.sd2
An extension given to ProTools SoundDesigner II files. This file extension covers several sample rates. Sd2 files are stand-alone files that have no header.
.snd
An extension given to many types of PC sound files. This generic file extension covers a variety of encoding formats and sampling rates. Snd files usually do not have a header that summarizes the information which Vox Studio needs.
.vap
An extension given to indexed voice processing telephony files. Vap files contain several concatenated ADPCM recordings and accompanying annotation text.
.vce
An extension given to NMS voice processing telephony files. This file extension covers a variety of encoding formats. Vce files are stand-alone files. They can be grouped into indexed files which usually carry the .vox extension.
.vox
An extension given to many types of voice processing telephony files. This file extension covers a variety of encoding and sampling rate formats. For example, Dialogic ".vox" files are stand-alone files and lack a header identifying the coding format and sample rate, but NMS ".vox" files actually are indexed files that contain many voice prompts and do have a header. We are sorry if this is confusing, but we did not create this mess.
.vsn
An extension given to many types of voice processing telephony files from several suppliers. This generic file extension covers a variety of encoding formats and sampling rates. Vsn files do have a header which summarizes most (but not all) of the information which Vox Studio needs.
.wav
An extension given to multimedia sound files recorded in Microsoft's standard waveform file format. This file extension covers a variety of encoding and sampling rate formats. Wav files contain a header identifying the coding format, resolution and sample rate. Wav files are to sound what Tiff files are to images.
AC
Alternating current.
ADPCM
Adaptive differential pulse code modulation. A speech encoding method based on storing only the difference between consecutive speech samples.
A-law
The PCM companding standard used in Europe.
Algorithm
Series of well-defined steps or computer instructions to process a signal
Aliasing
A problem causing spurious components in the signal. It occurs when a signal is sampled at a rate lower than twice the highest frequency present in the signal. This results in artifacts at a frequency which is the difference between these highest frequencies and half of the sample rate.
AM
Amplitude modulation. The encoding of information by varying a carrier signal's amplitude.
Amplitude
Distance between high and low points of a signal wave. There is a direct relationship between waveform amplitude and perceived sound volume.
ASCII
American standard code for information interchange.
Audio
Signals composed of frequencies detected by the human ear, i.e. between 20 Hz and 18,000 Hz. Audio signals transmitted over the telephone network only contain frequencies from 300 to about 3400 Hz.
Audiotex
Voice response service. Dial a number, hear the weather forecast.
Batch
Method whereby many files are processed automatically, one by one, without operator intervention
Belgium
A tiny humid kingdom of 10 million inhabitants. Belgium is bordered by France, the North Sea, The Netherlands, Germany and Luxembourg. Renowned for its dark chocolate, delicate lace, hot waffles, specialty beers, good food and Vox Studio. Xentec is located in an outer suburb of Brussels, the capital of Belgium and nerve center of the European Union.
Bicom
US provider of components and tools to assemble computer telephony systems.
CCITT
Comité Consultatif International de Télégraphie et Téléphonie. Based in Geneva, Switzerland, this permanent consultative committee of the International Telecommunications Union (ITU) elaborates and publishes a variety of international telecommunications standards.
Centigram
US provider of computer telephony systems.
Compand
COMpress/exPAND, a technique to reduce the dynamic range of a signal and then restore it to (close to) its original form.
CPU
Central processing unit. The brainy part of your PC.
Creative Labs
A provider of multimedia and telephony components. Also known as Creative Technology.
Creative Technology
A provider of multimedia and telephony components. Also known as Creative Labs.
CTI
Computer-Telephony Integration. A fashionable term for what, not so long ago, used to be called simply "voice processing". CTI has become a generic term for computer-controlled or computer-assisted telephony applications.
CVSD
Continuously Variable Slope Delta modulation. A time-tested coding technique that allows representation of analog signals with less digital information than pure analog to digital conversion.
dB
Decibel. Logarithmic representation of the amplitude of a signal. One decibel is the smallest change in sound volume that the human ear can distinguish.
DC
Direct current.
Decibel
dB. Logarithmic representation of the amplitude of a signal. One decibel is about the smallest change in sound volume that the human ear can distinguish.
Dialogic
US provider of components and tools to assemble computer telephony systems.
Distortion
Any spurious modification to a sound caused by the process that manipulates it or its digitized representation.
DTMF
Dual tone multi-frequency, also called "Touch-tone" by AT&T. 16 combinations of voice-band tones are used to generate dialing signals. The digits represented are 0-9, *, # and A-D. A-D are not available on standard telephones.
Elan Informatique
French provider of components and tools to assemble computer telephony systems.
filter
Manipulation that alters the spectral (frequency) components of a signal.
filtering
Process that alters the spectral (frequency) components of a signal.
FM
Frequency modulation. The encoding of information by varying a carrier signal's frequency.
FPU
Floating point unit. This arithmetic chip assists the CPU in doing fast calculations.
Frequency
The rate of vibration or oscillation of a signal as measured in hertz (Hz), or cycles per second. The normal human ear can detect sounds ranging from 20 Hz to 18,000 Hz. The telephone network only carries signals with frequencies between about 300 and 3400 Hz.
Group 2000
European provider of computer telephony systems.
header
A file header is a chunk of data at the beginning of a file where Vox Studio can find useful information such as recording sample rate, coding algorithm, recording length, and so on. Not all voice file formats have file headers. If Vox Studio has to open a file that has no header, it will ask the program user for the missing information it needs.
High-pass
Lets frequencies higher than the cut-off frequency through. Removes the frequencies below the cut-off frequency. There is always a finite slope around the cut-off frequency going from the untouched to the removed section.
Idle channel noise
Residual noise present when the voice signal has a zero amplitude.
Interactive Voice Response
IVR. Dial a number, hear information you select by pressing the keys on your telephone.
InterVoice
US provider of components and tools to assemble computer telephony systems.
IVR
Interactive voice response. Dial a number, hear information you select by pressing the keys on your telephone.
Leading
At the beginning of the sound file.
Linear
Used here with the meaning non-compressed and non-companded, straight representation of the original signal.
Low-pass
Lets frequencies lower than the cut-off frequency through. Removes the frequencies above the cut-off frequency. There is always a finite slope around the cut-off frequency going from the untouched to the removed section.
Microlog
US provider of computer telephony systems.
Milliseconds
Thousandths of a second.
Modulation
Variation of a wave to convey a signal or information.
Mu-law
The PCM companding standard used in the US and Japan.
Natural MicroSystems
US provider of components and tools to assemble computer telephony systems.
NewVoice
US provider of components and tools to assemble computer telephony systems.
Nibble
Four bits of binary information. Two nibbles can be stored in one byte.
NMS
Natural MicroSystems, US provider of components and tools to assemble voice processing systems.
Normalize
To make the volume of a recording as uniformly loud as possible while minimizing distortion of the sound. This is done in Vox Studio by normalizing average energy, not amplitude, of the signal.
Nortel
Canadian Telecom giant. Nortel also supplies Computer Telephony systems.
OKI
Provider of, amongst other things, silicon chips that convert an analogue signal into a variant of ADPCM. OKI chips were used on early Dialogic cards.
Pacific Image
Wrote the SuperVoice voice-mail application that comes with the PhoneBlaster card.
PCM
Pulse code modulation. Digital encoding method for sampled voice signals.
Pentium
A CPU chip used in PCs. Pentium is a trademark of Intel Corporation
Philips
Dutch Electronics giant. The Business Communication Systems Division also supplies Computer Telephony systems.
Phone banking
Dial a number, find out you are broke. One of the applications for Host Interactive Voice Response (HIVR). Similar to IVR but involves communication and exchange of data with a host mainframe.
RAM
Random access memory. The data your PC manipulates is retrieved from and stored in RAM. Your PC uses RAM chips.
Resolution
The resolution of a recording is indicated by the number of bits used to represent sample values. A 16-bit resolution gives a precision of about 0.003% of full scale. An 8-bit resolution gives a precision of only about 0.8% of full scale value. Use 16 bits if file size and conversion time is not a problem.
Rockwell
US provider, amongst other things, of silicon chips for modem and voice applications.
Sample rate
The frequency at which samples of sound are taken.
Sampling rate
The frequency at which samples of sound are taken.
SCII
French provider of components and tools to assemble computer telephony systems.
Signal-to-noise ratio
The ratio of the voice signal amplitude to the noise amplitude, usually expressed in dB.
SoundBlaster
A Multimedia sound card. SoundBlaster is a trademark of Creative Technology Ltd
SoundDesigner II
Popular Mac program from DigiDesign to produce and manipulate quality sound files.
Talking Technology
US provider of components and tools to assemble computer telephony systems.
Talk-off
Talk-off is a problem that occurs when a voice signal closely resembles a DTMF tone pair and activates erroneous detection of DTMF digits.
Threshold
Limit of amplitude or energy below which a signal causes no action or detection to take place
TouchTone
An alternative name for DTMF. TouchTone is trademark of AT&T in the US and is used by other companies in other territories.
Trailing
At the end of the sound file.
Voice mail
Analogous to Electronic Mail, except uses recorded voice messages instead of text messages. Can go from simple multi-user answering device functionality to complex office communication center functionality.
Voicetek
US provider of computer telephony systems, now part of Aspect Telecommunications.
Volume
Loudness of sound signal.
VU-meter
The good-old VU-meter, usually a needle instrument, measures speech power in decibels. 1 milliwatt is the reference. The Vox Studio monitor is not calibrated in decibels and serves essentially as a visual indicator for correct recording level.
Wave
The usual type name given to multimedia sound files recorded in Microsoft's standard waveform file format. This covers a variety of encoding and sampling rate formats. Wave files contain a header identifying the coding format, resolution and sample rate. Wave files usually have a ".wav" extension.
Windows
Windows is a trademark of Microsoft Corporation.