Accuphase T-1100 Gebruikershandleiding - Pagina 3
Blader online of download pdf Gebruikershandleiding voor {categorie_naam} Accuphase T-1100. Accuphase T-1100 4 pagina's. Dds fm stereo tuner
Pagina afdrukken■ 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 b y a h i g h - s p e e d ,
h i g h - a c c u r a c y D S P c h i p , p r o v i d i n g d r a s t i c a l l y i m p r o v e d
performance. The end result is an FM tuner of the highest
order.
●
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.
Crosstalk 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 (Direct Synthesis − Double Cancellation)
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.
※Simply analyzing the signal and determining similarities.
■ Supplied Remote Commander RC-410
Provides access to all functions of the tuner
(except power switching), as well as
(Accuphase) amplifier volume control.
Stereo-Modulated
Signal
Pilot Tone
■ DS-DC Type Stereo Demodulator Circuit
Stereo Separation
0
−5
−10
−15
−20
−25
−30
−35
−40
−45
−50
−55
−60
−65
Lch→Rch
−70
Rch→Lch
−75
−80
20 30 50 100 200 500 1k 2k
3k 5k
Frequency in Hz
Stereo Separation Characteristics
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10k