Glossary, Audio Sources/Source devices

GLOSSARY

Audio Sources/Source devices

These are the components of your HiFi system and all other appliances, whose sound you want to hear over the system and are thus connected to the pre- amplifier, amplifier or receiver. This includes CD players, DVD players, tuners (radios), cassette play- ers, DAT recorders, personal computers, record players, portable audio devices and many more.

Bi-amping

For this setup of your system, suitable loudspeakers are connected via two separate loudspeaker cables each to two amplifiers or main amplifiers. One cable is provided for the loudspeaker connection supplied with the higher frequencies, the other with the one for the lower frequencies. One amplifier or main amplifier is responsible for the supply of the higher frequency range of both loudspeaker’s input and the second device is responsible for the low fre- quency range of both loudspeaker’s input. The filte- ring of the entire frequency range takes place in the circuitry of the loudspeakers. For this operation mode you need double the number of main ampli- fier channels (usually double the number of main amplifiers) and double the cabling. The gain in sound quality in Bi-amping mode is for many com- binations of loudspeakers and amplifiers considera- bly higher than with Bi-wiring. Here too the metal bridges attached to the double connectors of the loudspeaker in normal operation must be removed.

Bi-wiring

Here suitable loudspeakers are connected via two separate loudspeaker cables each, every speaker to two output clamps of an amplifier or main ampli- fier. The filtering of the entire frequency range takes place in the circuitry of the loudspeakers. One cable is connected to the loudspeaker connector provided for the higher frequencies and the other to that provided for the lower frequencies. This dou- bles the cabling, but for many combinations of loud- speaker and amplifier this does improve the sound quality. Before reconfiguring to Bi-wiring, the metal bridges attached to the double connector of the loudspeaker in normal operation must be removed.

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Input sensitivity

Term for the smallest average (RMS) input voltage which causes the maximum output power at the maximum volume setting on the amplifier. Examples: 100 mV to 500 mV (Millivolts) on high level inputs, 2 mV to 5 mV on the phono MM input or 0.1 mV to 0.5 mV on the phono MC input.

MP3

MP3 (MPEG-1 Layer 3) is a compression procedure and an audio file format. It was developed together with procedures for the data compression of video signals in the MPEG-1 standard but it is also used independently. The files are recognised by their file name extension “.mp3”. Digital raw data (for ex- ample from an audio CD) are processed in such a way that the volume of data is greatly reduced. In this process the signal is almost inaudibly corrup- ted, so that the procedure results in irreversable quality loss. There are various possible properties for audio data within this format: mono or stereo, different sampling rates, different bit rate (e.g. 16- bit) and different levels of compression, defined by the transfer rate (very often 128 kbit/s (kbps)). On playback an audio signal close to the original is reproduced.

dB-Level

This is a way of describing any physical quantity; it is a common measurement for signal voltages and the volume. It is given in decibels (dB). Alternating signal voltages below 1V (RMS) are described as “line level” voltages, which are suitable as music signals for amplifier inputs. Inputs on amplifiers (mostly represented by RCA sockets), which are designed for signals on the CD player, tape recor- der, DVD player etc. are also referred to as “line level inputs” or “high-level inputs”. Those signal inputs must not be confused with inputs that accept preamplified signals.

RCA

RCA is the American name for a type of coaxial connectors and sockets, originally the abbreviation for “Radio Corporation of America”, the name of a

United States company. Both the plug and cable consist of a rod-shaped inner lead and a cylindri- cal-shaped outer lead. This enables a mono audio signal or a video signal to be transmitted. Compared to the XLR plug connector, this type of connection is also called “unbalanced signal con- nection”.

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