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The Audio Engineers Dictionary F-M
| FAQ | Frequently asked questions. | |
| FAT | Computer | File Allocation Table |
| femto | SI Units | prefix Symbol f Eg femtogram (fg) = 0.000000000000001grams Or 10^-15 |
| field | Video | with the normal interlaced video method each picture frame comprises 2 fields, one with only the even No lines the other only odd number lines |
| file | Computer | A named collection of data, usually stored on a disk drive. |
| file compression | Computer | Eg WinZip. Software to make files smaller with no loss of data. The file will need to be re-expanded before it can be used. |
| file suffix | Computer | Typically 3 letters after the filename that indicate what type of file & therefore what application is needed to run the file. Eg xxx.DOC is a MS Word document, xxx.MID is a MIDI file |
| filename | Computer | 8 to 255 {depending on the Disk operating system} alphanumeric characters used to name a file. |
| filter | Circuit that attenuates certain portions of the audio frequency spectrum | |
| firewall | Computer | A secure gateway that protects a network from unauthorised access by making the machines behind the firewall invisable. |
| Firewire | Computer | Most popular name {(r) Apple Computer} for IEEE1394, a High speed 400 megabits per second Plug & play Serial connection {Sony call it I.LINK,(r)} |
| flame | Computer | Derogatory & often offesive comment re an E-mail. A flame war being an on line argument/row. |
| Flanging | Comb fitering effect originally achieved by mixing 2 tapes playing the same recording in sync and by touching the flanges of the tape spool so as to slow down one of them. The results causes predominantly a heavy phasing effect. | |
| Fletcher Munsen Curves | acoustics | aka Equal loudness curves, statistical analysis of human subjective impression of loudness V frequency |
| floating point | Computer | radix or a decimal point that does not occupy a fixed position within a given word |
| floppy disk | Computer | Removable data storage. Generally < 2Mb. Older disks of 8 or 51/4 diameter were floppy the current 3.5 discs have a hard shell. |
| floptical drive | Computer | Derived from FLoppy OPTICAL. A disc drive using a mixture of Laser & magnetic techniques. Up to 1.3g in size |
| FM Synthesis | Frequency Modulation Synthesis. When one waveform modulates another to create a new one. Repeated many times in order to reproduce real organic sounds. | |
| folder | Computer | A collection of Document and program files can be stored in folders. In DOS & early Windows was called a directory. |
| Foley | Film | Post syncing Fx.Eg footsteps or rustling clothes, in sync with the picture. Named after Jack Foley one of its first practitioners. |
| FPGA | Computer | Field Programmable Gate Array; Chip with thousands of programmable logic gates, often used for prototypes & custom designs Eg DSP |
| fps | Film TV | Frames Per Second |
| Freemidi | MIDI | Similar system to OMS. |
| freeware | Computer | Software that the author/owner licences one to use without charge |
| Frequency | Number of cycles in a periodic wave per second; measured in Hertz {Hz} | |
| FTP | Computer | File Transfer Protocol. Part of TCP/IP data tranmission protocol designed for binary files rather than Text |
| Fundamental Frequency | acoustics | The perceived tone or pitch of a complex waveform (IE one consisting of multiple frequencies) |
| gain | Electronics | amount of amplification generally expressed in dB's |
| game port | Computer | Uses a 15pin D connector, for analog joystick control. On a PC also MIDI I/O |
| Gate | Fx Units | a dynamics unit that greatly reduces signal level output when the input signal falls below a set threshold level |
| Gateway | Computer | Link between two different kinds of network with the ability to modify IP addresses and route signals. |
| Gflop | Computer | Giga Flop = 100,000,000 Floating point mathematical operations per second |
| GIF | Computer | Graphical Interchange Format; Graphics format from CompuServe (r) 256 colours IE 8bits/ pixel. Popular on WWW |
| giga | SI Units | prefix Symbol G Eg gigagram (Gg) = 1,000,000,000grams Or 10^9 |
| Gigabyte | Computer | 1,073,741,824 Bytes {1024^3} or 2^30 {sometimes = 1,000,000,000} |
| Glass Master | Computer | Glass Mastering is the process of transferring the CD master (either on PCM-1630 tape, recordable CD, or Exabyte tape) to a physical image of the pits that are on the finished CD. The glass master is a glass plate, about 10 in diameter, coated with a light-sensitive material. During glass mastering, a laser etches very tiny pits on the material. When the master tape is played, its digital signals are converted to the EFM coding format for the CD, and that signal is fed to the special laser cutter. The glass master is very delicate, and cannot be played. Succeeding steps in the process, called Father, Mother, and Stamper, result in the metal forms which are capable of hot molding thousands of compact discs on the presses. |
| gobo | A baffle {US Eng but also used in UK} | |
| Computer | The best search engine I have found | |
| Googol | Computer | 10^10 IE 1+ 100zeros |
| ground | {US Eng but widely used in UK} {UK Eng= Earth} aka Zero Volts A connection, Eg from the chassis to Terra Firma to remove mains voltage in a fault condition or RF interference | |
| GUI | Computer | Graphical User Interface. Was know as WIMP; Windows, Icons, Mouse & Pointer. Eg Mac Os & MS Windows |
| Guide track | Film | G/T; sync recording of dialogue etc but where it assumed the track will not be of usable quality generally because of technical reasons |
| gun mic | Microphones | Highly directional though mostly at higher frequencies. Widely used for speech recording for Film/TV |
| Haas effect | Acoustics | If two sound waves identical apart from a delay to 1 of them are created only the earlier of the 2 will be heard. Unless delay is greater than about 30 ms then discrete echoes are heard. |
| HAL | Computer | Hardware Abstraction Layer; part of the operating system that lets programs communicate directly with hardware rather than though an API. hard work to program but can run much faster |
| handshaking | Computer | The use of bi-directional data flow to confirm the successful transmission of data |
| hard disk | Computer | hardware usually inside the computer to store data as magnetic patterns on rigid magnetic discs. Was know as a Winchester disk |
| hardware | Computer | physical or 3 dimensional components of a computer system Eg Disks, case, PSU etc |
| Harmonics | Acoustics | aka Overtones. Most waveforms consist of the fundamental note + a number of other frequencies or harmonics that define the timbrel character of the sound |
| Harmonizer | Pitch Shifter (r) Eventide. Can sample and playback at a different pitch/speed any input sound virtually in real-time. Good for making artificial harmonies. | |
| Hayes AT command set | Computer | Commands devised by modem manufacturer Hayes. Are de facto standard for software which controls modem comunication. |
| hecto | SI Units | prefix Symbol h Eg hectogram (hg) = 100grams Or 10^2 |
| Helmholtz resonator | reactive, tuned, sound absorber usually employing slats or perforations over a cavity. | |
| Hertz | Unit for Frequency (Hz) same as Cyles per second (cps) named after Heinrich Hertz | |
| Hexadecimal | Computer | Base 16 numbering system. Uses 0-9 then the letters A-F for the 16 characters. |
| HF | High Frequencies | |
| High Resolution Controller | MIDI | Midi message combining 2 data bytes (MSB and LSB) to express one 14 bit value (16384 possibilities) |
| highpass filter | HP;=Bass cut | |
| hole in the middle | bad central phantom image in stereo playback. | |
| host | Computer | a computer acting as a server (to a client) |
| HRTF | Acoustics | Head Related Transfer Function; the Eq'ing effect caused principally by our outer ear that changes vis-�-vis the angle from which the sound originates |
| HTML | Computer | Hypertext Markup Language. A text document that contains embedded tags to control formatting Eg cause text after that point to be in bold. |
| HTTP | Computer | Hypertext Transport Protocol. Used on the WWW to make hypertext links. |
| hypercardioid | Polar pattern (Eg of a Mic), -9dB @900 | |
| hypertext | Computer | A document containing links to other documents. |
| Hz | Analog | Hertz same as CPS |
| I/O | Computer | Input / Output |
| IE | Id Est (Latin) that is to say | |
| IEC | International Electrotechnical Commission | |
| impedance | Opposition to the flow energy in any system using oscillating energy. Eg Sound or AC signals. | |
| incus | The Ear | One of 3 ossicles that convey eardrum vibrations to the cochlea |
| inductance | Electronics | Symbol L; ability of a conductor to store energy as a magnetic field |
| infrasound | acoustics | LF below audible range |
| inner ear | The Ear | cochlea |
| integer | maths | a whole number IE not including a fraction |
| intensity | Amplitude | |
| intensity | Acoustics | intensity is the sound energy flux per unit area. |
| Intensity Probe | Acoustics | 2 closely spaced pressure mics used, from which is calculated sound velocity = their difference (corrected for air density & mic spacing) X Averaged sound pressure of the 2 mics. |
| intensity stereo | Conveying the direction from which a sound originates purely by level differences Eg A coincident stereo Mic pair, a pan pot | |
| interaural | acoustics | Difference in information received by a pair of ears |
| interference | Electronics | Unwanted crosstalk, generally by induction, into a system |
| interference | Acoustics | Constructive or destructive summing of 2 or more sound waves |
| Interlace | Video | To get a reasonably low bandwidth & a tolerable flicker rate it was decided to split each picture into 2 fields, using odd & then even lines |
| inverse square law | Acoustics | The intensity of sound diverging spherically from a point in free space decreases inversely as the square of the distance. Sound pressure, varies as the first power of the distance. Thus sound pressure decreases 6 dB with each doubling of the distance in free space. |
| Ion | Electronics | Electrically charged atom(s) with an unequal number of protons (positively charged particle in an atom's nucleus) and electrons (negatively charged particle circling the nucleus) |
| IRQ | Computer | Interrupt ReQuest; each of the many devices in a computer has to issue an Interrupt to have a turn at using the CPU |
| ISDN | telecom | Integrated Services Digital Network; 64kb/sec down same cable as POT |
| ISO | International Standards Organisation | |
| Java | Computer | Programming language not tied to a specific operating system. |
| Java Script | Computer | Unrelated to Java but a programming language much used on the WEB |
| Jitter | Computer | Timing variations Eg in a digital audio clock. |
| JPEG | Computer | Joint Photographic Experts Group, Data reduced Graphics format popular on the WWW. Unlike GIF can suport photo quality images |
| kB | Computer | Kilobyte. 1024 Bytes 2^10 Sometimes = 1,000 Bytes |
| Keykode | Film | Digital, machine readable alpha numeric code on original negative. Like the human readable edge numbers |
| kilo | SI Units | prefix Symbol k Eg kilogram (kg) = 1000grams Or 10^3 |
| KVM switch | Computer | Keyboard Video Mouse; means of making 1 KVM control many Computer |
| LAN | Computer | Local Area Network. A collection of interconnected Computer within a few hundred metre area |
| LCD | Electronics | Liquid Crystal Display |
| LED | Electronics | Light Emitting Diode; semi-conductor that glows |
| LF | Low Frequencies. If audio this means Bass | |
| LFO | Low Frequency Oscillator | |
| Lightworks (r) | Film | Microprocessor based non linear editing system for pictures & sound |
| Linux | Computer | UNIX-like operating system originally developed by Linus Torvalds, It's open source IE freeware |
| live acoustic | Acoustics | Reverberant space or room |
| Local Control | MIDI | Internal message sent from a keyboard to its own in-built sound module. |
| log on | Computer | Connecting to a host computer.Generally with password protection |
| lowpass filter | Electronics | LP; = Top or high frequency Cut |
| LPCM | Digital | Linear Pulse Code Modulation. Common system of encoding an analog signal where the amplitude of the signal sampled at the Nyquist rate is directly converted to a binary number. Eg as on CD |
| LPF | Electronics | Low Pass Filter: will remove High Frequencies. Very popular in current dance music when swept. |
| LSB | Digital | Least Significant Byte or Bit depending on context. |
| LTC | Digital | Longtitudinal Time Code; the most common physical form for SMPTE/EBU t/c to take. For recording on a normal analog soundtrack. See MTC, VITC |
| Luminance | Video | Black & White information of a video signal. Abbreviated as Y |
| LZW | Digital | Limple Ziv Welch, lossless data reduction algorithm |
| M&E | Film | Music & Effects (track) As the final mix of a film but minus dialogue Sometimes aka International version |
| Mac OS | Computer | Apple Macintosh (r) Operating System |
| MacBinary | Computer | File format that combines Macintosh Finder info with the data and resource forks |
| Macintosh (r) | Computer | Personal computer introduced in 1984 by Apple. |
| Macrovision (r) | Video | Video copy protection that rapidly modulates colourburst signals and pulses the vertical blanking signal in order to make videotape copies of protected material unwatchable |
| malleus | The Ear | 1 of 3 ossicles that convey vibrations to the oval window of the cochlea |
| masking | Process by which the threshold of audibility of one sound is raised by the presence of another sound | |
| MB | Computer | Megabyte 1,048,576Bytes (2^20) Sometimes = 1,000,000 Bytes & sometimes either number of bit/sec |
| Mb | Computer | Megabit 1,048,578 Bits Or 131,072.25 Bytes Not consistently written so may mean Bytes |
| MDM | Modular Digital Multitrack. Eg Adat, DTRS typically low cost 8Track ATR's that can be easily synced together to form say 128 track capability | |
| meatus | The Ear | Ear Canal |
| median plane | Straight ahead. The vertical plane equidistant from the two ears bisecting the head | |
| mega | SI Units | prefix Symbol M Eg megagram (Mg) = 1,000,000grams Or 10^6 |
| Metadata | Computer | data about data. |
| Metafile | Computer | An image file that can contain a mix of bitmapped or raster image data & vector info. |
| micro | SI Units | prefix Symbol � Eg microgram (�g) = 0.000001grams Or 10^-6 |
| micron | Commonly used {in theory obsolete} name for �m Eg millionth of a metre = 0.000001m Or 10^-6 | |
| microphone | microphones | Device that transduces air vibrations into corresponding electrical signals. Aka Mic |
| Microprocessor | Computer | A CPU, Central Proccessing Unit, the computational engine or brain. |
| microtone | a musical interval less than a semi-tone on the equal tempered scale | |
| middle ear | The Ear | Portion of the ear between the eardrum and the cochlea. |
| MIDI | MIDI | Musical Instrument Digital Interface; sends performance data not actual sounds |
| MIDI channel | MIDI | 16 available per MIDI port. Each channel can carry it's own independent information. |
| MIDI Clock | MIDI | A systems common message sent out on every beat. Used by software sequencers to control drum machines, arpeggiators and any other timing dependent devices. |
| MIDI Connector | MIDI | 5 pin DIN plug, all 5 pins being in a 1800 Semi circle. Only 3 pins used |
| MIDI In | MIDI | Port receiving MIDI messages from the outside world. |
| MIDI Interface | MIDI | Hardware generally with multiple MIDI In and Out ports, each carrying 16 channels of information. Often connected to the computer via USB |
| MIDI Modes | MIDI | 1: omni polyphonic 2: omni monophonic 3: responds to 1 channel polyphonically 4: responds to 1 channel monophonically |
| MIDI Out | MIDI | Port sending MIDI messages generated within the unit to the outside world. |
| MIDI Thru | MIDI | Port re-transmitting incoming MIDI messages to the outside world. |
| mid-side | microphones | See MS |
| milli | SI Units | prefix Symbol m Eg milligram (mg) = 0.001grams Or 10^-3 |
| MIME | Computer | Multi-purpose Internet Mail Extensions. A standard for sending Binary files in ASCII form via the Internet. |
| mixdown | Process in which a multichannel recording is combined into 1, 2 or more channels for loudspeaker or headphone listening. | |
| MLP | Digital | Meridian Lossless Packing, Lossless data reduction algorithm. Part of the DVD-A specification |
| MMC | MIDI | MIDI Machine Control - Systems Common messages carrying transport information via the MIDI protocol |
| modem | Computer | MOdulator/DEModulator. Hardware to allow digits to be sent via a Plain Old Telephone line. |
| modes | Acoustics | Low-frequency resonances (modes) prominent in small rooms |
| mono | Contraction of monophonic / monaural | |
| mono compatibility | An acceptably low level of distortion (particularly Comb Filtering) where a stereo mix is heard as a mono sum of the L+R channels | |
| Monophonic | MIDI | Not polyphonic. Can only play one note at a time. |
| Monophonic | Mono, sound recording carrying 1 channel of information. | |
| Monotimbral | MIDI | Not multitimbral. Can only play one sound at a time. Responds according to one of the 4 MIDI Modes. |
| mouse | Computer | Mechanical device to control an on screen pointer. 1 or more buttons can select control options. |
| Mp3 | Digital | MPEG-1 Audio Layer 3. Lossy data reduction scheme for mono or stereo |
| MPEG | Film | Moving Pictures Expert Group |
| MS | Microphones | Intensity Stereo technique where information is conveyed as a Sum (L+R, the Main channel) & Difference (L-R, the side channel). As a Mic technique the Main pickup will be via any Mic pointing at sound source & Side by a L/R facing Fig 8 Mic. |
| MS (r) | Computer | Microsoft. Software corporation responsible for DOS, Windows + applications such as Word/Excel |
| MSB | computer | Most Significant Byte or Bit depending on context is the one representing the greatest quantity |
| MSN | Computer | Multiple Subscriber Number; an ISDN line can have more than one number associated with it, useful for directing calls to specific bits of kit - phone, fax, PCs etc. |
| MTC | MIDI | MIDI Time Code - systems common message sending Hour Min Sec Frames information via MIDI protocol. |
| multiscan | Computer | A VDU or monitor that can handle a range of frame or refresh rates. |
| Multitimbral | MIDI | Electronic instrument capable of playing different sounds simultaneously, each sound responding to a particular MIDI channel |
| Mumetal | nickel alloy, 17%iron, 5% copper and 2% chromium by weight. Has high magnetic permeability and is used esp. in transformer cores and magnetic shields. |