[SCOTI]

Originally Posted by TA_C10

And here is the result, the best I could get it. It dropped from -15 to -20 db almost. So the drone is still there, but quieter. I was expecting it to be completely cancelled. If you guys have any suggestions let me know.

I lengthened the pipe with my clamps, playing with several different configurations. I also shortened the pipe by turning the 2" capped end's 180 degree and putting them in the clamps backwards. But that shorted it probably down to like 25-28" and if you look at the spreadsheet, longer should have worked better than shorter. Nothing worked except the original 35" I originally built them to, which the Hz is still the same pretty much, but the db's went down.

I dunno.....

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This is exactly what I wondered. Would the ends justify the means? I guess even that (the answer) is subjective. Some might view reduction as a win. Others seeking complete cancellation probably wouldn't.

Are you happy w/it as-is or are you going to keep @ it?