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In digital audio, music is processed in digital form. The music played by musicians in a 
recording studio or a concert hall is picked up by a microphone and recorded in digital form, 
to be released for sale as packaged media, including CD. The consumers buy the CD to play 
on a CD player: the recorded music is converted from digital to analog for playback through 
an amplifier and speakers. The process of playing digital music involves analog/digital 
conversion and digital/analog conversion as shown below.

Process of Playing Digital Music

The sound quality of a signal depends on the following two factors when the signal 
is converted from analog to digital.

• Quantization wordlength (bits), which determines resolution or the expression of 
music in the amplitude domain.

• Sampling frequency, which determines the frequency response or the expression 
of music in the frequency domain.

CC Converter

CC Converter

Problems with Digital Conversion

Problems with Digital Conversion

RX-D702

Summary of Contents for RX-D702

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Page 2: ...e cinema is not only the stylish design Despite the slim dimensions the units are ready to deliver powerful high quality sound from various sources including PC music files and provide superior picture quality too What s more their expanded connectivity lets you easily connect the units with your PC and even permits HDMI connections the latest interface for transmitting audio video signals Enablin...

Page 3: ... Receiving Uncompressed PCM Data from PC 2 CC Converter A JVC Original Technology for Superior Sound 3 Aureus High Performance DSP for Superior Sound Quality 4 Design Concepts Design Concepts Hybrid Feedback Digital Amplifier Ver III An Upgraded Version of JVC Trademark Digital Amp for Unmatched Sound Quality 5 ...

Page 4: ...X D702 Connection Example RX D702 Effect Examples 1 10 07 06 05 Effect Examples 2 11 The JVC A V receivers deliver not only superior sound but also superb pictures with a host of advanced technologies The units feature HDMI terminals and use of DCDi by FAROUDJA Connection Example RX D402 RX D401 Connection Example RX D402 RX D401 08 What is DCDi by FAROUDJA What is DCDi by FAROUDJA 09 ...

Page 5: ...gh Definition Multimedia Interface An Industry Supported Digital Audio Video Interface Developed for Next Generation Home AV Devices Its remarkable benefits include 1 All digital provides the highest quality available HDMI is the only interface in the industry that can handle both uncompressed high definition video and uncompressed multi channel audio Supported HD video formats include 720p 1080i ...

Page 6: ...Display Display Digital Digital A D A D Converter Converter Receiver All Digital Transmission of High Quality Video Audio Even System Control is available 3 HDMI Cables DVD Player STB Receiver Display 10 Audio 9 Video Cables Receiver Display 5 1 ch Audio 2 ch Audio Component Video DVD Player STB Single Cable Connections RX D702 RX D402 Also applies to RX D401 ...

Page 7: ... TX TX RX RX S Video Composite 480p HD 480p 480i p Y Pb Pr Speakers 480i p 720p 1080i 480i p 720p 1080i PCM DVD Audio DD DTS DVD VDR D VHS STB DVD Audio SPDIF Component Component HDMI HDMI S Video S Video Composite Composite Inputs Outputs Connection Example RX D702 Connection Example RX D702 RX D702 Hybrid Feedback Hybrid Feedback Digital Amplifier Digital Amplifier ...

Page 8: ...TS DVD VDR D VHS STB DVD Audio SPDIF S Video Composite Connection Example RX D402 D401 Connection Example RX D402 D401 RX D402 DSP DSP Speakers Hybrid Feedback Hybrid Feedback Digital Amplifier Digital Amplifier Component Component HDMI HDMI S Video S Video Composite Composite Inputs Outputs I P I P Conversion Conversion A D A D Converter Converter Also applies to RX D401 ...

Page 9: ...roduction of high definition pictures including Film Mode Recreates the original film frames by accurately blending the fields back together in progressive scanning for images free of motion artifacts and with full vertical resolution 3D Cross Color Suppression 3D Noise Reduction Fleshtone Adaptive Noise Reduction RX D702 RX D402 Video Mode Delivers pictures from video sources by eliminating jagge...

Page 10: ...eliminating staircasing or jagged edge artifacts Smooth Diagonal Edges Jagged Edges on Diagonal Lines Smooth diagonal lines are also delivered by the 3D Deinterlacer Cross Color Suppression While composite signals are decoded high frequency luma information leaks into the chroma channel generating noise that looks like flashing colors or rainbow patterns The Cross Color Suppression effectively eli...

Page 11: ...ect unnatural flesh color The Fleshtone Adaptive NR detects flesh color contained in a picture and controls noise reduction coefficient to deliver optimum human flesh color RX D702 RX D402 Also applies to RX D401 Red Cr CbMi Magenta Fleshtone CbCrdif CbMa CrMa CbCrdiff Corner Cutouts Defined by ABS Cb Cr CbCrdiff Definition of Fleshtone Area in Color Vector Field Yellow Cb Blue Green Cyan ...

Page 12: ...nection 2 Superior Sound Quality Matching CD DVD User ID Learning Function Auto Scan Comparison of Signal Formats 13 14 15 16 The RX D702 permits transmission of stereo audio signals from your PC MP3 WMA Linear PCM etc for listening via your audio system The unit even permits wireless USB transmission which ensures superior near CD sound quality as well as enhanced convenience ...

Page 13: ... or A D conversion until just before output which prevents conversion loss 3 Use of DSSS Direct Sequence Spread Spectrum modulation technology enables transmission of uncompressed signals with superior resistance against noise which retains superb sound quality 4 Corresponds to 16 bit 32kHz 44 1kHz 48kHz sampling rates 5 Almost real time data transmission delay time is only 2 msec or less Note PC ...

Page 14: ...12 2 432 MHz 5 2 462 MHz 11 2 427 MHz 4 2 457 MHz 10 2 422 MHz 3 2 452 MHz 9 2 417 MHz 2 2 447 MHz 8 2 412 MHz 1 Center Frequency Channel No Center Frequency Channel No Transmitter Channel Key ID Key Auto Scan The Wireless USB additionally features Auto Scan which stops interruption from other signals in the same room When the system is turned on this function automatically detects electric waves ...

Page 15: ...rison of Signal Formats Comparison of Signal Formats Approx 600msec Under 2msec Approx 400msec Delay Time Compression No Compression 11Mbps No Compression 2Mbps Compression due to low data rate 1Mbps Format Data Rate Wifi 802 11b JVC Bluetooth Our Outstanding Points Compared with Other Wireless Products RX D702 JVC Advantages O No optional device required O Receives signals from any PC including M...

Page 16: ...onds to 16 bit 32kHz 44 1kHz 48kHz sampling rates for superior sound 2 Permits playback of any music files that can be played on the connected PC regardless of the software Windows Media Player iTunes etc 3 All digital transmission No D A or A D conversion Note PC or Desk Top PC USB Connection RX D702 RX D402 Also applies to RX D401 ...

Page 17: ...ctra Range Expansion On vs Off CC Converter How its workings differ from other high bit upsampling systems 26 28 25 26 27 24 23 22 21 20 19 18 K2 Processing is the result of a close collaboration among JVC studio engineers producers and hardware engineers embodying the elaborate algorithms for a sound quality that is close to the master by professional standards The CC Converter is one of its appl...

Page 18: ... 16 bit 12 bit 8 bit 8kHz 44 1kHz DD dts SD Cellular COMPRESSION COMPRESSION MODE MODE for MP3 WMA etc LINEAR MODE LINEAR MODE for CDs DVDs etc RX D702 JVC is not only a hardware maker but also a software producer as well so there has been a close collaboration between the hardware engineers and studio engineers for all aspects of digital sound production K2 Processing Technology is one of the man...

Page 19: ...s The process of playing digital music involves analog digital conversion and digital analog conversion as shown below Process of Playing Digital Music The sound quality of a signal depends on the following two factors when the signal is converted from analog to digital Quantization wordlength bits which determines resolution or the expression of music in the amplitude domain Sampling frequency wh...

Page 20: ...digital signal This phenomenon occurs because digital quantization distortion increases as the levels are reduced A D and D A Conversion in Amplitude Domain CC Converter CC Converter Problem An analog signal of a very faint strength cannot be accurately recreated by A D and D A conversion 1 Problem An analog signal of a very faint strength cannot be accurately recreated by A D and D A conversion 1...

Page 21: ...high order harmonics So does a square wave If the input is a 1kHz square wave signal it retains its shape because much of the information on the waveform for harmonics is retained after the A D and D A conversion But if the input is a square wave of a high frequency the converted signal presents a rounded shape because of the absence of information on high frequencies A D and D A Conversion in Fre...

Page 22: ...w level signals and 2 increasing the sampling frequency for high frequency signals Because bit expansion and oversampling alone do not guarantee better sound quality the CC Converter features JVC s original advanced digital signal processing CC Converter Block Diagram CC Converter CC Converter CC Converter CC Converter RX D702 ...

Page 23: ...he 16 bit digital signal to deduce the original analog signal before A D conversion and then applies hi bit expansion to smooth the signal waveform What s more the process ensures that the 24 bit signal preserves the same sound energy of the 16 bit digital signal Hi bit Expansion Processing CC Converter CC Converter Bit Expansion Section Bit Expansion Section RX D702 ...

Page 24: ...encies higher than 20kHz changes the waveform of audible frequencies resulting in a signal that sounds different from the original The range expansion section overcomes this problem by deducing the original waveform of a signal before A D and D A conversion and modifying the signal s waveform accordingly For playback of frequencies above 20kHz generated by this waveform processing the range expans...

Page 25: ...the audible range The CC Converter expands CD s frequency range fourfold to 88 2kHz using 176 4kHz 44 1kHz x 4 sampling frequency With DVD Video the frequency range is expanded to 96kHz while the sampling frequency is 192kHz 48kHz x 4 Therefore applying the same process for adding harmonic components is not proper in view of musicality Reviewers of European audio magazines are highly critical of t...

Page 26: ...d beyond 22kHz and higher 90dB 1kHz Sine Wave Bit Expansion On Expansion ON Expansion OFF Level dB Frequency kHz VISUAL PROOF CC Converter CC Converter Comparison of 90dB 1kHz Sine Waves Bit Expansion On vs Off Comparison of 90dB 1kHz Sine Waves Bit Expansion On vs Off Comparison of Frequency Spectra Range Expansion On vs Off Comparison of Frequency Spectra Range Expansion On vs Off CC Converter O...

Page 27: ... P E M D D Converter P E M D D Converter D D Converter RX D702 RX D402 The JVC exclusive D A converter turns the 192kHz 24 bit output into an analog signal with impeccable accuracy Also applies to RX D401 ...

Page 28: ...ng Response Noise Spectrum Conventional D A Converter Noise Shaping Response Theoretical Noise Spectrum P E M D D Converter VANS JVC Advanced Noise Shaper Response dB Frequency Hz Response dB Frequency Hz VISUAL PROOF RX D702 RX D402 Also applies to RX D401 ...

Page 29: ...l PLIIx PLIIx DTS DTS DAP 3D DAP 3D H GEQ H GEQ DRC BM DRC BM DIT DIT DIR DIR Digital IN Digital IN Analog IN Analog IN L R L R HDMI HDMI L R L R Ls Ls Rs Rs C LFE C LFE SurrBackL SurrBackL R R Digital Out Digital Out HDMI HDMI USB USB Wireless Wireless USB USB Opti Opti 2 2 Opti Opti 1 1 Coax Coax DVD Audio IN CC CC Converter Converter Opti Opti 3 3 P E M D D P E M D D Converter Converter P E M D...

Page 30: ...A D A Converter Converter A D A D Converter Converter DSP DSP Aureus Aureus TMS320DA601 TMS320DA601 Dolby Digital Dolby Digital PLIIx PLIIx DTS DTS DAP 3D DAP 3D H GEQ H GEQ DRC BM DRC BM DIT DIT DIR DIR Digital IN Digital IN Analog IN IN L R L R HDMI HDMI L R L R Ls Ls Rs Rs C LFE C LFE SurrBack SurrBack L R L R Digital Out Digital Out HDMI HDMI USB USB Opti Opti 2 2 Opti Opti 1 1 Coax Coax DVD A...

Page 31: ... measured impulse responses have difficulties recreating With JVC s DSP the sound fields are reproduced most naturally with early reflections simulated realistically More than ten years ago JVC sent engineers worldwide to measure the acoustics of famous theaters and concert halls JVC exclusive DSP embodies both the old know how and latest technologies to make you feel you are there The reason why ...

Page 32: ...tions per Second the number of floating point calculations per second performed with real numbers MIPS Million Instructions per Second A 1MIPS computer processes 1 million instructions per second An instruction is a command sent out to a DSP to directly control and operate it A DSP executes instructions stored in memory makes calculations and outputs the result The number represents a DSP or CPU s...

Page 33: ...o back JVC exclusive DSP as implemented by the TI Aureus chip embodies the algorithms of sound field recreation that are developed specifically for advanced home theater receivers The sound field patterns are created on the basis of the computer sound field simulation technology developed by a leading concert hall construction company Patterns of reflections are calculated based on the data of the...

Page 34: ...lation computations according to the configuration of speaker setting Blue ball receiver s position seating position Brown ball up front sound source stereo 2 channel 3 red balls up front sound source left right and center channels 2 red balls in the rear sound source surround left and right channels 5 1 channel surround consists of five red balls 4 green balls to the sides and in the rear 7 1 cha...

Page 35: ... Impulse Response Time Series Analysis of Simulated Hall Acoustics Sound field simulation by DSP on the other hand can produce accurate data by supplying parameters such as the shape of a hall the shape and acoustic properties of interior materials and the presence absence of an audience Because this data is not based on actual measurements that could be affected by the measuring equipment used or...

Page 36: ...s Approx 300 Reverberation 0 55 sec LIVE CLUB Capacity 400m3 Seats 70 Reverberation 0 35 sec DANCE CLUB Capacity 2 200m3 Seats 240 Reverberation 0 55 sec PAVILION Capacity 549 700m3 Reverberation 5 22 sec JVC exclusive DSP JVC exclusive DSP DAP Modes 1 DAP Modes 1 RX D702 RX D402 Also applies to RX D401 ...

Page 37: ... O PAVILION O O DANCE CLUB O O LIVE CLUB O O HALL 2 O O HALL 1 Multi Channel DAP PCM 2 ch 5 1 ch 2 ch 5 1 ch Mode Signal Analog Linear Dolby Digital DTS For 3D like reproduction of classic movies with mono soundtracks MONO FILM Small movie theater THEATER 2 Large movie theater THEATER 1 Exhibition hall with a high ceiling PAVILION Rocking dance club DANCE CLUB Live music club with a low ceiling LI...

Page 38: ...ors and capacitors therefore noise and phase reversal are inevitable A digital equalization circuit performs its function in the entirely digital domain Clarity and consistent definition are its advantages The TI Aureus chip ensures high speed processing for equalization while it executes various decode processing Dolby Digital dts etc Center Frequencies 63Hz 250Hz 1kHz 4kHz 16kHz Level 8dB 2dB st...

Page 39: ...ve algorithm that divides the audio signals into the same three elements and conducts processing individually convolution processing This ensures that sound from headphones has the same realism dynamism and localization as that from multi channel speakers Direct Sound Reflections RX D702 RX D402 Delay Delay Direct Sound Direct Sound Processing Processing Early Early Reflection Reflection Processin...

Page 40: ...ncies are raised to deliver enough loudness When the sound level is high the gains of the two frequencies are moderated to prevent excessive bass and treble output These technologies combine to retain the excitement of multi channel sound and keep dialog sound clear even at low sound levels The technologies are applied even when the sound level is lowered suddenly which is especially useful for mi...

Page 41: ...ar ear level The result is that dialog carried by the center speaker seems out of place relative to music and sound effects JVC s exclusive DSP application virtually positions the center speaker to align it with other speakers with respect to height The dialog simply sounds more natural RX D702 RX D402 Virtual Repositioning of the Center Speaker with Center Channel Alignment Also applies to RX D40...

Page 42: ... speaker from the listening position and the level of each speaker But with JVC s Smart Surround Setup Version 3 0 it takes just seconds to set up the acoustic environment of your home theater Clap your hands and the delay times of all channels are set individually and the level of each speaker is automatically trimmed optimized for your listening position You can even fine tune the settings if yo...

Page 43: ...e RX D702 and RX D402 D401 come with an upgraded Ver III device which incorporates a wide range of technological improvements for even better sound quality Problems of Digital Amplifiers 44 45 56 Hybrid Feedback Digital Amplifier Hybrid Feedback Digital Amplifier Ver Ver III III Technological Improvement for Even Technological Improvement for Even Better Sound Better Sound Low Voltage Power Supply...

Page 44: ...t ON The lower than Vref the value is the longer the pulse is left OFF Thus square shaped waves are generated representing either ON or OFF state of the pulse length of the ON and OFF pulses expresses the value of audio signals with respect to the Vref levels These waves are called PWM signals Precision of the PWM signals is one of the elements that determine the sound quality delivered by a digit...

Page 45: ...ocessor Power Power Stage Stage LC type LC type LPF LPF RX D702 RX D402 With conventional amplifiers the mechanism for digital signal processing tends to cause a wide range of noise Slew Rate Fluctuation Power Supply Noise Dead Time EMI Magnetic Distortion Error Distortion Caused at Power Stage and After Caused at Power Stage and After Even when the PWM signals are accurate a wide range of noise i...

Page 46: ... RX D402 Hybrid Feedback Digital Amplifier Use of two feedback loops eliminates the noise generated at each process Digital feedback for significantly improving the precision of PWM signal generation Analog feedback for brushing up the waveform of the analog signal at output to match the original Digital feedback for significantly improving the precision of PWM signal generation Analog feedback fo...

Page 47: ... Hybrid Feedback Digital Amplifier 2 Evolution of Hybrid Feedback Digital Amplifier 2 PWM Modulator Pre Driver Demodulator LPF Phase Shift Master Clock IN RX D702 RX D402 Hybrid Feedback Digital Amplifier Ver II Double analog feedback ensures even lower distortion Double analog feedback ensures even lower distortion 2 PWM Also applies to RX D401 ...

Page 48: ...back Digital Amplifier 3 PWM Modulator Pre Driver Demodulator LPF Phase Shift Master Clock PWM IN RX D702 RX D402 Hybrid Feedback Digital Amplifier Ver III Double analog digital feedback loops for even lower total harmonic distortion Use of newly developed JCV8015 for containing all the circuits Double analog digital feedback loops for even lower total harmonic distortion JCV8015 3 Also applies to...

Page 49: ...Low Voltage Power Supply Low Voltage Power Supply Large Capacity Power Transformer High Efficiency Stabilized Power Supply Circuit Power Supply Power Supply Digital Amp Stabilized Quality Sound RX D702 RX D402 Hybrid Feedback Digital Amplifier Ver III also features low voltage power supply which ensures stable signal transfer Also applies to RX D401 ...

Page 50: ...veloped by JVC contains all the circuits necessary for digital signal processing including dual audio input circuits the Hybrid Feedback Signal Processing Circuit and PWM modulators In addition to allowing a drastic reduction in parts and a smaller footprint JCV8015 comes with the following features Superior operational amp for low distortion and low noise High precision PWM modulator featuring sy...

Page 51: ...perational amp features a symmetrical layout of parts and devices which are completely separated for left and right channels This prevents signal interference between the two channels see the figure at right L ch R ch PAD L ch out R ch out Operational Amp with High Slew Rate Circuit for Selecting Max Modulation 2 5V Regulator Symmetrical Layout Operational Amp with High Slew Rate Circuit for Selec...

Page 52: ...els Noise is also generated when the unit receives AM signals whose frequency overlaps that of audio signals The external clock detects this and automatically modifies the audio signal frequency of all the channels simultaneously thus preventing the noise generation High Precision Triangular Waves Distortion or irregular angles of the triangular waves lower the precision of PWM signals which resul...

Page 53: ... 2 5V Regulator Analog Signals Analog GND PWM VCC Analog Power supply to digital circuits causes the current to interfere with analog GND which generates noise Digital Circuits PWM Analog Circuits Operational Amp PWM Digital Circuits PWM Analog Circuits Operational Amp 2 5V Regulator 2 5V Regulator Use of the built in 2 5V regulator prevents digital noise interference to analog GND RX D702 RX D402...

Page 54: ...wer than when input signals have higher distortion This is why JVC engineers applied a wide range of quality parts for the A V receivers These devices ensure even better sound quality by sending low distortion signals to the Hybrid Feedback Digital Amplifier Ver III RX D402 Power MOSFET used for the 150W digital amplifier of the RX D702 2SK3770 01MR IRS20124 IRFB4212 ETQA15 Power MOSFET used for t...

Page 55: ...of audio signals This frequency response of the speaker in turn fluctuates the levels of audio signals How effectively an amplifier can control these fluctuations is called speaker driveability The feedback processes of the Hybrid Feedback Digital Amplifier significantly improve the speaker driveability retaining the same output level across the frequencies VISUAL PROOF Also applies to RX D401 Spe...

Page 56: ... Digital Amplifier Hybrid Feedback Digital Amplifier Ver Ver III III T H D Comparison of Digital Amplifiers RX D702 RX D402 VISUAL PROOF Also applies to RX D401 0 004 0 01 0 1 1 10 0 001 0 01 0 1 1 10 100 Output Power W 6Ω THD N Non Feedback Amp Hybrid Feedback Digital Amp RX D702 ...

Page 57: ...RX D402B Audio Video Control Receiver RX D402B Audio Video Control Receiver RX D702B Audio Video Control Receiver RX D702B Audio Video Control Receiver 58 59 60 Rear Panel Rear Panel 62 Multi Brand A V STB CATV DBS Glow Remote Control Multi Brand A V STB CATV DBS Glow Remote Control 61 ...

Page 58: ...D Superimposed on Screen The RX D702 displays a wide range of information including the Smart Surround Setup processes superimposed on your monitor screen to ensure easy recognition and control OSD for Smart Surround Setup Setting Menu Screen Digital EQ and Bass Boost Setup Speaker Setup RX D702 ...

Page 59: ...s Connection with PC enjoy playback of music files from PC CC Converter 2 Modes Front Channels offers two modes for improving the sound quality of compressed audio and non compressed sources respectively USB Input for receiving audio signals from PC SIRIUS Input and SIRIUS Control on Remote On Screen Display Center Channel Alignment Virtual Surround Back for creating even wider sound field without...

Page 60: ...d New Digital Amplifier Product Highlights Hybrid Feedback Digital Amplifier Ver III HDMI for single cable all digital transmission of audio and video signals Video Up Conversion to HDMI for single cable output of high quality video from any input terminals USB Input for receiving audio signals from PC Center Channel Alignment Virtual Surround Back for creating even wider sound field without a sur...

Page 61: ... 61 JVC technologies for satisfying the THX Ultra2 certification Multi Brand A V STB CATV DBS Glow Remote Control Multi Brand A V STB CATV DBS Glow Remote Control For RX D702B For RX D402B RX D401S ...

Page 62: ... 62 JVC technologies for satisfying the THX Ultra2 certification Rear Panel Rear Panel RX D702B RX D402B RX D401S ...

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