Our wonderful artistic musical world has been flooded with acronym alphabet soup in the last 10 years or so. Here is a guide to help you better understand what all those techie terms mean.
AES/EBU- The digital communication format standard developed by the Audio Engineering Society and European Broadcast Union. It puts 2 channels of digital audio through an XLR connector. (Obviously, it must connect to another AES/EBU port… don’t expect any great results plugging it into your mic pre.) If you are copying DAT tapes or CDs, this might not be the format to use since it does not transmit track data (whereas SPDIF does). However, the good news is that there is no SCMS code on the signal.
Bit rate- Each time that digital audio records the amplitude of a signal, it is done with a binary number (in 0’s and 1’s.) Each 0 or 1 is a bit. The bit rate simply lets you know how many 0’s and 1’s are used to record the signal. The widely accepted standard in digital audio is the CD quality 16 bit.
CD- acronym for Compact Disc. Perhaps you’ve heard of it.
CD-R- Acronym for Compact Disc Recordable. This is a CD that you record to only once. CD-R discs will work in the majority of CD players and CD-ROMs. There are standard CD-R media, and "music" CD-R media. Instead of (or sometimes in addition to) SCMS code, some manufacturers have made CD-R devices require "music" CD media which are significantly (as much as 6 times) more expensive than regular CD-R media to prevent or help offset the cost of piracy. However, TASCAM units are designed for professionals and people making their own music, so they work with the standard, inexpensive CD-R media and override or ignore SCMS code. (i.e. CD-RW5000, CD-D4000, CD-R400)
CD-RW- Acronym for Compact Disc ReWriteable. This CD you can write, erase and rewrite over and over again. The only catch is that CD-RW doe not work in many standard CD players or CD-ROMs. However, these are still great for experimentation or assembly of a master. Almost all CD-RW drives can also read/record CD-R discs as well. (i.e. CD-RW5000)
Coaxial- In the audio industry, this is a fancy way of saying "SPDIF signal down an RCA cable." Typically, a coaxial port is an RCA connector that is set up to carry SPDIF signal. However, be aware that some devices allow you to transmit AES/EBU out of the coax part also.
DAT- Acronym for Digital Audio Tape. DAT recorders work like a cross between a CD and a cassette. The tape stores stereo digital information and can utilize track ID numbers just like a CD. DAT uses the familiar cassette transport controls, and can be written and re-written many times. (i.e. TASCAM DA-20MKll, DA-40, DA-45HR, DAP-1)
DTRS- Acronym for Digital Tape Recording System. This refers to TASCAM’s MDM recording system which uses HI-8 tapes. (i.e. DA-38, DA-88, DA-98)
EQ- Acronym for Equalizer. Most people are pretty familiar with EQ; it operates on a mixer just like it does on a home stereo. However, most people are not familiar with the different types of EQ. (i.e. parametric, sweepable, shelf, peak, etc.) Below are some basic explanations of the different types.
Boost/Cut- Boost/cut is the type of EQ found on most home stereos. It simply boosts or cuts the frequency response around a center frequency in a Bell curve fashion. The amount of boost or cut is controlled by the "Gain" dial, and the frequency given is the center frequency.
Shelf- Similar to the boost/cut, a shelf EQ is fixed in location and is a simple boost or cut. However, instead of the band-width building and falling around a center frequency , it boosts up to it, and continues boosting at the desired level until it reaches the end of our hearing potential. So, a low shelf EQ gain pattern could slope up to 80 Hz, and continue at that amount of gain all the way down to the frequency response of the mixer. The High Shelf may slope up to 12 kHz, and continue at that boost until it reaches the highest frequency response of the mixer. The amount of boost or cut is controlled by the "Gain" dial, and the frequency given is usually the frequency where the EQ first reaches its maximum level.
Sweepable- A sweepable Eq simply means the center frequency can b moved. Sweepable can be either boost/cut or shelf EQs. This is very handy because the EQ may be focused on a specific part of the studio where it may bring out more character of the signal. For instance, a High Sweep/ Shelf EQ may be focused just above the primary bands of a singer’s voice, giving them more of a breathy quality. A low sweepable boost/cut may be used to add more of a pillow sound to a kick drum, a little higher will make it punchy, and around 1 kHz you might find more kick drum beater. On a sweepable EQ, the Gain will adjust the amount of boost/cut, and the frequency will select the center of frequency of the band.
Parametric- A parametric EQ is a sweepable EQ that also gives you the ability to adjust the bandwidth. In other words, you can determine how wide an area around the center frequency you are affecting. (1/10th octave, 1/3 octave, 3 octaves, etc.) So, if you want to add a wide, smooth sounding rise in response, you can. If you want to slice out a specific, you can do that too. This is particularly helpful to remove a 60 Hz buzz, a ringing feedback frequency in a live show, or to add a little more edge to the crack of a snare drum. The controls for a parametric EQ are Gain for adjusting the amount of boost or cut, Frequency for selecting the location the location of boost or cut, and "Q" for adjusting the width of boost or cut.
Notch- A notch filter is a term used for a narrow band of EQ, typically used to "notch out" a frequency. As mentioned in the parametric EQ listing, it is typically used for removal of trouble frequencies.
I/O- This is a real cool way of saying "input and output." Also, it is the last two letters of "Old Mac Donald had a farm, E-I-E-I/O." No one knows what the E-I-E stands for, or why there are 5 spaces and only 5 vowels on that song.
Insert- An insert is also known as a "send and return." Both names aptly describe what it does. Basically, an insert point allows you to put another device into the signal flow. This way, if you have a compressor, noise gate, fancy EQ, etc. you insert it into the signal path. This is usually accomplished through a TRS plug (Tip-Ring-Sleeve), that utilizes the two channel signals as one path going in, one going out (instead of left side and right side). The signal then comes to the insert point, goes out to the connected processor, and then returns to continue down the signal path just like normal.
Jitter- Jitter is caused by multiple digital devices interconnected that can’t synchronize themselves, and samples are cut out or missing which causes audible pops or other anomalies. To prevent this, the devices will use "word clock" to keep them all together.
MDM- Acronym for Modular Digital Multitrack. Typically the units will handle up to 8 tracks, and have the capability of slaving multiple units together for larger recording systems. The two major formats for this type of machine are the HI-8 format from TASCAM, or the SVHS format from Alesis. (i.e. TASCAM DA-38, DA-88 or DA-98, or Alesis ADAT)
MIDI- Acronym for Musical Instrument Digital Interface . MIDI sends performance data that allows one synthesizer to control another. No audio is actually passed through MIDI. What MIDI sends and receives is instructions like "middle C was just played" or "the sustain pedal was pushed down." In the case of the TM-D1000, messages would be transmitted that "fader 14 was moved up" or "aux 1 on channel 12 was turned down." This way, whatever you do, a sequencer can remember that MIDI is a digital communication system, but is not used to transmit digital audio.
MMC- Acronym for MIDI Machine Control. MMC is a standard that gives transport control of MMC complaint recorders/players through standard MIDI cables. (Transport control includes things like play, stop, fast forward, rewind, record, pause, locate, and track record enabling.)
Lightpipe- The digital communication format standard developed by Alesis. It puts eight channels of digital audio through an optical cable. Don’t get an optical SPDIF signal confused with the ADAT Lightpipe… they’re not compatible. When hooking up devices with Lightpipe ports, you will need to use a TASCAM IF-TAD conversion box to convert the Lightpipe format to the TDIF format.
Optical- SPDIF and Lightpipe digital formats both travel through an optical cable (Only one at a time, please.) Remember, Lightpipe and SPDIF are not compatible formats, though. Lightpipe is 8 channels, SPDIF is 2 channels.
Sample rate- The sample rate indicates how many times per second the amplitude of a sound is recorded. Current typical standards are the CD standard 44.1 kHz (44,100 samples/second) or the higher resolution 48 kHz (48,000 samples/second.)
Sample rate converter- A sample rate converter simply allows you to change a digital signal from one sample rate to another. For instance, if a recording system is running at 48 kHz and you need to bring a CD in (which is always running at 44.1 kHz) then the sample rate converter will make the adjustment in optional one on the IF-TD1000 digital I/O expansion option. TASCAM’s CD-RW5000 does come with one, allowing sessions recorded at 48 kHz to be digitally recorded to CD.
SCMS- Acronym for Serial Copy Management System, the copy control system in digital communication. Basically, SCMS only lets you make one digital copy of a master. It was introduced to help control piracy on the consumer market. (SCMS is typically found on consumer grade equipment.) However, professionals in the audio industry need to make copies of things for many reasons. So, most TASCAM Pro equipment can either override or ignore SCMS code, allowing you to distribute your masterpiece without restriction.
Snapshot- Once a mix is set up on the mixer, all of the settings can be stored and recalled.
SPDIF- The digital communication format standard developed by Sony and Philips. (SPDIF stands for Sony/Philips digital Interface.) It puts 2 channels of digital audio through an RCA connector (coaxial) or an optical cable. Yes, this one has two different cables which carry it. (Obviously, it must connect to another SPDIF port - don't expect any great results plugging it into your vintage 1973 8 track.) Don't get an optical SPDIF signal confused with the ADAT Lightpipe either… they’re not compatible. When working with consumer digital players/recorders, SPDIF sometimes caries SCMS code on it. SPDIF can also carry track number data for DAT players and CD players/recorders which is one advantage of SPDIF over AES/EBU.
TDIF- Acronym for TASCAM Digital Interface. The digital communication format standard developed by TASCAM. TDIF provides for 2 way communication of 8 channels of audio through a DB25 plug. A TDIF cable is not the same as a SCSI, parallel, or any other 25 pin cable. Use only with approved TDIF cables to ensure proper operation.
Transition time- The TM_D1000 has the capability of crossfading into a scene or between scenes. (The only thing that crossfades is volume. Everything else snaps upon recalling the scene.) The duration of that crossfade is called the transition time. On the TM-D1000, the transition time is adjustable from 0 to 10 seconds in 1/10th of a second intervals.
Word clock- (If you don’t have a firm grasp on sample rates and bit rates, see Section II - Crash Course in Digital Audio.) When multiple devices are connected digitally, they need to synchronize their sample rates. Each digital sample makes up one "word." So, the word clock basically makes sure that all the devices are transmitting their digital information at the same time to prevent "jitter" problems. Remember, you’ll probably be needing to synchronize 44,100 or 48,000 samples every second from EACH source channel. It is important to realize that only one device can be the master, and all of the others will follow that master.