Originally Posted by Pres2play
I placed the second sub beside the front right speaker, a 1/4 distance from the sidewall. The response is better.
First of all, the response represented by the green line is significantly better than the one represented by the red line--congratulations for that! And the waterfall graphs at 300ms look pretty good. Having said that, I would like to make several recommendations with regards to the presentation of the measurements, and the results:
- Always present both a "before" and "after" graph that isolates only the change you are measuring. For example, you show Red as the "Before" measurement, with no correction, and the Green "after" graph with correction. To assess the benefit of moving the sub into the 1/4 position, your "after" graph should be without correction as well. Otherwise, how can we as observers tell whether the improvement is the new location, or simply the correction?
- It is a good idea to enter a description for each measurement so you, and we as the interested observers, can tell what was measured. "May 13 at 14:47" won't allow you to remember what was measured if you return to these measurements later.
- I agree with Markus' comment--low frequency measurements should always be presented with no smoothing. I recommend presenting two graphs, 15-300Hz with no smoothing, and 15-20,000Hz with 1/6 smoothing (same measurement, just different presentation).
- I also agree with Markus regarding the narrow ringing at 60Hz. This is likely to be caused by electrical noise somewhere in your system. You should experiment with grounding your components.
So, returning to the Green measurement, where are the two subs positioned for this measurement? Are they both on the front wall at 1/4 and 3/4 points, or is the second sub somewhere else? Sorry for all the suggestions, but you are the only thread participant who is making and posting measurements right now.