Accuphase T-1100 User manual

$$3&-34%2%/45.%2
●  Double-tuned front end easily handles high signal levels
●
 Revolutionary DDS principle for local oscillator ●Variable bandwidth
IF filter prevents interference ● Multipath reduction function ● Digital
FM detector keeps distortion and noise to a minimum ● DS-DC
achieves ideal stereo demodulation with DSP technology ●MDS plus
type D/A converter ●20-station memories also store function settings

Sine Wave
Data
Quartz
Oscillator
D/A
Converter
Output
Frequency
Divider
0110
Demodulated output
Phase Detector
FM Wave Signal
Input
Imaginary
Part
Real
Part
Division
Differentiation
tanθ
（tan1）
Phase
Angle(θ)
Arctangent
f0
Noise or adjacent
broadcast station
Narrow IF bandwidth
reduces interference
Wide IF bandwidth
is susceptible to
degradation by
noise and interference
DDS Local Oscillator
Attenuator
Local/Distance
Selector
Double
Balanced
Mixer
Double
Balanced
Mixer IF output
FM Antenna
Double-Tuned Circuit
RF
Amplifier Double-Tuned Circuit
AGC
Direct
Wave
Transmitter
Reflected
Wave
■Front End Circuit Diagram
■DDS Block Diagram
■Digital FM Demodulator
Coils used in double-tuned circuits
■IF bandwidth switchable in 6 stages
■FM Propagation Characteristics
The range of available program sources is getting
ever more varied: Compact Discs, analog records,
and net based music distribution, to name but a
few. But the FM tuner still has a special role to
play, since broadcasts cover the entire spectrum
from live performances of time-honored classical
works to the latest hits. The FM band provides a
rich choice of music all day long. In addition,
many local stations have recently come onto
stage using the live broadcast medium to best
advantage.
The T-1100 is a successor model to the highly
praised T-1000. Thanks to a blend of latest RF
circuit design with sophisticated digital signal
processing implemented by a high-speed, high-
precision DSP chip, it has become possible to
move most major functions of the tuner into the
digital domain without sacrificing performance or
sound quality. Audiophiles and music lovers can
now enjoy FM stereo at its best.
The newly developed front end features a double-
tuned circuit that optimizes sensitivity and
selectivity, as well as the revolutionary DDS
(Direct Digital Synthesis) principle for the local
oscillator. All functions after the intermediate
frequency (IF) stage are implemented using digital
signal processing in completely new and
innovative ways. This comprises the variable
bandwidth IF filter, multipath reduction function,
digital FM detector and DS-DC stereo
demodulator. The result is an FM tuner unlike any
other, offering further enhanced performance and
sound quality. Other attractive features include a
20-station memory, a coaxial output for digital
signal connection, two sets of line and balanced
analog outputs, and a supplied Remote
Commander for operation convenience. In sum,
this is a lavishly designed FM tuner that will meet
and surpass even the highest expectations.
The FM demodulator circuit is a crucial component that has a
significant effect on distortion and noise characteristics of the tuner’s
audio output. In the T-1100, the imaginary part of the digitized FM
signal is divided by the real part to extract the tangent of the phase
angle (
θ) . By calculating the arctangent from this, the phase angle
can be determined. Differentiation is then used to obtain the time
variation resulting in the FM demodulated output (audio output).
Ideal Digital FM Demodulation Principle
Variable Bandwidth IF Filter Improves Interference Performance
Multipath Reduction Function (MPR) Minimizes Reflections
DDS（Direct Digital Synthesis）
The signal from the antenna input is routed to an RF amplifier
and then mixed with the signal from a local oscillator for
conversion into the intermediate frequency (IF). The local
oscillator here is a highly advanced DDS (Direct Digital
Synthesis) circuit.
●The output of a quartz oscillator is supplied to the frequency
divider to create the timing (namely the sampling frequency)
with which the sine wave data are read out.
●Using this sampling frequency, the sine wave data are read
in the D/A converter to create the analog waveform output.
●Because there is no feedback loop, the frequency purity of
the D/A converter output can be kept identical to that of the
quartz oscillator.
■Anattenuatorintheinputstageenablesthetunertooperateatitsoptimum
pointalsowheninputlevelsareextremelyhigh,suchasinthevicinityofa
broadcasttowerorwhenusingacablenetwork.
■Two-stagedouble-tunedfrontendeliminatesintermodulationdistortionwith
strongsignals.
■Dual-gateMOS-FETsintheRFamplifierstageensureexcellentthird-order
intermodulationcharacteristics.
■Two-stage double-balanced mixer suppresses undesired signal compo-
nents.
■RevolutionaryDDSlocaloscillatorachievesamazingS/Nratio.
The IF BANDWIDTH selector of the T-1100 provides a choice of six settings
(50, 75, 100, 150, 250, 500 kHz). Normally, a wider bandwidth setting is pref-
erable in terms of perform-
ance characteristics, but
by restricting the band-
width, noise can be re-
duced in certain situations,
making it easier to obtain
a good quality signal from
a station affected by inter-
ference from a strong ad-
jacent station.
The variable bandwidth IF
filter is implemented using
a FIR (Finite Impulse Re-
sponse) type digital filter
with perfectly linear phase
characteristics, thereby
eliminating the phase shift
that can occur with con-
ventional IF bandwidth fil-
ters.
Double-Tuned Front End Eliminates Problems With High Input Signal Levels
4HE ULTIMATE &- STEREO TUNER ,ATEST 2& TECHNOLOGY AND ADVANCED
DIGITAL PROCESSING TECHNIQUES COME TOGETHER ON THE HIGHEST PLANE !LL
FUNCTIONS AFTER THE INTERMEDIATE FREQUENCY )& STAGE ARE PERFORMED BY
$30 SOFTWARE INCLUDING THE VARIABLE BANDWIDTH )& FILTER MULTIPATH
REDUCTION -02 FUNCTION DIGITAL &- DETECTOR AND $3$# STEREO
DEMODULATOR0ULSETUNINGPRINCIPLEALLOWSMANUALTUNINGANDSTATION
MEMORYTUNING$IGITALOUTPUTINCREASESCONNECTIONOPTIONS
Multipath reception refers to a condition where the same broadcast signal
reaches the antenna via several different propagation routes. In the case of
FM, this occurs when the signal travels to the antenna in a straight line, but
is also reflected and therefore slightly delayed by buildings, mountains or
other tall obstructions.
When the direct waves and
reflected waves are re-
ceived together, distortion
and noise occur.
The high-speed, high-
precision DSP chip in the
T-1100 makes it possible
to perform multipath reduc-
tion (MPR) through signal
processing that effectively
suppresses the harmful re-
flected components. This
technique which is based
on adaptive filtering princi-
ples ensures that only the
desirable direct wave com-
ponents are received, re-
sulting in high-quality audio
output.
■IF bandwidth is selected by turning knob
(with LED indication)

ResponseindB
FrequencyinHz
Stereo Separation
#HANNEL
3EPARATOR
#ROSSTALK
$OUBLE#ANCELLATION
Pilot Tone
Stereo-Modulated
Signal
#ROSSTALK
#ANCELLATION
（STSTAGE）
,
2
#ROSSTALK
#ANCELLATION
（NDSTAGE）
0ILOT4ONE
$IRECT
3YNTHESIS
20 30 50 100 200 500 1k 2k3k 5k 10k
0
− 10
− 20
− 30
− 40
− 50
− 60
− 70
− 80
− 5
− 15
− 25
− 35
− 45
− 55
− 65
− 75
Lch→Rch
Rch→Lch
Stereo Separation Characteristics
■DS-DC Type Stereo Demodulator Circuit
■Intermediate frequency (IF) signal from
front end is digitized by high-precision
A/D converter
■Functions after intermediate frequency (IF) stage (variable
bandwidth IF filter, multipath reduction, digital FM
detector, DS-DC stereo demodulator) are performed
through fully digital signal processing by a high-speed,
high-accuracy DSP chip, providing drastically improved
performance. The end result is an FM tuner of the highest
order.
■Supplied Remote Commander RC-410
Provides access to all functions of the tuner
(except power switching), as well as
(Accuphase) amplifier volume control.
●
DS-DC (Direct Synthesis − Double Cancellation)
/Pilot Tone Direct Synthesis
A conventional FM tuner uses a PLL circuit to extract the pilot tone and obtain the
frequency and phase components from the input signal (stereo-modulated signal). If the
level of the pilot tone decreases, noise will be heard and stereo separation becomes
extremely poor.
With DS-DC, the waveform of the pilot tone in the input signal is identified as is* and
generated directly by the DSP arithmetic. Therefore the pilot tone can be extracted
reliably even when a high level of noise is present. Impressive stereo separation can be
achieved even when the pilot tone level is low.
※Simply analyzing the signal and determining similarities.
4Crosstalk Double Cancellation
After the input signal has been separated into the left and right components, the circuit
eliminates crosstalk using a dual approach that also takes phase components into
consideration. The result is extremely thorough left/right separation.
DS-DC principle with DSP ensures ideal stereo
demodulation for amazing channel separation
The stereo demodulator in the T-1100 features
another Accuphase innovation called DS-DC (Direct
Synthesis
− Double Cancellation). The demodulator
comprises the two technologies described below.
Since all operations are carried out through software-
based algorithms in Digital Signal Processor, ideal
demodulation performance can be achieved, result-
ing in previously unheard-of channel separation.

■
Supplied accessories:
Notes
●
An FM antenna is required to use the T-1100. Please consult your dealer regarding antenna installation.
●
In residences with shared antenna systems, confirm that the antenna outlet carries FM signals.
●
Use a 75-ohm coaxial cable with F type plug for the antenna connection.
●The specifications and appearance of this product are subject to change without notice.
I1005Y PRINTED IN JAPAN 851-0194-00（B1）
Interferencesignal
400kHz
300kHz
200kHz
Selectivity
70dB
30dB
10dB
  *2 -
 

(
 

(

/4 ) 60
(
1
Pulse tuning system
Digital output connector
Signal strength indication Multipath level indication
Multipath reduction
(MPR) ON
SIGNAL indicator lit MULTIPATH/MPR indicators litMULTIPATH indicator lit
Attenuator function
Meter function selection and
MPR ON/OFF switching
MODE button
2 stations can be
programmed
in each button
■Front panel
■Rear panel
●
A C power cord
●Audio cable with plugs (1 m)
●Remote Commander RC-410
/LED indicators
METERMPRIF BAND WIDTH
4Meter (Signal strength/Multipath)
)Station number readout
0Reception frequency readout
(
1LED indicators
MUTE MODELOCALDISTANCE
6Tuning knob
2Power switch
* Meter function button SIGNAL/MULTIPATH
- Multipath reduction (MPR) ON/OFF button
IF bandwidth selector knob
Muting circuit ON/OFF button
Mode selector button
STEREO/BLEND/MONO
LOCAL/DISTANCE selector button
Stereo reception indicator
Memory set button
Station buttons (20 stations)
Antenna input connector (F type)
(
Phase selector for balanced output
 Analog output connectors BALANCED LINE
Digital output connector COAXIAL
 AC power connector (for supplied power cord)(
Monophonic
●Sensitivity Usablesensitivity   11dBf
S/N50dBquietingsensitivity 17dBf
●S/N ratio (80 dBf input, A-weighted) 90dB
●Total harmonic distortion
(80 dBf input, ±75 kHz deviation)
 20Hz 0.02％
 1kHz 0.02％
 10kHz 0.02％
●
Intermodulation distortion
(80 dBf input, ±75 kHz deviation) 0.01 ％
●Frequency response 10
− 15,000Hz ＋0 − 2.0dB
●Capture ratio
 1.5dB
●RF intermodulation 80dB
●Spurious response rejection 120dB
●Image rejection 100dB
●Alternate channel selectivity
●AM suppression (65 dBf input) 80dB
●Output voltage (±75kHzdeviation)  1.0V
Stereo
●Sensitivity S/N 40 dB quieting sensitivity 29 dBf
S/N 50 dB quieting sensitivity 37 dBf
●S/N ratio (80 dBf input, A-weighted) 85 dB
●
 Total harmonic distortion (80 dBf input, ±75 kHz deviation)
20 Hz 0.04 ％
1 kHz 0.04 ％
10 kHz 0.04 ％
●
 Intermodulation distortion (80 dBf input, ± 75 kHz deviation)
0.03 %
●Frequency response 10
− 15,000 Hz ＋0 − 2.0 dB
●Stereo separation100 Hz 60 dB
1 kHz 60 dB
10 kHz 50 dB
●Stereo trigger level 21 dBf
●Subcarrier suppression ratio70 dB
General
●Antenna input 75-ohm coaxial (F type connector)
●Standing wave ratio 1.5
●Tuning principleDDS synthesizer tuning
20-station random memory tuning
● FM detection principle  Digital FM demodulation principle
●Stereo demodulation principle DS-DC
●Digital output (IEC60958)
COAXIAL：0.5 VP-P 75 ohms
Sampling frequency：48 kHz/24 bits
●Output impedance
 BALANCED (XLR type connector)： 100 ohms（50 ohms/50 ohms）
LINE (unbalanced)：50 ohms
●Meter
Signal strength/multipath switchable
●Power requirements AC 120 V/230 V, 50/60 Hz
(Voltage as indicated on rear panel)
●Power consumption 20 W
●
Maximum Dimensions
Width 465 mm (18-5/16")
Height 140 mm (5-1/2")
Depth 406 mm (16-0")
●Weight 13.0 kg (28.7 lbs) net
19.0 kg (41.9 lbs) in shipping
carton
T-1100 Guaranteed Specifications [Guaranteed specifications are measured according to EIA standard RS-490.]
(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 and destination country.
(The reception frequency range, number of display digits, and tuning frequency steps
differ in models for different countries. The antenna connector may also be an IEC
type or F type connector. Please verify that you have the correct model for your area.
Remarks
■Two sets of analog outputs: balanced and line
■Phase selector for balanced output
●In the factory default condition, the switch is set to
the left side (pin 3 positive).
●If the connected preamplifier or integrated amplifier
uses a “pin 2 positive” arrangement, change the
setting of the switch.
■20-station memory with all function set-
tings
■Accuphase original pulse tuning system
provides traditional manual tuning feel
■Confirmation beep when operating tuning
knob and function buttons
■High-quality digital output connector (coaxial)
■MUTE button allows turning muting ON or OFF
during tuning
■MODE button allows selection of desired
reception mode
:STEREO: Normal stereo reception
@BLEND: Left and right signals are
mixed, to reduce noise
particularly in the upper
frequency range
.MONO: Stereo broadcast
reception forced to
monophonic
■Attenuator function for reducing input
level
LOCAL: Attenuator ON
■Meter for monitoring signal status
Signal strength as well as multipath condition and effect of multipath
reduction (MPR) can be verified.
Versatile Array of Functions
Frequency range and tuning step width
Model for Europe 87.50 MHz - 108.00 MHz
(in 50-kHz steps)
Model for USA 87.5 MHz - 108.0 MHz
(in 100-kHz steps)