Pan law
Encyclopedia
Pan law, or pan rule, is a recording
and mixing
principle that states that any signal of equal amplitude
and phase
that is played in both channels of a stereo system will increase in loudness
up to 6.02 dBSPL, provided there is perfect response in the loudspeaker system and perfect acoustics
in the room.
Often, the acoustic summing of a room and system are much inferior to the ideal, so the specific relative level will change from −3 dB to 0 dB as the mono signal is panned
from center
to hard left or right, and this sounds natural. The idea is that when one directs signals left and right with the pan pot
, the perceived loudness will stay the same, regardless of latitude.
However, both the direction of attenuation
throughout the panoramic sweep and the amount by which the signal is attenuated vary according to pan rule. For example, the Yamaha digital consoles employ a typical (compromise) 3 dB pan rule, however, the signal is at full level at 12:00 and becomes progressively louder (up to + 3 dB) as it is panned to the right or left.
The 3 dB pan rule is a commonly applied compromise to comply with the mediocre acoustic summing capabilities of most control rooms. However, the console manufacturer
SSL used to employ a 4.5 dB pan rule, because it was believed that their expensive consoles would normally be used in tuned rooms that had acoustic summing capabilities closer to the ideal.
Many consoles that have only one pan rule employ one such that a signal panned hard left or right is at full level and becomes progressively lower in level as the pan is directed to the center.
According to mastering engineer Glenn Meadows, the Kinoshita-Hidley rooms at Masterfonics (Nashville, Tennessee
), produce close to 5.9 dB acoustic summing when both loudspeakers are presented with the same in-phase signal.
Recording
Recording is the process of capturing data or translating information to a recording format stored on some storage medium, which is often referred to as a record or, if an auditory medium, a recording....
and mixing
Mixing console
In professional audio, a mixing console, or audio mixer, also called a sound board, mixing desk, or mixer is an electronic device for combining , routing, and changing the level, timbre and/or dynamics of audio signals. A mixer can mix analog or digital signals, depending on the type of mixer...
principle that states that any signal of equal amplitude
Amplitude
Amplitude is the magnitude of change in the oscillating variable with each oscillation within an oscillating system. For example, sound waves in air are oscillations in atmospheric pressure and their amplitudes are proportional to the change in pressure during one oscillation...
and phase
Phase (waves)
Phase in waves is the fraction of a wave cycle which has elapsed relative to an arbitrary point.-Formula:The phase of an oscillation or wave refers to a sinusoidal function such as the following:...
that is played in both channels of a stereo system will increase in loudness
Loudness
Loudness is the quality of a sound that is primarily a psychological correlate of physical strength . More formally, it is defined as "that attribute of auditory sensation in terms of which sounds can be ordered on a scale extending from quiet to loud."Loudness, a subjective measure, is often...
up to 6.02 dBSPL, provided there is perfect response in the loudspeaker system and perfect acoustics
Acoustics
Acoustics is the interdisciplinary science that deals with the study of all mechanical waves in gases, liquids, and solids including vibration, sound, ultrasound and infrasound. A scientist who works in the field of acoustics is an acoustician while someone working in the field of acoustics...
in the room.
Often, the acoustic summing of a room and system are much inferior to the ideal, so the specific relative level will change from −3 dB to 0 dB as the mono signal is panned
Panning (audio)
Panning is the spread of a sound signal into a new stereo or multi-channel sound field. A typical physical recording console pan control is a knob with a pointer which can be placed from the 8 o'clock dial position fully left to the 4 o'clock position fully right...
from center
Center channel
Center channel refers to an audio channel common to many surround sound formats. It is the channel that is mostly, or fully, dedicated to the reproduction of the dialogue of an audiovisual program...
to hard left or right, and this sounds natural. The idea is that when one directs signals left and right with the pan pot
Panning (audio)
Panning is the spread of a sound signal into a new stereo or multi-channel sound field. A typical physical recording console pan control is a knob with a pointer which can be placed from the 8 o'clock dial position fully left to the 4 o'clock position fully right...
, the perceived loudness will stay the same, regardless of latitude.
However, both the direction of attenuation
Attenuation
In physics, attenuation is the gradual loss in intensity of any kind of flux through a medium. For instance, sunlight is attenuated by dark glasses, X-rays are attenuated by lead, and light and sound are attenuated by water.In electrical engineering and telecommunications, attenuation affects the...
throughout the panoramic sweep and the amount by which the signal is attenuated vary according to pan rule. For example, the Yamaha digital consoles employ a typical (compromise) 3 dB pan rule, however, the signal is at full level at 12:00 and becomes progressively louder (up to + 3 dB) as it is panned to the right or left.
The 3 dB pan rule is a commonly applied compromise to comply with the mediocre acoustic summing capabilities of most control rooms. However, the console manufacturer
Console manufacturer
A console manufacturer is a company that manufactures and distributes video game consoles. It is also known as a first-party video game publisher...
SSL used to employ a 4.5 dB pan rule, because it was believed that their expensive consoles would normally be used in tuned rooms that had acoustic summing capabilities closer to the ideal.
Many consoles that have only one pan rule employ one such that a signal panned hard left or right is at full level and becomes progressively lower in level as the pan is directed to the center.
According to mastering engineer Glenn Meadows, the Kinoshita-Hidley rooms at Masterfonics (Nashville, Tennessee
Tennessee
Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...
), produce close to 5.9 dB acoustic summing when both loudspeakers are presented with the same in-phase signal.