● AAVA volume control for high performance and outstanding sound ● Separate powertransformers for left and right channels ● Selectable preamp gain ● Fully modular construction
with individual left/right amplifier units on motherboard ● Logic-controlled relays for shortest
signal paths ● Independent phase selection for each input position ● Optional phono equalizer
unit enables playback of analog records ● Elegant side panels with natural wood grain finish

Featuring highly sophisticated AAVA volume control technology
Next-generation preamplifier takes C-2850 technology to another plane.
Blending the purely analog AAVA volume control circuit with sophisticated technology inherited from the C-2850
results in superb S/N ratio and a refinement of expression that brings new clarity to the music. The utterly smooth
operation feel of the volume sensor assembly and a top plate made of brushed aluminum with a hairline finish
demonstrate a level of dedication and hands-on craftsmanship that pervades every aspect of this preamplifier. EachC-2450 is individually honed to provide nothing short of perfection. Experience music as it was meant to be heard.

Innovative: At the leading edge of technology■ AAVA operation principle is purely analog
The AAVA circuit converts the input music signal into 16 types ofweighted currents which are then combined according to the positionof the volume control knob. The combination of signal currents forms
a variable gain circuit that adjusts the level of the music signal.

How AAVA works
OutputOutput of 16 V-I converters is
combined for volume control
action

0.5

0.4

0.3

Current ratio

0.2

0.1

0

16 types ofV-I converters

22223324425526

6Music signal isconverted into16 types of weightedcurrents■ Supplied RemoteCommander RC-220
Allows volume adjustment
and input source switching.

Sound quality: Simply aiming for the best

■ Separate left/right power supplies
The power supply circuitry not only acts as the energy source of an amplifier, thecurrent that it supplies to the load also has a significant influence on sound quality.
The C-2450 incorporates four custom-made filtering capacitors which are rated for
10,000 μF and have been specially tuned for optimum sonic properties. Along withthe power transformer, the entire power supply section is duplicated and kept
separate for the left and right channel, resulting in a full mono construction. Theentire circuitry from the input right through to the output benefits from a strong andstable supply of current which enhances the quality of the musical signal.

21Input■ Separate unit amplifiers for left and right
The main amplification tasks such as input buffering, AAVA, balanced output,and headphone output are handled by a total of six modular amplifiers for eachchannel. These unit amplifiers are mounted on a glass epoxy motherboard, withleft and right sections being kept completely separate. In order to eliminate
unwanted mutual interference between the amplifiers, a sturdy frame is used toprovide support. As a result, both electrical interference and physical vibrations
are reliably suppressed, creating an ideal operation environment.

V-I converters enablefinely graded control
1－
1－
1－
1－
1－
1－
1－
1－
1－
1－
1－
1－
1－
1－
1－
1－

■ High-accuracy, high-rigidity volume sensor assembly withresponsive yet solid feel
Although AAVA adjusts the volume level by combining the output ofweighted amplifiers, it is operated using a volume knob that appears similar
to conventional systems. Internally however there are major differences.
The volume sensor mechanism that detects the angular position of thevolume knob rests on a frame extruded from a massive aluminum block andfinished with utmost precision. The volume knob feels both responsive andsolid when rotated and ensures extremely accurate position detection. The
entire mechanism is supported on the chassis by a floating suspension
using insulators, which has the added advantage of extremely quiet
motor-driven operation when the remote commander is used.

Sturdy frame construction
with separate left/right layout

2772882992

1010211

11212

12213

1321414215

15216
16

Minimum value for control
current: 1/65,536

Advanced Features

Balanced input and output connectors

2134

5678

■

91 Output selector

6 Headphone level selector button

2 Subsonic filter button for effectively removing ultra low
frequency noise without affecting sound quality

7 Gain selector

3 AD gain selector for choosing equalizer gain

9 Output phase selector button

4 MC/MM button for selecting phono cartridge type101001k
10kFrequency in Hz

100k1M

Level display on/off button

Boost1612Low frequency
range

40−4−8−121001kFrequency in Hz

10k

100kLoudness compensator characteristics

High frequency
range

8Response in dB

LOUDNESS COMPENSATOR：ONCutSUBSONIC FILTER：ON

1181614121086420−2−4−610Response in dB

6420−2−4−6−8−10−12−14−16−188 Recorder selector for recording or playback
Mono/stereo selector button for combining left/rightchannel signals

5 MC load impedance button for selecting load
impedance when using MC cartridge

Frequency response/subsonic filter characteristics

Top plateLine input and output connectors[Sub panel]

Response in dB■ Logic-controlled relays for signal switching assurehigh sound quality and long-term reliability■ Total of 10 inputs and 5 outputs
Thanks to a versatile complement of input andoutputs, the C-2450 is ready for any programsource combination.
■ EXT PRE function allows use of external
preamplifier
Setting the OUTPUT selector to the EXT PRE
position allows the use of an external preamplifier
or other component without having to changesystem connections.
■ Selectable preamp gain
Overall gain can be set to 12 dB, 18 dB, or 24 dB.
■ Eliminate phase differences in balanced
connections
The PHASE button makes it easy to compensate
for differences in absolute phase of any input or
output component connected via a balanced link.
■ Independent phase selection for each input position
The phase can be set and memorized separately
for each input and recorder selector position.
■ On/off switching capability for level display■ Subsonic filter removes ultra low frequency noise■ Loudness compensator function offsets thecharacteristics of human hearing■ Tone controls using summing active filters for
optimum sound quality■ Dedicated headphone amplifier optimized forsound quality■ Elegant side panels with natural wood grain finish■ Thick aluminum top plate with exquisite
hairline finish−1610BASS
adjustment range

TREBLE
adjustment range

10010k1kFrequency in Hz

Tone control characteristics

100k

Option: Dedicated add-on

Phono Equalizer Unit
Analog records can be reproduced by installing the dedicated phonoequalizer unit AD-2850 in a rear-panel slot.
The AD-2850 features separate input circuitry for MC and MM cartridges to ensure optimum matching and realize outstanding S/N ratio. The
built-in differential RIAA equalizer circuit is designed to provide superaccurate RIAA equalization characteristics. The printed circuit boards
are made from glass cloth fluorocarbon resin and housed in a sturdy
aluminum enclosure to minimize any kind of external influence.
■ MC

Gain:
60/70 dB, switchable
Input impedance: 10/30/100/300 ohms, switchable

■ MM

Gain:
30/40 dB, switchable
Input impedance: 47 kilohms■ Function setting controls on C-2450 front panel
AD-2850 installation

Phono equalizer with separate mono construction for left and right channel

Buttons for subsonic filter, AD gain, MC/MM selection, MC load impedance

Front Panel

Rear Panel

MC/MM selector button

AD gain selector button
Subsonic filter button

RECORDER connectors

Function display

Volume control

Headphonejack
Attenuator
buttonLoudness
compensator button
Button for opening thesub panel
Recorder selector
Gain selector
Balance control
Level display
Level display on/off button

Power switch
Opening sub panel

Output selector
BASS/TREBLE controls
Tone control on/off button
Output phase selector
Mono/stereo selector button
Headphone level selector buttonLine output connectors

REC / PLAY

MC load impedance selector button

Input selector＊For information regarding use in other preamplifiermodels (C-2850, C-2420 etc.), or regarding compatibility with previous phono equalizer units (AD-2820 etc.),
please contact your Accuphase dealer or distributor.

LINE 1, 2External preamplifier input
connectors (Line)

Line input connectors
AD-2850
installation slot TUNER / CD / LINE 1, 2, 3

Balanced input connectors

EXT PRE INPUTS (LINE)

External preamplifier
input connectors(Balanced)

CD-BAL / BAL

Balanced output connectors

EXT PRE INPUTS (BAL)

With line input signal: Pin ② ー Pin ③ ＋With balanced input signal: Same phase as input
source component (Can be changed with phaseselector button on front panel)

AC power supply ★
connector

BAL 1, 2

Guaranteed Specifications＊Guaranteed specifications are measured according to EIA standard RS-490. AD: Analog Disc ＊Specifications with AD-2850 installed. ＊Gain selector set to 18 dB position.

3 - 200,000 Hz ＋0 －3.0 dB
20 - 20,000 Hz ＋0 －0.2 dB
AD INPUT: [MM/40dB, MC]: 20 - 20,000 Hz ±0.2 dB
AD INPUT: [MM/30dB]:
20 - 20,000 Hz ±0.3 dB

Frequency Response BALANCED/LINE INPUT:

Total Harmonic Distortion (for all inputs)
Input Sensitivity,
Input Impedance

Input0.005%
Input Sensitivity

For rated output

AD: MM/30 dB INPUT
AD: MM/40 dB INPUT
AD: MC/60 dB INPUT
AD: MC/70 dB INPUTBALANCED/LINE

8.0 mV
2.5 mV
0.25 mV
0.08 mV
252 mVFor 0.5 V outputInputimpedance
47 kilohms
47 kilohms

2.0 mV
0.63 mV
0.063 mV 10/30/100/300 ohms, switchable
0.02 mV 10/30/100/300 ohms, switchable
63 mV 40 kilohms/20 kilohms

Rated Output Voltage, BALANCED/LINE OUTPUT:
2 V 50 ohms
Output Impedance RECORDER REC (with AD input): 252 mV 200 ohms
S/N Ratio,
Input-converted Noise

Input shorted (A weighting)
S/N ratio at rated output
94 dB
AD: MM/30 dB INPUT
84 dB
AD: MM/40 dB INPUT
80 dB
AD: MC/60 dB INPUT
72 dB
AD: MC/70 dB INPUT
110 dBBALANCED/LINEInput

EIA S/N
85 dB
85 dB
85 dB
85 dB
108 dB

Maximum Output Level BALANCED / LINE OUTPUT:
7.0 V
RECORDER REC (with AD input): 6.0 V■ Supplied accessories● Power cord
● Audio cables with plugs (AL-10)● Remote commander RC-220● Cleaning cloth

Maximum LINE Input Voltage BALANCED /LINE INPUT: 6.0V
Maximum AD Input Voltage MM [30/40 dB] INPUT:
310/96.5 mV(1 kHz, 0.005% THD)MC [60/70 dB] INPUT:
9.5/3.2 mV
Minimum Load Impedance BALANCED/LINE OUTPUT: 600 ohms
RECORDER REC:10 kilohmsGain
BALANCED INPUT→ BALANCED OUTPUT:
18 dB(18 dB position)
BALANCED INPUT→ LINE OUTPUT:
18 dB→ BALANCED OUTPUT:
18 dB
Gain selector switch: LINE INPUT
LINE INPUT→ LINE OUTPUT:
18 dB
12/18/24 dB
BALANCED/LINE INPUT → RECORDER REC:0 dBswitchable
AD [MM: 30/40 dB] INPUT → BALANCED/LINE OUTPUT: 48/58 dB
AD [MM: 30/40 dB] INPUT → REC OUTPUT:
30/40 dB
AD [MC: 60/70 dB] INPUT → BALANCED/LINE OUTPUT: 78/88 dB
AD [MC: 60/70 dB] INPUT → REC OUTPUT:60/70 dB
Tone Controls
Turnover frequency and adjustment range
Bass: 300 Hz ±10 dB (50 Hz)
Treble: 3 kHz ±10 dB (20 kHz)
Loudness Compensation ＋6 dB (100 Hz)
Headphone Jack
Output level: 2 V (40 ohms), Suitable impedance: 8 ohms or above
Subsonic Filter
10 Hz: －18 dB/octave
Attenuator－20 dB
Power Requirements 120 V/220 V/230 V AC, 50/60 Hz (Voltage as indicated on rear panel)Power Consumption 38 W
Maximum Dimensions Width 465 mm (18.3")
Height 150 mm (05.9")
Depth 409 mm (16.1")(Depth 414 mm (16.3”) with AD-2850 installed)
Mass

19.0 kg (41.9 lbs), 19.9 kg (43.9 lbs) with AD-2850 installed
25.0 kg (55.1 lbs) in shipping carton

Remarks★ 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 AC inlet and plug of the supplied power cord depends on the voltage rating and destination country.

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

5年間保証

G1705Y PRINTED IN JAPAN 850-2205-00（B1）