Accuphase C-2420 User Manual

● AAVA volu me control for h igh performanc e and outstandi ng sound

● Separate power transformers for left and right channels ● Selectable preamp

gain ● Fully modular construction with separate left/right units for each amplifier
stage ● Logic-controlled relays for shortest signal paths ● Independent phase
selectio n for e ach input position ● Optional phono equalizer unit allows
playback of analog records ● Side panels with elegant natural wood finish

Further advanced AAVA volume control elevates performance to a new realm
— A preamplifier for the next generation, featuring AAVA technology
developed for the C-2820. Modular design of AAVA and other amplifier
sections realized in a dual-mono construction with separate power supplies.
Preamplifier overall gain selection setting and phase selection settings for each
input position stored in memory. Numeric indication of volume level. Optional
phono equalizer unit allows playback of analog records with ultimate fidelity.

The Precision Stereo Control Center C-2420 reflects
the refined sonic sensibility of Accuphase while incor­porating advanced technology features developed for
the C-3800 and C-2820. A full model change has fur­ther elevated performance and sound quality to new
heights.
Ever since being first introduced in the C-2800 pream­plifier in 2002, AAVA technology has been continually
refined and improved, while of course retaining the un­derlying principle. The AAVA volume control operates
fully in the analog domain, but it eliminates all potenti­ometers from the signal path. The advantages of this
approach are many: outstanding S/N ratio, extremely
low distortion, no change in frequency response and
sound quality at any listening level, no left/right level
differences or crosstalk, and no other performance re­lated degradations. The conventional concept of
volume control in analog preamplifiers is now well and
truly a thing of the past. Like the C-2820, the new
C-2420 features a high-rigidy, high-precision volume
sensor extruded from a solid aluminum block and
linked directly to the massive volume knob. Both ope­ration feel and accuracy of operation are significantly
improved by this design.
The C-2420 features separate power supplies for left
and right channel, each with a dedicated power trans­former, filtering capacitors and peripheral circuitry. Mod­ular units for the line input, balanced input, AAVA, and
other circuit stages are arranged separately for left and
right channels, to eliminate any risk of unwanted electri­cal or mechanical interaction between the two stereo
channels. A wide variety of versatile functions make the
C-2420 a true control center. There are tone controls
designed for optimum sonic performance, a loudness
compensator, subsonic filter, recorder related functions,
overall preamp gain selection, EXT PRE provision for
use of another preamplifier, individual phase selection
for each input position, and more.
The separately available Phono Equalizer Unit AD-2820
supports both MC and MM cartridges and allows the
reproduction of analog records with utmost fidelity.
Advanced technology enables performance and
sound quality on a level that approaches the realm of
top-of-the-line products. The C-2420 ushers in a new
era of preamplifier excellence.

■

Short and straight signal
paths, along with logic­controlled relays for sig­nal switching assure
high sound quality and
long-term reliability.

■ Versatile arrangement of

line and balanced input

Balanced input and output connectors

and output connectors.

■ EXT PRE function allows use of external preamplifier.

■ Selectable preamplifier gain with three settings (12 dB,

18 dB, 24 dB).

■ Output phase selectable individually for each input,

with visual indication. When INV LED is lit, output
phase is inverted. When LED is out, phase is normal.

■ Dedicated headphone amplifier ensures great sound and

features two selectable gain settings (standard, +10 dB)
for optimum matching to headphone efficiency.

■ Fully balanced input circuit shuts out external noise.

■ Side panels with beautiful natural wood finish.

■ Tone controls using summing active filters for optimum

sound quality.

■More versatile features:

●

Provisions for recording and playback with a recorder

●

Loudness compensator enhances low end presence

●

Attenuator (-20 dB)

●

Subsonic filter for removing ultra-low-frequency noise

●

Numeric indication of preamplifier overall gain and volume level

6

4

2

0

−

2

−

4

SUBSONICFILTER：ON

−

6

−

8

ResponseindB

−

10

−

12

−

14

−

16

−

18

1     10    100    1k    10k   100k    1M

FrequencyinHz

Frequency Response / Subsonic Filter Characteristics

18

16

14

12

10

ResponseindB

−

−

−

LOUDNESSCOMPENSATOR：ON

8

6

4

2

0

2

4

6

10        100       1k       10k       100k

Loudness Compensator Characteristics

FrequencyinHz

Line input and output connectors

LED indicators for
EXT PRE
function and
phase selector
button

INPUT

Principle of tone control circuitry

(summing active filter)

16

Low

frequency

12

range

8

Boost

4

0

−

4

ResponseindB

−

8

Cut

−

12

BASS TREBLE

adjustment range adjustment range

−

16

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Tone Control Characteristics

FrequencyinHz

Gain selector

High
frequency
range

OUTPUT

C-2420 Block Diagram

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