Lab2

Analysis of Voice Quality – Inverse filtering and LTAS (Long Time Average Spectrum)

Material

Use recordings made by the legendary wonderful phonetician Gösta Bruce of different voice qualities.

The recordings can be found here (are the audio files).

Record the same voice qualities with your own voice only uttering /a:/ for a few seconds. Use your own recordings for the analyses and use Gösta's as references.

Read pages 68-79 in Johnson (3rd edition), short text on Labelling voice qualities and a short paper on LTAS.

You also need to start reading pages 1-16 in Eva Björkner's thesis which is downloadable.

A good idea is to first read the instructions (for the whole practical).

Inverse Filtering

Read 1 and 2 in the tutorial from the Praat website here

LTAS

Create an LTAS object after you have inverse filtered each recording. You do that by selecting your inverse filtered Sound object and the choose "Analyse spectrum" -> To Ltas... Choose a bin width of 100 Hz.

Draw the resulting LTAS object, remember to use the same dB-scale for later comparison between recordings. Paste the resulting picture in your report.

Report

Compare the different LTAS objects and reflect on the differences. What is expected and what was your outcome?

Send the report to your teacher including pictures and reflections. Hopefully the literature has been useful and you can refer to it in your report.