Extended Resolution Compact Disc
Encyclopedia
eXtended Resolution Compact Disc (XRCD) is a mastering and manufacture process patented by JVC
JVC
, usually referred to as JVC, is a Japanese international consumer and professional electronics corporation based in Yokohama, Japan which was founded in 1927...
(Victor Company of Japan, Ltd) for producing redbook
Red Book (audio CD standard)
Red Book is the standard for audio CDs . It is named after one of the Rainbow Books, a series of books that contain the technical specifications for all CD and CD-ROM formats.The first edition of the Red Book was released in 1980 by Philips and Sony; it was adopted by the Digital Audio Disc...
Compact Disc
Compact Disc
The Compact Disc is an optical disc used to store digital data. It was originally developed to store and playback sound recordings exclusively, but later expanded to encompass data storage , write-once audio and data storage , rewritable media , Video Compact Discs , Super Video Compact Discs ,...
s. It was first introduced in 1995.
A XRCD is priced about twice as high as a regular full-priced CD. JVC attributes this to the higher cost of quality mastering and manufacturing.
Technical overview
The XRCD definition refers to the mastering and manufacture process; the resulting CD and the contained data conform to the redbook standard and are encoded at 16 bitBit
A bit is the basic unit of information in computing and telecommunications; it is the amount of information stored by a digital device or other physical system that exists in one of two possible distinct states...
s, 44.1 KHz. Hence, XRCDs are playable on any compact disc player.
JVC uses advanced dither
Dither
Dither is an intentionally applied form of noise used to randomize quantization error, preventing large-scale patterns such as color banding in images...
algorithm
Algorithm
In mathematics and computer science, an algorithm is an effective method expressed as a finite list of well-defined instructions for calculating a function. Algorithms are used for calculation, data processing, and automated reasoning...
s (though without noise shaping
Noise shaping
Noise shaping is a technique typically used in digital audio, image, and video processing, usually in combination with dithering, as part of the process of quantization or bit-depth reduction of a digital signal...
) in their proprietary K2 technology to transfer the analog or digital source to physical disc. The company claims to have studied how inferior CD-remastering techniques degrade the master tape sound and strives to minimize this loss.
Mastering process
If analogAnalog recording
Analog recording is a technique used for the recording of analog signals which among many possibilities include audio frequency, analog audio and analog video information for later playback.Analog recording methods store signals as a continual wave in or on the media...
, the source material is first converted to digital via JVC's patented K2 20-bit
Bit
A bit is the basic unit of information in computing and telecommunications; it is the amount of information stored by a digital device or other physical system that exists in one of two possible distinct states...
or 24-bit analog-to-digital converter
Analog-to-digital converter
An analog-to-digital converter is a device that converts a continuous quantity to a discrete time digital representation. An ADC may also provide an isolated measurement...
.
The musical information is next encoded on a magneto-optical disk for transport to JVC's Yokohama
Yokohama
is the capital city of Kanagawa Prefecture and the second largest city in Japan by population after Tokyo and most populous municipality of Japan. It lies on Tokyo Bay, south of Tokyo, in the Kantō region of the main island of Honshu...
manufacturing plant, where jitter
Jitter
Jitter is the undesired deviation from true periodicity of an assumed periodic signal in electronics and telecommunications, often in relation to a reference clock source. Jitter may be observed in characteristics such as the frequency of successive pulses, the signal amplitude, or phase of...
reduction is applied. The musical signal on the disk is down-converted to 16-bit through a K2 "super-coding" process. This 16-bit signal is EFM
Eight-to-Fourteen Modulation
Eight-to-fourteen modulation is a data encoding technique – formally, a channel code – used by compact discs and pre-Hi-MD MiniDiscs. EFMPlus is a related code, used in DVDs and SACDs. EFM and EFMPlus were both invented by Kees A...
-encoded before going through a proprietary "Extended Pit Cut" DVD K2 laser technology to produce a glass master. This optimizes the linear velocity of the glass master, giving precise pit lengths to eliminate time jitters, controlled by an extremely precise Rubidium
Rubidium
Rubidium is a chemical element with the symbol Rb and atomic number 37. Rubidium is a soft, silvery-white metallic element of the alkali metal group. Its atomic mass is 85.4678. Elemental rubidium is highly reactive, with properties similar to those of other elements in group 1, such as very rapid...
clock. All CDs are finally stamped directly from this glass master.
XRCD2 and XRCD24 are improved versions of the original XRCD process. XRCD2 is the first to record to a magneto-optical disk via the digital K2 regenerator, while XRCD24 upgrades the original music signal's bit depth
Bit depth
Bit depth may refer to:* For bit depth in graphics, see color depth* For bit depth in audio, see audio bit depth* For bit depth in drilling for petroleum, see drilling rig...
signal from 20 to 24 bits.