m Revolutionary “Balanced AAVA Volume Control” m Separate
high-efficiency toroidal power transformers for left and rightchannels m Selectable preamp gain m Fully modular construction withseparate left/right units for each amplifier stage m Logic-controlled relays
for shortest signal paths m Independent phase selection for each input
position m Printed circuit boards made from glass cloth fluorocarbon
resin m Elegant cabinet with natural persimmons wood finish

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Reference preamplifier for the next generation — Balanced AAVA features two
AAVA circuits driven in balanced mode, realizing fully balanced operation for all
signals from input to output. Total of 20 unit amplifiers for left and right channels,
using printed circuit boards made from glass cloth fluorocarbon resin. Dual-monoconstruction with separate high-efficiency toroidal transformers providing plenty ofreserves. Individual phase setting for each input position.
After its founding in 1972, the first product unveiledby Accuphase was the separate amplifier pair C-200/
P-300. Ever since then, the company has been
unwavering in its dedication to high-end audio, placingutmost emphasis on superior quality and truly faithfulsound reproduction. This has resulted in the creationof products sustained by peerless technology andproviding outstanding value to their owners. Each
product was recognized for genuine creativity and solid
reliability, with many models attaining legendary status.
Both in Japan and worldwide, audiophiles continue
to hold Accuphase in high esteem. The C-3800 now
concentrates the extensive know-how and expertise
gained over the years in the field of preamplifiers into a
product that is destined to become the new reference
for the next generation. Both in concept and circuit
execution, this preamplifier stands at the very forefrontof technology. Each and every part has been carefully
selected through extended cycles of listening tests.
Eschewing comprises in any respect, Accuphasehas created the ultimate in performance and soundquality.
Foremost among the distinguishing features of theC-3800 is the further evolved “Balanced AAVA”
concept. Two AAVA circuits are driven in a balanced
configuration, resulting in ideal volume control
behavior from balanced input to balanced output. The
complete path forRegular AAVA
all signals from theinput connectors Balanced input
Unbalanced
to the outputs isoutput
fully balanced,
ensuring utmost
Balanced AAVA
purity and further
improved electricalcharacteristics. TheBalanced output
result is reflected in Balanced input
notably improved
music reproductionthat takes fidelity to

the next higher plane.
Since making its debut in the C-2800 in 2002,
AAVA has revolutionized the concept of the analog
preamplifier. Each subsequent preamplifier andintegrated amplifier from Accuphase has featured
AAVA technology. Both AAVA and Balanced AAVA
are fundamentally different from the digital signal
processing approach involving A/D and D/A conversion.
The volume control operates purely in the analog
domain. Using AAVA to change the volume means thatthe high S/N ratio and low distortion of the amplifier
remain totally unaffected. Frequency response andsound quality do not suffer at any listening level.
There are no left/right tracking differences or crosstalk,and no other performance related degradations. The
conventional concept of volume control is well and truly
a thing of the past. Another benefit of AAVA is the factthat it consists entirely of highly reliable semiconductor
parts, so that performance and sound quality willremain undiminished for many years to come.

Balanced AAVA (Accuphase Analog Vari-gain Amplifier) Volume Control
AAVA is a radically different volume control principle that eliminates all variable resistors from the signal path. The C-3800 employs two AAVA modules
in a fully balanced configuration from input to output. This makes it possible to realize fully balanced signal paths throughout the preamplifier, extending
from the input connectors to the outputs.

n Powerful current feedback amplifier inAAVA input stage

The input stage employs four MCS+ current
feedback amplifiers in an instrumentation
amplifier configuration, featuring outstanding
high-speed, low-noise operation.

Conversion into current with
16 weighting stages (1/2 - 1/216)

16 current switches(65,536 possiblecombinations)

V-I Converter

Operation Principle of Balanced AAVA in C-3800

n 36 V-I converter amplifiers

Because Balanced AAVA adopts a completely
balanced current source configuration, 16
amplifiers each are used for the + input and input, with the V-I amplifiers for the upper twobits being paralleled, resulting in a total of 36
amplifiers. This ultra-low noise current source
contributes to further improved S/N ratio.

High Voltage
Current Feedback
Amplifier

I-V Converter

Current values
are added

n Volume control resolution

AAVA adjusts the listening volume by means of
16 weighted V-I converter amplifiers which arecontrolled by current switches. The number ofpossible volume steps set by the combinationof these converter amplifiers is 2 to the powerof 16 = 65,536.

n AAVA ensures high S/N ratio, lowdistortion, and uniform frequency
response and sound quality at anyvolume

Because AAVA does not introduce a change inimpedance, there is no deterioration of S/N ratio
at any practical volume setting, and frequency
response remains totally uniform. The soundis always perfectly transparent and the tonal
quality is not altered in any way.

Reconversion ofcurrent into voltage

Volume level display

INPUT

Balanced
Input

INPUT

OUTPUTCPU controls current on/off
switches so that volumelevel matches knob position• Volume• Balance• Attenuator

BalancedOutput

OUTPUTV-I Converter
Volume knob is turnedand volume level position
is detected

n No more left/right tracking differencesor crosstalk

I-V Converter

Because the channels can be kept separate,
there is virtually no left/right tracking error also
at very low volume levels, and crosstalk does
not present a problem.

n AAVA means analog processing

The AAVA circuit converts the music signal froma voltage into a current, alters gain by meansof current switches, and then reconverts thecurrent into a voltage. The entire process iscarried out in the analog domain.

n Amplifier display shows accurate gainn Attenuator and left/right balance
control also implemented by AAVA

Current values
are added

High Voltage
Current Feedback
AmplifierConversion into current with
16 weighting stages (1/2 - 1/216)

16 current switches(65,536 possiblecombinations)

Reconversion ofcurrent into voltage

The Ultimate Harmony

of Craft and Beauty

Positioned at the very pinnacle of analog preamplifier
technology, the C-3800 implements the latest circuit
topology using only the finest parts and materials. The
gold-hue front panel and natural persimmons wood cabinet
present a simple yet refined visual appearance that exudes
warmth and solid presence wrapped in timeless esthetics.

— Extruded from solid aluminum block —High-rigidity volume sensor construction
Turning the volume knob on the front panelcauses the actual volume level position to bedetected. The corresponding signal is sent
to a CPU which in turn controls the actionof the AAVA circuitry. The massive knob
provides a smooth operation feel and further
enhances position detection accuracy.

* Interior parts in the image are simulated.

■ Unit amplifier assemblyA total of 20 unit amplifiers handle the signaltransmission for the left and right channel. The
printed circuit boards are made from glass
cloth fluorocarbon resin, and the copper
foil surfaces are gold-plated. The unit
amplifiers are mounted on a glass epoxy
motherboard, and left and right sections
are kept completely separate. An 8 mm
thick frame made of hard aluminum
prevents mutual interference by
providing electrical shielding andsuppressing physical vibrations.

AAVA operation principle

The amplification circuitry of the C-3800 consists of various assemblies
for input buffer, AAVA circuitry, balanced output, headphone amplifieretc. (total of 20 unit amplifiers).

C-3800̲ENG̲1.indd 3

The music signal is converted into 16 types ofweighted current by V-I (voltage - current) converting
amplifiers [1/2, 1/22, ... 1/215, 1/216]. The 16 currents
are turned on or off by 16 current switches, and thecombination of switch settings determines the overall
volume. The switching operation is controlled by a
CPU to match the position of the volume control knob.
The combined current forms a variable gain circuitthat adjusts the volume of the music signal. The
respective currents are combined and converted backinto a voltage by an I-V (current - voltage) converter.

■ Supplied remotecommander RC-210
Allows volume adjustment,
input source switching,and other operations.

2010/06/08 9:52:25

n Logic-controlled relays assuren Selectable preamplifier gain withn Versatile arrangement of bal-n EXT PRE function allows use ofhigh sound quality and long-term
reliability.

three settings (12 dB, 18 dB,
24 dB)

anced and line input and output
connectors.

external preamplifier“EXT PRE” selectorn Output phase selectable individ-n Printed circuit boards in signal

ually for each input, with visualindication. When INV LED is lit,output phase is inverted. WhenLED is out, phase is normal.

Balanced input and output connectors

transmission circuitry made fromglass fluorocarbon resin with low
dielectric constant and low loss.

n Ideal power supply uses high-Gain selector

LED indicators Phase selector buttonn Dedicated headphone amplifier
with three selectable gain settings

efficiency toroidal transformers
and filtering capacitors selectedfor sound quality (10,000 μF × 12)
in fully monaural configuration.

n Massive cabinet with persimmons wood finish

Headphonelevel selectorn More versatile features:• Provisions for recording andplayback with a recorder• Attenuator (-20 dB)• Loudness compensator withthree selectable characteristics• Alphanumeric indication of
input position and volumelevelHigh-efficiency toroidal transformers

LOUDNESS COMPENSATOR : ON/OFF
Response in dB

Line input and output connectors

Filtering capacitors with high sound quality
Frequency in Hz

Loudness compensator characteristics

n Front PanelAC-3800 Guaranteed Specifications
BCDEFGB* Guaranteed specifications are measured according to EIA standard RS-490.
* Gain selector set to 18 dB positionm Frequency Response

BALANCED LINE INPUT
3 – 200,000 Hz +0, –3.0 dB
20 – 20,000 Hz +0, –0.2 dB

m Total Harmonic Distortion (for all inputs)

0.005%m Input Sensitivity, Input ImpedanceSensitivity
For rated output For 0.5 V outputInputHI

JKL M NP QO

Pressing this button
opens the sub paneln Rear PanelRST

BALANCED

252 mV63 mVLINE

252 mV63 mVInputimpedance
40 kΩ(20 kΩ/20 kΩ)
20 kΩ

m Rated Output Voltage, Output Impedance

BALANCED/LINE OUTPUT

2 V 50 ohms

m S/N Ratio

TInputBALANCED
LINE

Input shorted, IHF-A weighting
S/N ratio at rated output
113 dB
113 dBS/N ratio (EIA)
110 dB
110 dBm Maximum Output Level (0.005% THD, 20 – 20,000 Hz)

BALANCED/LINE OUTPUT
RECORDER REC (with BALANCED input):

7.0 V
6.0 V

m Maximum Input Level

BALANCED INPUT:
LINE INPUT:

8.0 V
6.0 V

m Minimum Load

BALANCED/LINE OUTPUT:
RECORDER REC:

600 ohms
10 kilohms

m Crosstalk–90 dB or above (10 kHz) (EIA)

Impedancem Gain (gain selector: 18 dB)

TT

T★

A Input selector (with LED indication)
N Recorder output ON/OFF and PLAY buttons
O Headphone level selector
LINE 3, LINE 2, LINE 1, BAL 2, BAL 1,
CD-BAL, CD, TUNER, LINE (AD), BAL (AD)
LOW, MID, HIGH
B Function LED indicator
P Headphone jack
C Alphanumeric input indicator
Q Attenuator button
D Gain selector
R Line (unbalanced) input connectors
12dB, 18dB, 24dB
LINE(AD), TUNER, CD, LINE 1,2,3E Loudness compensator selector
S Recorder playback/recording connectors
T Line (unbalanced) output connectors (2 sets)
OFF, 1, 2, 3
T Balanced output connectors (2 sets)
F Volume level indicator
G Volume control knob
With line input signal: pin b negative (-), pin c positive (+)
H Power switch
With balanced input signal: same phase as source equipment
I Output selector(Can be switched with phase selector button K).
T Balanced input connectors (4 sets)
EXT PRE, ALL, BAL, LINE, OFF
J Display ON/OFF switch
BAL (AD), CD-BAL, BAL 1, 2
K Phase selector button
T EXT PRE input connectors (2 sets) LINE/BAL
L Stereo/mono selector button
T AC power supply connector★

* Gain selector allows increase or decrease by 6 dB, except for REC output.
BALANCED INPUT→ BALANCED OUTPUT: 18 dB
BALANCED INPUT→ LINE OUTPUT:
18 dB
LINE INPUT→ BALANCED OUTPUT: 18 dB
LINE INPUT→ LINE OUTPUT:
18 dB
BALANCED/LINE INPUT → RECORDER REC:0 dB

m Loudness

1: +2 dB (100 Hz), 2: +4 dB (100 Hz), 3: +6.5 dB (100 Hz)

m Headphone Jack

Suitable impedance:8 ohms or above
Output Level:
2 V (40 ohms)
Gain (LOW, MID, HIGH): ±10 dB from standard MID levelm Attenuator–20 dBm Power Requirements

AC120 V/230 V, 50/60 Hz(Voltage as indicated on rear panel)m Power Consumption

55 watts

Compensationm Maximum Dimensions Width 477 mm (18-3/4”)

Height 156 mm (6-1/8”)
Depth 412 mm (16-1/48”)

m Mass24.8 kg (54.7 lbs) net
32.0 kg (70.5 lbs) in shipping carton

M Balance control
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 anddestination country.
m■ Supplied accessories: ● AC power cord
● Audio cables with plugs (1 m)● Remote commander RC-210● Cleaning cloth

Specifications and design subject to change without notice for improvements.

http://www.accuphase.com

C-3800̲ENG̲1.indd 2

F1010YPRINTED IN JAPAN

850-0192-00 (B1)

2010/06/08 9:52:21