This page explains how to operate in Revit based on the contents of 1 and 2.
On this page, the equal sound pressure surface is expressed as a "balloon."

First, install and select your ceiling speakers. Check "1kHz" in the properties. Then, a 1kHz balloon will be displayed around the ceiling speaker. Balloon is available in 1kHz and 4kHz. Generally, 1kHz is the main frequency of the voice and is designed to have a high sound pressure. Therefore, it is used to check the maximum allowable volume. 4kHz can be used to check voice intelligibility.
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Now enter the maximum allowable sound pressure in [Desired SPL]. Here, it is assumed to be 95dBspl. Click [Apply] to make the balloon smaller. This means that the sound pressure on the surface of this balloon is 95dBspl. The sound pressure inside is much higher. In other words, this is a very noisy situation for this person. He will probably complain to the facility manager. Or he may never visit here again.
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Enter a negative value for [Attenuation] so that the [95dBspl] balloon is above this person's ear level. Of course, each person's height is different, so it doesn't have to be a precise adjustment. In this explanation, -6dB is input. This operation is equivalent to turning the AMP or attenuator knob to lower the volume by 6dB. And this person will never be exposed to loud noises greater than 95 dBspl, which is currently assumed to be the maximum allowable level.

​Next, check the range of sound pressure that you want to ensure as a minimum.​

Here, decide the minimum sound pressure you want to secure. In this tutorial we will use 80dBspl. Strictly speaking, it would be sufficient to secure a sound pressure that is 6 to 10 dB higher than the expected draft noise. Enter 80 in [Desired SPL]. Then, a large balloon will appear. The range indicated by this balloon is the range where 75dBspl can be secured.

With this, we have created a balloon that secures a minimum sound pressure of 75 dBspl and encloses a space where the people inside are not exposed to a maximum allowable sound pressure of 95 dB or more.

​Next, place multiple speakers on the ceiling.

It will be displayed on the floor plan as shown on the right.

Copy the ceiling speakers and place the speakers so that the balloons touch each other at listener ear level.

Refer to the overlap between the two balloon circles in the upper picture and arrange the speakers. However, in actual acoustics, building structures and building materials produce reverberations, which greatly affect the sound pressure level. Therefore, there is no need to perform strict placement during confirmation work at this stage.