AAVA unifies the amplifier and volume control functions,
resulting in a circuit that is electrically very simple. Longterm reliability is excellent, with performance and soundquality that will remain unchanged also after prolonged
use.
n AAVA means analog processing
The AAVA circuit converts the music signal from a voltage
into a current, switches gain by means of current switches,
and then reconverts the current into a voltage. The entire
process is carried out in the analog domain.
n Same operation feel as a conventional high-quality
volume control
The volume control knob position is detected by a
dedicated CPU which in turn selects the current switches
for AAVA operation. Operating the knob therefore feels
exactly the same as with a conventional control, and as
before, operation via the remote commander is also
possible.
n Attenuator and balance control also implemented byAAVAThe functions of the attenuator and the left/right balance
control are covered by the AAVA circuit as well, eliminating
the need for additional circuit stages. Keeping theconfiguration simple helps to maintain high performanceand sonic purity.

16 current switches(65,536 possible combinations)

AAVA principle

I-V Converter

BUFFER

Reconversion ofcurrent into voltage

INPUT
BUFFEROUTPUT

Input musicsignalCurrent values
are added

VOLUME
54CPU

V- 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 position

6371928MINMAX

Volume knob isturned and position isdetected

AAVA operationAAVA operates by feeding the music signal to a V-I (voltage - current) converting amplifier
where it is weighted in 16 steps [1/2, 1/22, ... 1/215, 1/216]. The 16 current steps are turnedon or off by 16 current switches, and the combination of switch settings determines theoverall volume. The switching operation is controlled by a CPU according to the position 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 voltage by anI-V (current - voltage) converter.

Modular AAVA unit contains
input buffer, 16 V-I converter
amps and current switches,current adder, I-V converter
amp, and other circuitry on
three boards, plus a CPU for
AAVA control. Modules are
installed separately for left/right channel on a motherboard.

Logic-controlled relays assure high soundquality and long-term reliability

Tone controls use summing active filters forhighest sound quality

The C-2000 offers a host of input and output
connectors and functions. Strategically placed
relays allow straight and short signal paths, toprevent degradation that could occur if the signal
had to travel long distances for connection andfunction switching.

The tone control circuitry in the C-2000 uses
summing active filters. The illustration below shows
the operation principle of this circuit. The flat signal
is passed straight through, and only when anadjustment is required, the characteristics arecreated at F1 and F2 and added to the signal,
thereby producing the desired change. This design

provides efficient control without degrading signal
purity. The turnover frequency for the bass control(max. ±8 dB) can be switched between 40 and100 Hz, and that for the treble control (max. ±8dB) between 8 kHz and 20 kHz.

16BASS– A2

F1VR1Output

TREBLE
100Hz40Hz

128kHz20kHz

8Response in dBInput–A 1

40–4
–8

F2
–12Dual mono construction with separate powertransformers and separate board-mounted
unit amplifiers for left/right
The input buffer, AAVA circuit, balanced output
and other amplifier circuitry are configured asfive separate units for each channel, arranged
neatly on a motherboard. Power transformers andsmoothing capacitors are also separate for thetwo stereo channels. This thorough dualmonophonic approach assures total freedom
from unwanted mutual interaction.

n Supplied remote commander RC-20
Allows volume control
and input source
selection.

VR2

Tone control circuit principle(using summing active filters)

–16
10100

1k
Frequency in Hz

10k

100k

Tone control characteristics

Option Boards

Other features and functionsn Flexible input/output configurationn Dedicated headphone amplifier optimized forhigh sound quality
n EXT PRE function allows use of external
preamplifiern Option board slots allow digital signal input andplayback of analog records
n Supplied remote commander with volumecontrol functionn Versatile features:• Recording/playback/monitoring facilities for 2recorders with copy function• Phase selector• Attenuator• Loudness compensator for rich bass at low levels

Digital Input Board

Three types of option boards are available for theC-2000: Digital Input Board DAC-10, Analog Disc Input
Board AD-10, and Line Input Board LINE-10. Insert thedesired board in a rear-panel option board slot.
• You can also install two identical boards.
• The Analog Disc Input Board AD-9 and the Line Input
Board LINE-9 can also be used.
• The DAC-10 cannot be used in the models E-407,E-406V, E-306V, E-211, and C-265.

DAC-10This board features an MDS (Multiple Delta Sigma)
D/A converter. It can accept the digital output signal
from components such as a CD player, MD recorder,
DAT recorder, etc. (sampling frequency range 32 - 96
kHz, 24 bits) for high-grade music reproduction.
• Inputs for coaxial and optical fiber connections areprovided.

Analog Disc Input Board

AD-10

This board contains a high-performance, high-gain
phono equalizer.
• Internal DIP switches control MM/MC operation, MC input
impedance, and subsonic filter on/off.

Response in dB

LOUDNESS COMPENSATOR : ONMM

Gain:
36 dB
Input impedance: 47 kilohms

MCGain:Input impedance:

62 dB
10/30/100 ohms (selectable)

Line Input Board
AD-10
DAC-10Frequency in Hz

Compensator characteristics

LINE-10

This option board provides an additional set of
conventional unbalanced line inputs which can be used
to connect a CD player, tuner, or other component withanalog outputs.

Photograph shows an example of option board installation.

n Front panel

GUARANTEED SPECIFICATIONS[Guaranteed specifications are measured according to EIA standard RS-490.]m Frequency Response

BALANCED/UNBALANCED INPUT
03 - 200,000 Hz+0, –3.0 dB
20 - 20,000 Hz+0, –0.2 dB

m Total Harmonic Distortion

0.005% (for all inputs)

m Input Sensitivity, Input Impedance
Input

BALANCEDUNBALANCED

Sensitivity
For rated output
For 0.5 V output
252 mV63 mV
252 mV
63 mV

m Rated Output Voltage,Output Impedance

40 kΩ
20 kΩ

BALANCED/UNBALANCED OUTPUT:
2 V,
RECORDER REC:
252 mV,

50 ohms
200 ohms

m S/N Ration Rear panel

Input
Option board slots
BALANCEDUNBALANCED★
A Input selector
LINE 2 LINE 1 LINE-BAL CD-BAL CD
TUNER OPTION 1 OPTION 2
B Function LED indicators
C Volume control
D Power switch
E Output selector
EXT PRE ALL BAL UNBAL OFF
F BASS and TREBLE controls
G Phase selector button
H Tone control buttons
ON/OFF 40/100 Hz 8 kHz/20 kHz
I Stereo/mono selector button
J Loudness compensator button
K Copy selector
1➞2 OFF 2➞1

L Recorder selector
REC OFF SOURCE 1 2
M Balance control
N Headphone jack
O Attenuator button
P Line input connectors TUNER CD LINE 1,2
Q Recorder playback/recording connectors
R Unbalanced output connectors (2 sets)
S External preamplifier input connectors(unbalanced)
T CD/LINE balanced input connectors
a Ground b Inverted (–)
c Non-inverted (+)
21 Balanced output connectors
U
22 External preamplifier input connectors (balanced)
U
23 AC power supply connector★
URemarks★ This product is available in versions for 120/230 V AC. Make sure that the voltage shown on the rearpanel 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 anddestination country.

n Supplied accessories:

Inputimpedance

Input shorted (A weighting)
S/N ratio at rated output
108 dB108 dBEIA S/N
107 dB
107 dBm Maximum Output Level (0.005% THD, 20 - 20,000 Hz)
BALANCED/UNBALANCED OUTPUT:
RECORDER REC:

7.0 V
6.0 V

m Minimum Load Impedance BALANCED/UNBALANCED OUTPUT:
RECORDER REC:

600 ohms
10 kilohms

m GainBALANCED/UNBALANCED INPUT ➞ BALANCED/UNBALANCED OUTPUT:
BALANCED/UNBALANCED INPUT ➞ REC OUTPUT:

18 dB
10 dB

m Tone Controls

Turnover frequeAncy and adjustment range
BASS:
40/100 Hzswitchable,
TREBLE: 8 kHz/20 kHz switchable,m Loudness Compensation+6 dB (100 Hz)

m Attenuator–20 dBm Headphone Jack

Suitable impedance:m Power Requirements

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

±8 dB
±8 dB

8 - 100 ohms

m Power Consumption

30 Watts

m Maximum Dimensions

Width 465 mm (18-11/16")
Height 150 mm (6-3/4")
Depth 405 mm (16-5/8")

m Mass

16.2 kg (35.7 lbs) net
20.0 kg (44.1 lbs) in shipping carton

m Supplied Remote Commander RC-20
Remote control principle: Infrared pulse
Power supply:
3 V DC (IEC R6 batteries × 2)
Maximum dimensions:
55 mm (W) × 194 (H) × 18 (D) mm
Mass:
100 g (including batteries)• AC power cord
• Audio cables with RCA-type plugs (1 m)• Remote Commander RC-20• Specifications and design subject to change without notice for improvements.

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