Third-Octave Export - RTA Measurement

Hi! Hope you're doing well.

I made some measurements using an RTA, and I need to represent them in octave bands or third-octave bands, using IEC 61260 center frequencies.

I didn't find a direct way to do this in REW. The closest approach was selecting 3 PPO with custom smoothing of 1/1 octave (see image attached).
I compared this export with another configuration: 48 PPO and 1/24 octave smoothing. I plotted these two bar graphs to check if there was a good correlation (see image attached).

However, I'm still not sure if the first option is correct, because I don't know how REW is averaging or integrating the values.

If any of you have encountered this issue before and have a recommendation, I would really appreciate it.

That's tricky with an individual measurement you have already made. If you use the REW RTA to capture data you can select the option to use bars and select the octave fractions you are interested in from the RTA, saving as a measurement each time. The octave fraction can be changed at will in the RTA after you have acquired the data and REW will recalculate the results as required from the underlying spectrum data. You could then export those measurements without any smoothing at the required spacing.

John Mulcahy said:

That's tricky with an individual measurement you have already made. If you use the REW RTA to capture data you can select the option to use bars and select the octave fractions you are interested in from the RTA, saving as a measurement each time. The octave fraction can be changed at will in the RTA after you have acquired the data and REW will recalculate the results as required from the underlying spectrum data. You could then export those measurements without any smoothing at the required spacing.

Click to expand...

Thanks, John, for the quick response!

Yes, in this case the measurements are already done. I tried to convert them into octave-band bars in REW, but it wasn't possible. Now I'm working on a script to do it.

Maybe exporting SPL in octave or third-octave bands could be a really useful update for REW!