Apollo Software Manual v7.0 - zZounds.com

FPGA Acronym for “Field Programmable Gate Array.” A type of integrated circuit that canbe programmed after manufacturing (“in the field”) to perform specialized functions.Front End Refers to a device that provides analog and digital input/output (I/O) to a digitalaudio workstation (DAW). Apollo is a front end.Graphical User Interface A software window, panel, or screen containing controls whereparameters are adjusted by the user. (See “GUI”)GUI Acronym for Graphical User Interface.Hi-Z Abbreviation for “High Impedance.” Apollo’s Hi-Z input allows direct connection ofan instrument such as electric guitar or bass via a standard unbalanced ¼” jack.High Resolution In digital audio, refers to 24-bit signals at sampling rates of 88.2 kHz orhigher.Hz Abbreviation for “Hertz,” a unit of measurement describing a single analog audiocycle (or digital sample) per second.Impedance A description of a circuit’s resistance to a signal, as measured in ohms, thousandsof ohms (Kilohms), or millions of ohms (megohms).Internal Clock A clock signal derived from onboard circuitry. (See “Clock”)I/O Acronym for “input/output.”kHz Abbreviation for “kiloHertz” (a thousand Hertz), a unit of measurement describing athousand analog audio cycles (or digital samples) per second. (See “Hz”)JFET Acronym for Junction Field Effect Transistor, a specific type of FET which has somesimilarities to traditional bipolar transistor designs that can make it more appropriate foruse in some audio circuit designs. (See “FET”)Jitter Refers to short-term variations in the edges of a clock signal, caused by a badsource clock, inferior cabling or improper cable termination, and/or signal-induced noise.A jittery signal will contain spurious tones at random, inharmonic frequencies. Usually,the jitter will be worse with higher signal frequencies. The internal digital clock ofApollo was designed for extreme stability and jitter-free operation, and its onboard phasealigned clock conditioner circuitry removes jitter from external sources, so conversionquality is uneffected by clock source.Lightpipe A digital connection made with optical cable. This was a phrase coined by Alesisto make a distinction between the proprietary 8-channel optical network used in theirADAT products and standard stereo optical connectors used on CD players and otherconsumer products.Line Level Refers to the voltages used by audio devices such as mixers, signal processors,tape recorders, and DAWs. Professional audio systems typically utilize line levelsignals of +4 dBm (which translates to 1.23 volts), while consumer and semiprofessionalaudio equipment typically utilize line level signals of -10 dBV (which translates to 0.316volts).Apollo Software Manual114Glossary