Originally Posted by DarkEnigma
I recently decided to experiment with REW a little bit, since on a small
number of songs I would notice that the bass seemed to drop in and out quite a bit. Most of my music sounds fine to my ears but I figured I should familiarize myself with the program since I plan on adding a second sub for headroom and hopefully an improved response.
I'm using the BAFX advanced sound meter on the C weighting to take my measurements and not a UMIK-1.
When outputting 75db Pink noise from REW the SPL meter read ~73-75 db. I measured a 20hz sine wave at my MLP and the SPL meter read 79db while REW was outputting 86db. The two measurements got closer as I went up in frequency, so I presumed REW was applying the C weighted correction factors properly before taking these tests. I tested the sub with my mains (fr, fr and CC) in the 16hz and 20hz tuning about 12' away at my MLP. All the graphs per tuning looked pretty much the same so i just averaged them and put a 1/12th smoothing on.
The sub is a PB12-plus in a completely untreated room, around 5,500ft^3 with tiled floors over concrete (a basement). The crossover is at 80hz. Is there anything wrong with this graph that I should be specifically looking to fix or is this fairly normal for an untreated room?
From my understanding, there is a lot of room for improvement but I thought I'd leverage the expertise on this site.
If something seems off about the graphs, what can I do to improve it?
I don't think you can put too much value into those measurements just glancing at the specs of your SPL meter I would say it accuracy is pretty questionable especially in the lower frequencies. The PB12 should not be dropping off that fast at 40hz so it is either the meter or something else is going on. I would guess the meter is not accurate down that low and needs a calibration/correction file.
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