Public address system (PA)

Oltage voltage

Amplifier

Speaker, speaker

Ceiling Speaker

Aux. = auxiliary

Aux.send assisted delivery

Clip clipping

Direct (output) Jack

Fader attenuator, pusher

Flowback

Group group

Ins. = insert, also known as out and in

LF = low mid frequency

Limit limit

Line input socket

Mainsum mixed mono

Master master

Meterasign header setting

MF = mid frequency

MHF = mid high frequency

frequency response

Directivity

CD

CD is the abbreviation of compact disc: usually refers to a small digital audio record system that uses laser to pick up sound signals

CD -- ROM

CD -- V disc

Cd-v disc

In addition to recording the same audio signal as CD, there is also 5min image signal.

Is an interactive or CD-ROM, or dialogue CD-ROM. The information recorded on the CD can be exchanged with users.

CD -- R CD

It is a one-time recording disc, also known as additional recording disc, which is a blank disc provided to users. Users can use CD to record audio-visual or graphic information. After one-time recording, they can't erase it as a permanent record.

It is a kind of magnetic disc, which can record and play repeatedly. The straight longitude is 64mm. When recording, add a magnetic field above and a laser beam below. There are information reading windows at the top and bottom.

MPEG

Digital sound and image compression coding technology.

It is an important parameter to measure the quality of ten thousand tones. Its length has a great influence on the auditorium listening. It is defined as: stop making sound after reaching the steady-state sound field. The sound attenuation is 60dB. The time experienced is recorded as (60) in seconds.

Maximum pressure level

It refers to the highest steady-state quasi peak sound pressure level produced by the sound reinforcement system at the auditorium. The so-called quasi peak sound pressure level is the sound pressure level expressed by the effective value of the steady-state simple harmonic signal sound pressure with the same peak value for the non harmonic waveform sound.

Transmission frequency characteristics

In the hall, the amplification system will generate the gain when the critical gain of per unit feedback self excitation minus 6dB.

Transmission gain

It is the difference of steady-state sound pressure level at each auditorium when there is sound reinforcement in the auditorium.

Haas effect

The listener only pays attention to the direction of the first arriving sound and ignores the direction of the successive short delay sound, that is, the sound arriving within 30ms will mix with the first sound, which is called "Haas effect"