Judth: We use the ETF software a calibrated microphone and pre-amp from Germany, and couple all of it through a PC computer. This provides the noise burst. The detector is at the listening position, but we generally vary it with about 6 sequential measurements to get some averaging (but do not actually use an averagin function as it can be misleading) It's pretty amazing the measurements we can achieve today with about 1/10 the cost of hardware required only 5 years ago. You can go to our website at see the software and measurement tools we use:
http://www.rivesaudio.com/software.html
The kits we sell here are primarily for our dealers that take measurements for us, but do still provide them to end users that feel they need this level of measurement for themselves.
The calculations are pretty basic if you are into room acoustics. Look at the impulse response and determine if it is being affected by the room and how much. If the impulse times match the distances for reflections, then it coincides with the room, if not, then you need to look elsewhere. The real issue becomes is there something different going on with the time energy curves (this can be viewed in the waterfall plots as well) in the frequency you are describing as a problem, vs the rest of the frequency spectrum. As Sherlock Holmes--I would look for these differences--in all areas of measurement (not just the ETC and waterfall) and then try to logically deduce why they exist and how they might effect the overall performance. I do agree with you--it is a Sherlock Holmes exercise, because you have to go after what you first suspect--it may lead you to nothing, in which case you have to look elsewhere--thus I have not provided a solution--just some areas to look into further.
http://www.rivesaudio.com/software.html
The kits we sell here are primarily for our dealers that take measurements for us, but do still provide them to end users that feel they need this level of measurement for themselves.
The calculations are pretty basic if you are into room acoustics. Look at the impulse response and determine if it is being affected by the room and how much. If the impulse times match the distances for reflections, then it coincides with the room, if not, then you need to look elsewhere. The real issue becomes is there something different going on with the time energy curves (this can be viewed in the waterfall plots as well) in the frequency you are describing as a problem, vs the rest of the frequency spectrum. As Sherlock Holmes--I would look for these differences--in all areas of measurement (not just the ETC and waterfall) and then try to logically deduce why they exist and how they might effect the overall performance. I do agree with you--it is a Sherlock Holmes exercise, because you have to go after what you first suspect--it may lead you to nothing, in which case you have to look elsewhere--thus I have not provided a solution--just some areas to look into further.