Typical measurement setup to cover your requirements for measuring and analysing architectural and building acoustics.
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Background
To investigate the acoustical properties of a room, you can clap your hands and listen to the response
of the room. Although it may not be easy to describe accurately what you hear, this method evidently
gives you an impression of whether music would sound pleasant or speech would be intelligible in this room.
Impulse Responses
The mathematical impulse or Dirac delta function, named after the theoretical physicist
Paul A.M. Dirac, is infinitely short and has unit energy. A system’s response to such an
impulse contains all the information on the system, and as such, is convenient for
analyis and storage.
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Required Hardware
The minimum hardware required is a PC with a soundcard, an impulsive
sound source, such as a blank pistol, and a microphone connected to the actual soundcard
line input. Each of these three components can be varied, depending on the type
of measurement to be performed.
Typical soundcard functions are a line input, a line output and gain
controls. In case of a notebook or laptop PC, soundcard functions are integrated or
otherwise can be attached as a PCMCIA or USB device.
Instead of an impulsive sound source, you can use a loudspeaker
sound source. To measure room acoustical parameters in compliance with the ISO 3382
standard, an omni-directional sound source should be used. To simulate a real talker
in speech intelligibility measurements according to the IEC 60268-16 standard, you can
use a mouth simulator or a small loudspeaker. To measure the speech intelligibility
through a sound reinforcement system, you can use the loudspeakers of that system.
At high sound–pressure levels, the signal from the microphone may be sufficient to
perform impulse response measurements, when fed directly into the soundcard line
input. However, additional amplification is usually required. In this instance, a sound
level meter with a line output could be used.
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Build a high quality measurement and recording microphone by Siegfried Linkwitz ( extern link )
Using the Panasonic WM61A as a Measurement Microphone ( extern link )
Recording and Measurement Microphones (Rod Elliott (ESP)) ( extern link )
The "Alice" Microphone ( extern link )
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Acoustical Measurement Basics
