040, 030, 020@Computing industry jargon, referring to specific models within the Motorola 68000 family of processors, the Motorola 68040, 68030, and 68020, commonly used as CPU chips in the Apple Macintosh (and other computers) before the current PowerPC-based models (PowerMac). See also 680X0, CPU.@1-bit sigma/delta conversion@An intermediate step in oversampling A/D converters, where audio which has been converted to a very high sampling rate is encoded at 1-bit, and a sigma-delta modulator is used to create noise shaping for a dithering signal. Later, as in all oversampling methods, the data passes through a digital lowpass filter and is then decimated (divided) back to the output sampling rate of 44.1 kHz or 48 kHz which is used for storage of the audio data. The design requirements of the Anti-Aliasing lowpass filter are simplified by use of this intermediate 1-bit coding at the higher sample rate, and higher sound quality is achieved with less coloration. Therefore, all high-quality digital audio devices incorporating Oversampling will also tend to use this technique to further reduce quantization noise. See Oversampling, Signal-to-Error Ratio, Quantization, Noise Shaping, Dithering.@1/4" Phone, Quarter-Inch@A type of connector (plug=male and jack=female) used for audio, named phone because it was found on the connection cables for the original, manually-operated telephone switchboards. There are two basic types, two-wire (Tip/Sleeve or T/S), and three-wire (Tip/Ring/Sleeve, or TRS). A "male" 1/4-inch phone plug (T/S) is found on electric guitar and other musical instrument cables, it is inserted into the corresponding female "jack" on an amplifier, mixer, etc. "Phone" connectors (1/4" and 1/8") should not be confused with "phono" connectors (also known as RCA connectors). See also T/S, TRS, RCA, XLR.@1/8" Phone, Mini Phone@A type of audio connector. Frequently used on computers and their sound cards, as well as for headphone jacks on personal cassette players. There are two basic types, two-wire (T/S, Tip "Hot" and Sleeve "Ground"), and three-wire (TRS, Tip "Right" Ring "Left" and Sleeve "Ground"). "Mini" connectors are relatively fragile, and don't provide reliable contact for good signal transmission; for this reason they are rarely used on professional equipment, unless absolutely necessary for space considerations. As with all audio conectors, the "male" connector is called a plug, the "female" is a jack.@10BaseT@A type of Ethernet cabling used for local area networks. 10BaseT networks use four-conductor twisted-pair "telephone" cables with RJ45 connectors (these look like an oversized version of the RJ11 modular connectors used for ordinary telephones). The cables are attached to centralized cabling concentrators (small "hubs" with multiple ports, from which multiple workstation cables are extended). The name comes from 10 megabits per second (mbps) running over Twisted Pair. 100 mbps variations are also available. See Ethernet.@1224@External audio interface for Mac and Windows computers, by Mark of the Unicorn (MOTU). 8 analog inputs, 8 analog outputs, with TRS balanced connectors, plus 2 "Main Outs" with balanced XLR connectors. 24-bit analog/digital conversion. AES/EBU digital I/O can be used simultaneously with (and independently from) analog I/O, for a a maximum of 10 record inputs, or 12 outputs (including Main Outs). Features Word Clock In/Out, and "Audio Wire" connector for connection to PCI card in host personal computer (PCI-324). Supports ASIO drivers.@1630 Transfer@A common intermediate step in the manufacturing of CD's, where the audio and subcoding is transferred from the original submitted master to a Sony 3/4" U-Matic video tape, via either analog input to PCM hardware, SDIF-2 or optionally AES/EBU digital. The audio data is digitally encoded into the video signal area, while the subcoding is recorded onto the U-Matic analog audio track. This tape is then played back in real time while writing the "glass master"; it can be stored and replayed if any error is detected subsequently. 1630 Transfer is the original CD mastering format, and is still the most commonly used method. Many CD manufacturing houses charge separately for this transfer step. It can be eliminated by submitting a properly formatted CD-R disc (see definition) as the master, containing all the Red Book subcoding information necessary to produce the glass master. See also Mastering, Red Book, MasterList CD, PCM, CD-R, Glass Master.@22K@Short for 22 kilohertz (22 kHz), a common sampling rate used for digital audio in computer applications, but beware! Currently the accepted "22K" rate is 22,050 Hz, especially where the audio must be compatible with various computer platforms. However, the original "22K" rate used by Macintosh computers (which is still seen in some applications) was 22,254 Hz. Later Macintosh models now use the 22,050 rate. If you need to convert (downsample) audio from 44.1 kHz to "22K" for an interactive "multimedia" application, you will achieve better-sounding conversions and have better options for cross-platform compatibility if you use the 22,050 sampling rate.@2408@External audio interface for Mac and Windows computers, by Mark of the Unicorn (MOTU). 8 analog inputs, 8 analog outputs, plus 2 "Main Outs", all with balanced TRS connectors. 24-bit analog/digital conversion. S/PDIF digital I/O, plus three 8-channel ADAT Optical connectors (fiber-optic), and three 8-channel Tascam TDIF connectors (25-pin) Maximum of 24 record inputs, or 24 outputs (including Main Outs). Features Word Clock In/Out, and "Audio Wire" connector for connection to PCI card in host personal computer (PCI-324). Supports ASIO drivers.@2x, 4x, Quad Speed, 6x, 20x, 32x, etc.@Computing industry jargon. A means of ranking data Transfer Rates of different CD-ROM drive mechanisms, by comparing them to the original generation of Apple CD-ROM drives, which transferred data at 150 Kilobytes per second (Kbps). Therefore, a 2x drive transfers at 300 KBps, a 4X (quad) drive 600 KBps, and a 6x drive 900 Kbps. In actual practice, one of the slowest aspects of CD-ROM drives is their very slow Seek Time (see definition), commonly on the order of 175 to 235 milliseconds (ms), versus access times of less than 20 ms on any current hard disk. The relative importance of Access Time, versus Data Transfer Rate, will depend on the nature of the data being accessed. For digital audio and video, it is more typical to access a smaller number of very large files. The Sustained Transfer Rate of the CD-ROM drive may be even more important than Access Time (especially for programs that play back a single audio file at a time). Once the read/write head locates the beginning of the desired file, it must retrieve a very large amount of data in the individual file, residing on contiguous (adjacent) sectors of the disc's surface. See also CD-ROM, Seek and Access Time, Transfer Rate.~@32-bit addressing@Macintosh term. 32-bit addressing increases the length of the numbers used to designate locations in RAM. (Or, to be precise, the number of binary digits in the data word representing each memory address is increased from 24 to 32.) Necessary for the Macintosh operating system to recognize memory capacities greater than 8 megabytes; up to 1 gigabyte of RAM (1,024 megabytes). Incidentally, 32-bit addressing also enables the use of Virtual Memory, another option in the Memory control panel Some older Macintosh models (SE/30, MacII) and operating systems required a system Extension called MODE32, to recognize more than 8Mb RAM.@442 Audio Card@The 4-channel NuBus card at the heart of the original Macintosh-based Pro Tools 442 system (Pro Tools "I"), now discontinued. Each 442 Audio Card incorporated two Motorola DSP56001 chips, with a 50-pin connector for a cable linking each 442 Audio Card to its corresponding 4-channel 442 I/O Audio Interface. Therefore, a basic 4-channel Pro Tools 442 system consisted of a 442 Audio Card, 442 I/O Audio Interface, the cable to connect them, plus the Pro Tools software. (Unlike the Disk I/O card for Pro Tools III systems, the 442 Audio Card did not include a SCSI connection; disks were attached to the Mac's SCSI chain, or to the System Accelerator card in 442 systems with 8, 12, or 16 channels). In older Digidesign manuals and "Read Me" documents, sometimes also referred to as simply the "Pro Tools Audio Card", or the "SA4" card. See also 442 I/O.@442 I/O Audio Interface@Four-channel external audio interface for now-discontinued Pro Tools 442 and Sound Tools II systems (Session 8 XL also used two of them). Four balanced XLR analog inputs and outputs at +4dBm line level, stereo digital inputs/outputs which could be selected between AES/EBU and S/PDIF ports. This was Digidesign's original 4-channel audio interface, it was connected by a 50-pin cable to the 442 Audio Card. In older Digidesign manuals and "Read Me" documents, the unit is sometimes also referred to as the Digidesign Audio Interface, Pro Tools Audio Interface, and Quad Interface. (A note regarding naming conventions for Digidesign's audio interfaces: the first number corresponds to simultaneous analog input channels, the second corresponds to analog outs, and the third number specifies the simultaneous digital input/output channels - for example 442, 882, and 888.)@5-node TDM Ribbon Cable, 12-node@Digidesign Pro Tools term. A thin, flexible cable used to interconnect TDM-compatible cards from Digidesign and/or other manufacturers, within TDM-equipped Pro Tools systems. The ribbon cable is the physical link for sharing of data between cards on the TDM Bus. Each TDM-compatible card features a multi-pin slot where a corresponding "node" connector on the TDM Ribbon Cable can be attached. See also TDM Bus.@5:1@A surround sound format. "5:1" is a subset of the Dolby AC-3 sound playback standard (a.k.a. "Dolby Digital"). It is used in "home theater" surround sound content (and playback systems). Five channels of audio information (left, center, right, left rear, right rear) and one active sub channel (the ".1" in the name) are multiplexed into the audio track. 5:1 has emerged as the de facto standard for audio on DVD video releases for the consumer market.@601, 603, 603e, 604@Models of the PowerPC processor, manufactured by Motorola. The 604 chip was about 50% faster than a 601 processor running at the same clock speed (in megahertz), and also supported higher clock speeds (up to 350 MHz) than other PowerPC chips. The 601 was the first PowerPC chip to reach the market; it offered more processing power than the 603 and 603e, which are being used by Apple on many of their Power-PC based Macintosh Performa and PowerBook computers (previous models were based on processors from the Motorola 680X0 family). The 603 processors were about 25% less powerful than a 601 processor at the same speed. The 604e processor was introduced in 1996, supporting higher clock speeds than the original 604, doubling the onboard instruction cache from 16Kb to 32Kb, and adding a fourth integer unit, further speeding calculations. The 604e and 603e were therefore faster than 604 of 603 processors operating at the same clock speed. In later Macintosh models, all of these processors were replaced by the more powerful G3 processor. See also PowerPC, 680X0.@680X0, 68K@Computing term. Collectively refers to the Motorola 68000 "family" of processors, the 68000, 68020, 68030, 68LC040 and 68040, which were used extensively as "CPU" chips in all models of Macintosh computers prior to the PowerMac. (This series of CPUs was also used in Atari, Amiga and Sun computers, as well as various PostScript laser printers and NuBus cards from Digidesign and other manufacturers.) In contrast, Apple's PowerMac models are based on the PowerPC chip, and feature a "68K Emulation" mode to promote compatibility with programs written for this prior generation of processors. The 68K emulator, or intrepretor, is a set of programming routines built into the ROM of PowerMac computers. See also PowerPC, CPU.@8-pin@A standard, rectangular plug and socket format, used to connect professional video equipment to video monitors or receivers. The 8-pin cable carries video, audio and other signals, and features two locking buttons on either side of the plug, which prevent this cable from being accidentally unplugged.@882 I/O Audio Interface@Digidesign product. External 1-unit rackmounted audio interface for Pro Tools systems, available in 16- or 20-bit models. Connected to the audio/DSP card in the computer via a 50-pin cable. External power supply. Eight analog inputs and outputs (1/4" TRS balanced), globally switchable between -10 and +4 line level, plus a single S/PDIF digital interface. (A note regarding naming conventions for Digidesign's audio interfaces: the 1st number designates simultaneous analog input channels, the 2nd designates analog outs, and the 3rd specifies the number of simultaneous digital input/output channels. That's why the current Digidesign audio interfaces are called 442, 882, and 888.) See the "Installation" section of the Pro Tools module, on the Cool School Interactus CD-ROM Vol 1, for detailed information regarding the 882 I/O interface.@888 I/O Audio Interface@Digidesign product. External rackmounted audio interface for Pro Tools, available in 16- or 24-bit models. Occupies two rack spaces, internal power supply, 15-segment LED metering on front panel. Eight analog inputs and outputs with balanced XLR connectors at +4dBm line level (channel-switchable to -10dBV via internal jumpers, fine adjustment of in/out level is provided via multi-turn cermet trims, which are inset on the front panel), plus (4) stereo AES/EBU and (1) S/PDIF digital interfaces. A note regarding naming conventions for Digidesign's audio interfaces: the 1st number designates simultaneous analog input channels, the 2nd designates analog outs, and the 3rd specifies the number of simultaneous digital input/output channels. That's why the current Digidesign audio interfaces are called 442, 882, and 888. Therefore, as you may have guessed, the 888 I/O provides up to eight channels of digital input/output through its four stereo AES/EBU ports.@
