Aurora for Audacity

Hello,
Thank you for your great tool. I use Aurora for Audacity and have measured room impulse responses with a dodecahedron and omnidirectional microphone. To do this I created a sweep and inverse filter and then I used the inverse filter to drop the impulse response. Do I have to cut out distortion products in Audacity? I also want to evaluate the Strength G, but Aurora Acoustical Parameters shows values of -100 dB. Which I think is unrealistic, as the room is very reflective I would have expected +30 dB or more. Do I have to read in the sine sweep for the correct calculation? Or how do I proceed?
Many thanks for your help in advance
Dominik

The version of Aurora for Audacity does not contain the Impulse Response Select module. So yes, you need to manually cut the results, insulating just the latest IR (linear) or the previous ones (harmonic order distortions).

Strength G; instead, can be correctly calculated in two ways.

1) the general good one, which I always recommend. Emit pink noise from your dodecahedron, having locked the gain to a precise calibrated value.
Measure its power level Lw in octave bands (either using ISO-3744 or ISO 9614 standards).
Then place the dodecahedron on stage in the theater, go with your sound level meter at the listening position, and measure the octave band SPL values while playing the very same calibrated pink noise.
Once you know the value of Lw in each band and the vlue the meaured ZPL in the each band, you can compute Strength G in each band as
G = SPL - Lw + 31 dB

2) the crap, approximate way from the impulse response. This is affected by an error of 2-4 dB, hence it is not recommended. However this can be done as "plan B" when method 1) was unfeasible. In this method, you still first to calibrate your sound source performing a fully anechoic impulse response measurement, with the microphone at a known distance from the source (say 3m), and keeping the gain locked at the very same value which later will be used in the theater. Also the rescaling gain applied during the convolution with the inverse sweep must be locked to a given value, which later must also be employed when processing the measurement in the theater.
You first open the anechoic IR, perform an Acoustic Parameters evaluation. At this point you press on the button labelled "Store G Reference Signal". You will be asked for the source-microphone distance, and the current values of G will be stored as reference.
After this, you open the IR measured in the theater, perform the Acoustical Parameter evaluation, and now the values of G should be "correct". But remember, this procedure is strongly approximate. Procedure 1) is way more reliable and preferable