User Manual

Yamaha Sound System Simulator Y-S
3
Owner’s Manual V3.1
60
10. General Theory
General calculation methods
• Y-S
3
computes the speaker array response at the receiving point or audience area.
• The responses are computed by combining the responses from each speaker based on a geometrical simulation.
• Each speaker response is computed using measured directional impulse responses. First by selecting the impulse
response for the corresponding direction based on the relationship between the receiver point and the speaker
position, and then considering the effects of attenuation by distance, air absorption, amplifier type, system
attenuation, and processor settings (EQ, delay).
• There are two methods of combining responses: a method that considers the interference and a method that is
based on the summing of energy and not taking the interference into account.
• The response is limited to direct sound. Calculations are performed as for a free sound field without any
reflections.
• The sound pressure level is calculated assuming sine wave or pink noise input to the system.
• There are two types of pink noise: band-pass filtered noise for the “Swept Band Noise” option or overall noise for
the “Full Band Noise” option.
• The response for the two channels used in auralization is computed by first convolving the head-related transfer
function (HRTF) of the directions corresponding to each speaker’s response, and then combining these
responses.
Auto setting methods
• There are two auto setting functions. “Auto layout” selects the appropriate speakers for the current room
configuration, and “Auto tuning” determines the parameters (Angle, EQ, Amp type, Input Level and Attenuation)
for each speaker.
• The results for each function are only rough estimates, and adjustments or modifications will be necessary for
either method. Calculations are made based on the following theory.
1. Auto layout
• Y-S
3
selects the speaker type that is appropriate for the configuration of the room, its area, and the dimensions
of the floor.
• Speaker positioning is conducted in accordance with the speaker arrangement methods (Center, Center + Side,
Side) while considering the ceiling height of the room.
• Angles are set to default: Pan and Rot = 0 degrees, Tilt = 30 degrees and Splay Angle = minimum.
2. Auto tuning
• Y-S
3
sets speaker parameters for each speaker array.
• Y-S
3
decides the speaker angles (Pan, Tilt and Splay Angle) to minimize the standard deviation of the sound
pressure level within the area that is selected by the user as the coverage of the speaker array.
• When computing angles, the proper setting is selected from among the conditions in which all of the target points
of the speaker composing the speaker array are within the selected cover area.
• Y-S3 decides the EQ and gain for each speaker so that the frequency responses are flat and their levels match the
required SPL set by the user at the target points of each speaker that composes the speaker array. (Note 1: In auto