Acoustics Engineering - Technical Notes

Technical Notes

  • TN001 - Measuring Impulse Responses Using Dirac

    This is an introduction to using Dirac. The first part of this technical note introduces some of the theoretical background of Dirac. The second part illustrates the practical use of Dirac.

  • TN002 - Measuring Speech Intelligibility Using Dirac

    Starting from basic principles, this technical note introduces the parameters used in speech intelligibility measurements such as STI and RASTI. It also describes the hardware needed for successful measurements, calibration requirements and hints on how to handle common measurement situations.

  • TN003 - Using the Digital Input of the Digigram VXpocket

    The Digigram VXpocket is a high quality PCMCIA sound device, which gives excellent results when used with Dirac. Due to incompatibilities between the VXpocket driver software and Dirac, it is not possible to calibrate the digital input of the VXpocket. This technical note describes a procedure that will allow you to use the digital input as if it were calibrated.

  • TN004 - G From Imported Room Responses

    How to use Dirac to calculate the sound strength G from impulse responses that were not measured using Dirac.

  • TN005 - Practical Tips And Hints For Dirac

    This technical note intends to clarify where you should pay special attention before and during a measurement session, what problems may occur and how you can avoid or solve these.

  • TN006 - Insulation Measurements Using Dirac

    Methods are described to measure the airborne sound insulation, e.g. between two rooms. Dirac is used to measure the relative sound levels as well as the reverberation time.

  • TN007 - Impulse To Noise Ratio INR

    Describes the INR parameter, which represents the decay range of an impulse response. The INR can be used to qualify acoustical impulse response measurements.

  • TN008 - Dirac Stimuli

    The Dirac product CD contains a number of sound files that can be used as external stimuli in asynchronous (open-loop) measurements. This technical note describes these files and their use.

  • TN009 - Terratec DMX6FireUSB

    Installation, setup and calibration with Dirac. This USB sound device supports a sample rate of 192 kHz, and can be used for scale model measurements.

  • TN010 - E-MU 0202 USB

    Installation, setup and calibration with Dirac. This USB sound device supports a sample rate of 192 kHz, and can be used for scale model measurements.

  • TN011 - Using the B&K Type 2250 with Dirac

    The B&K Type 2250 Hand-held Analyzer can be used as a front end for Dirac. This document describes how to connect and set-up the 2250.

  • TN012 - Using Dirac for CEN 1793-5 measurements

    The latest update to 1793-5 requires the use of a 9-microphone array and modified calculations. This technical note describes the use of Dirac for this type of measurement. For more information, see the blog entry CEN 1793-5 Update