PRECISION STEREO PREAMPLIFIER● Balanced A AVA volume control ● Quiet and smooth volume sensor
construction ● Separate unit amplifiers for left and right ● Separate toroidaltransformers for left and right ● Newly developed filtering capacitors● Printed circuit boards using glass cloth fluorocarbon resin ● Woodcabinet with natural grain finish ● High-performance headphone amplifier

Balanced AAVA preamplifier with exquisite sound reproduction
The preamplifier’s volume control is a vital component for maintaining vibrancy in the sound source.
Since its founding, Accuphase has spent 50 years in pursuit of creating the ideal volume control circuitry.
The C-2900’s Balanced AAVA system was designed using Accuphase's original AAVA volume control
circuits to significantly improve sonic performance. The faithful reproduction of delicate musicalperformances by the C-2900 makes it the perfect preamplifier for passionate audiophiles.

Innovation – The leading edge of technology■ Balanced volume control, Balanced AAVA
Conventional preamplifiers use variable resistors to adjust volume, which creates
grit, causes contacts to deteriorate, and increases noise at normal volume levels.
AAVA, however, produces multiple, widely varying signals from the input signal
and controls volume by changing the combination of those signals. This achieves
minimum noise levels at all volume levels without any grit. The Balanced AAVA
principle utilizes two balanced-connection AAVA circuits and reduces noise levelsin the C-2900 roughly 20 % over conventional preamplifiers.

＋＋−
Balanced
input−＋−

AAVA

＋−
AAVA

Balanced
outputConventionalmodels

20 %C-2900

Balanced AAVA on circuit boards using glass cloth fluorocarbon resin

Noise level

Balanced AAVA

■ Quiet and smooth volume sensor design
The volume sensor detects the angular position of the volume knob and transmits
it to the AAVA circuitry. Accuphase developed this volume sensor in-house, using
an aluminum block extrusion process to achieve an utterly smooth and solid
operation feel and extremely accurate position detection. Operation sounds
are minimal even when using the Remote Commander to ensure an extremely
quiet and pleasant listening environment.
Volume sensor

Sound quality – In pursuit of the highest quality audio■ Separate unit amplifiers for left and rightMusic signal circuits like the AAVA contain six unitamplifiers for both the left and right channels.
The unit amplifiers on the left and right are housed
in 8mm thick hard aluminum frames to suppress
electrical interference and prevent vibrations fromadversely impacting sound quality.

R chPower supply

Balanced AAVA

Power supply

Balanced AAVA

AD-2900 phonoequalizer unit
(optional)

8mm thick hard aluminum frame■ Independent power supplies for left and right channels
The power source that drives the different circuits can greatly affect soundquality. Both the right and left channels feature a high-quality toroidal transformer
inside a cast-aluminum case equipped with heat dissipation fins. The two newly
developed 10,000 μF high-capacity, high-quality filtering capacitors mounted ineach channel supply plentiful power for unimpeded handling of load fluctuations.

Volume sensor

L chToroidal transformers

Filtering capacitors (10,000 μF × 4 pcs)

Discrete Balanced AAVA circuits for left & rightAdvanced features■ Balanced AAVA volume control■ Logic-controlled relays for signal switching assure high soundquality and long-term reliability■ Printed circuit boards for signal transmission use glass cloth
fluorocarbon resin with low dielectric constant and minimum loss
along with gold-plating on copper foil surfaces■ Power supply circuits with separate toroidal transformers andfiltering capacitors (10,000 μF × 4 pcs) for the left and right■ Newly developed volume sensor construction for a quiet andsmooth operation feel
■ Versatile arrangement of inputs and outputs (five line level inputs, twobalanced inputs, two line level outputs, and two balanced outputs)■ Line level input and output connectors for a recorder■ Line level and balanced EXT PRE inputs for connection of anexternal preamplifier■ Individual phase setting for each input■ Switchable overall gain (12 dB / 18 dB / 24 dB)■ Left / right balance control through Balanced AAVA
■ Stereo signal can be switched to monophonic operation■ Volume attenuator to instantly reduce sound to as low as –20 dB■ Loudness compensator for correcting the perceived spectral balance■ Informative and easy to read input and volume level display withon / off switching■ Discretely configured, high-quality headphone amplifier withparallel push/pull output stages■ Subsonic filter that cuts off ultra-low frequency noise fromrecord warping■ Front panel switching function for using a phono equalizer expansion unit
• MC/MM switching• MC load impedance switching (10 / 30 / 100 / 200 / 300 ohms)• Gain switching (MM: 34 / 40 dB, MC: 64 / 70 dB)■ Natural grain wood case with a mirror finish crafted by artisans using
carefully selected virgin wood
■ High-carbon cast iron insulator feet with superior damping characteristics

❶❼❽

❷❾

■ Supplied RemoteCommanderRC-250❿❹⓫⓬❺❻⓭❶ Output selector for using an external preamplifier and controlling output operation❷ Gain selector for overall system gain
❸ Left / right balance control knob

❹ Loudness compensator for correcting the perceived spectral balance❺ Headphone level selector for switching headphone amplifier gain

❻ Recorder selector for function switching when a recorder is connected❼ Phase selector button for input signal❽ Button for switching stereo signals to a monophonic signal❾ Filter button to prevent ultra-low frequency noise from impacting audible bandwidths
With phono equalizer❿ AD GAIN button for phono equalizer gain switching⓫ MC/MM button for cartridge type switching⓬ MC LOAD buttons to adjust MC cartridge load impedance⓭ Display button to turn input and volume displays off

High-carbon cast ironinsulator feet
Headphone amplifier

Includes CD player
operation❸

Wood case withgrain mirror finish

Optional: AD-2900 phono equalizer unit
Adding the AD-2900 to the C-2900 allows you to play
analog discs.
■ Contains equalizer units with boards using glass cloth
fluorocarbon resin with totally separated left / right channels■ Ideal MC/MM independent input circuit to achieve highnoise performance■ Differential-style equalizer for high-precision RIAA characteristics■ Two input terminals to connect up to two tone arms
■ Functions that can be operated from the front panel■ Memory settings for each input terminal■ Robust aluminum case to shield against external noise■ MC Gain: 64 / 70 dB switching
Input impedance : 10 / 30 / 100 / 200 / 300 ohms switching■ MM Gain: 34 / 40 dB switching
Input impedance : 47 kilohms rated

Separate boards for left and right

Subsonicfilter

AD gain

MC/MMswitching

MC loadimpedance* Can be installed on earlier models (e.g. C-2850). Please contact yourAccuphase dealer or distributor.

Front Panel
Inputselector

Power switch

Input
display

Rear Panel

Remotesensor

Leveldisplay

Volumecontrol knob

Attenuator
buttonHeadphone jackOpen button* See the previous page for
information on the controls
in the sub panel.

Guaranteed Specifications
Frequency
response
Total harmonic
distortion

20 – 20,000 Hz ±0.2 dB

MM / 34 dB

20 – 20,000 Hz ±0.3 dB
All input
connectors

63 mV

Max. output level

Gain(Gain switching:18 dB)

LINE

252 mV

63 mV

20 kilohms

5.0 mV

1.26 mV

47 kilohms★AD: MM / 40 dB

2.5 mV

0.63 mV

47 kilohms★AD: MC / 64 dB

0.16 mV

0.04 mV

10 / 30 / 100 / 200 / 300 ohms

★AD: MC / 70 dB

0.08 mV

0.02 mV

Input connector

S/N ratio, Inputconverted noise

40 kilohms (20 kilohms / 20 kilohms)★AD: MM / 34 dB

10 / 30 / 100 / 200 / 300 ohms
2V50 ohms

252 mV

50 ohms

Input shorted (A weighting)
S/N ratio at rated output Input-converted noise

6.0 mV
3.0 mVBALANCED / LINE OUTPUT

600 ohms

RECORDER REC

10 kilohms–80 dB / 10 kHz
INPUTOUTPUT

Gain

BALANCED / LINE

BALANCED / LINE

18 dB
0 dB
52 / 58 dB

Loudness
compensation
6XEVRQLF¿OWHU
Headphone jack

110 dB★AD: MM / 34 dB

91 dB–137 dBV

85 dB

Attenuator★AD: MM / 40 dB

85 dB–137 dBV

85 dB★AD: MC / 64 dB

79 dB–155 dBV

85 dB

Powerrequirements★AD: MC / 70 dB

73 dB–155 dBV

85 dB
6.0 V

95 mV

★AD MC / 64 dB INPUTRECORDER REC–125 dBV(Distortion: 0.005 %, 1 kHz) RECORDER REC (at AD input)★AD MM / 40 dB INPUTBALANCED / LINE

113 dB

7.0 V(Distortion: 0.005 %,1 kHz)

190 mVBALANCED / LINE

S/N ratio (EIA)BALANCED / LINE OUTPUT

6.0 V★AD MM / 34 dB INPUT* ±6 dB GAIN
★AD MM: 34 / 40 dB
switching possible ★AD MM: 34 / 40 dB
for all modes except★AD MC: 64 / 70 dB
REC OUTPUT★AD MC: 64 / 70 dB

BALANCED / LINE

Supplied accessories● AC power cord
● Audio cable with plugs ASL-10B, 1 m (39.4")

External preamplifier
input connectors (Balanced)★AD MC / 70 dB INPUT

Crosstalk

252 mVBALANCED / LINE OUTPUT
Rated output voltage,
Output impedance ★RECORDER REC (at AD input)

Max. input
voltage

Input impedance

At rated output For 0.5 V output

AC power supplyconnector

BALANCED / LINE INPUT

Minimum load
impedance

BALANCED

External
preamplifier input
connectors LINE

Balanced output
connectors BAL 1, 2

Balanced input connectors
BAL CD / BAL

0.005%

Input sensitivity

Input connector

Input sensitivity,
Input impedance

20 – 20,000 Hz +0 –0.2 dB

At ratedoutput

Line outputconnectors
LINE 1, 2[Guaranteed specifications are measured according to EIA standard RS-490.]

MM / 40 dB, MC

20 – 20,000 Hz

Recorderconnectors
PLAY / REC

Phono equalizer
unit expansion slot

3 – 200,000 Hz +0 –3.0 dB

BALANCED / LINE INPUT★AD INPUT

Line input connectors
TUNER / CD /LINE 1, 2, 3

RECORDER REC

34 / 40 dB

BALANCED / LINE

82 / 88 dB

RECORDER REC

64 / 70 dB

1: +2 dB (100 Hz), 2: +4 dB (100 Hz), 3: +6.5 dB (100 Hz)
10 Hz–18 dB/octave

Suitable impedance

8 ohms or higher

Output level

2 V (40 ohms)

Level switching

LOW:-10dB, HIGH:+10dB from standard MID level–20 dB

120 V, 220 V, 230 V AC
(voltage as indicated on rear panel)

50 / 60 Hz

Power consumption

31 W [With AD-2900 expansion: 35 W]

Maximum
dimensions

Width 477 mm (18.78") × Height 156 mm (6.14") × Depth 412 mm (16.22")[With AD-2900 expansion: Depth 414 mm (16.23")]

MassNet24.2 kg (53.4 lbs) [With AD-2900 expansion: 25.1 kg (55.3 lbs)]

In shipping carton

31 kg (69 lbs)

★ With the AD-2900 expansion unit.

● Remote Commander RC-250● Cleaning clothRemarks★ This product is available in versions for 120/220/230 V AC. Make sure that the voltage shown on the rear panel matches the AC line voltage in your area.
★ The 230 V version has an Eco Mode that switches power off after 120 minutes of inactivity.
★ The shape of the plug of the supplied AC power cord depends on the voltage rating and destination country.

●The specifications and appearance of this product are subject to change without notice.

https://www.accuphase.com/

K2105Y

850-2225-10（B1）

PRINTED IN JAPAN