Latest REW graphs of my budget sub...

[blazerman]

Here are the latest graphs form my sub and mains. Got some early troubleshooting with my BFD, but finally got the groove of it. Assuming my midi interface is working fine, the BFD seems to have the v1.3 chip (can't load filters using REW). Anyways, it was fun to figure out how to program the filters manually.

My sub is very subpar compared to most subs in these forums, so keep that in mind as it rapidly rolls down around 27 hz (you get what you paid for! ). Used DVE for initial level cal, ECM8K, RS analog for SPL reference, and a calculated target level of 72.5 db (75 was too much for my neighbors), 1/6 and 1/3 smoothing, xo = 80 (receiver). I tried 13 different positions around the room, and these are the best results.

Sub alone, No EQ:
sub_hts.jpg

I guess a lot of the booming I've been experiencing in movies is related to that huge lift around 48 Hz.

Here's the Sub + Mains, No EQ:
sub_mains_hts.jpg

After applying the REW initial filters and playing around with them...

Sub alone, with BFD EQ:
sub_bfd_hts.jpg

And with the mains it actually improved some...
sub_mains_bfd_hts.jpg

Any suggestions are more than welcome. Overall sounds more uniform, but it lost some punch on movies. Tested with SW Episode 3 (opening battle, and climax on the volcanic planet), and T2 Sp Ed (openning scene). Lows seem better defined now, and the transition from mains to sub feels smoother too . Next post shows a quick reflection hunting and correction.

[blazerman]

Also generated some impulse plots and actually found a couple of (potentially significant) reflections from both mains.

Both mains:
mains_imp_hts.jpg

From John M's reasoning in a different thread, the two main signals around zero ms should represent the first impulse of each speaker, the first peak corresponding to the left speaker which is slightly closer to the listening area. Then a second pair of peaks are shown between 4.7-5.2 ms.

After scratching my head for hours trying to find the culprit, finally found the source. The backwall spot just between the rear surround speakers, which nicely corresponds to approx. 4'9", and 5'5" feet of extra travel path from each speaker to the microphone.

This is the same plot after placing a small curtain in the spot between the rears.
mains_imp_treat_hts.jpg

Seems it took care of it.

Well, there it is. I guess I'll take a break after 3 days of heavy measuring , and enjoy some tunes and movies. Thanks to all the great people in these forums for their great support.

Suggestions, comments????

Blazerman
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Hearing is Believing!

[blazerman]

Well, no reply so far means one of two things: either my graphs look too good...or they are sooo bad. I will resume measurements this week and before doing major changes would like to hear some suggestions.

Blazerman

[pinduro]

Hi Blazerman,

Great to see your example before and after, both f. response and impulses...I'm sure you had a fun 3 days..;-)

More uniformity in the sub region, for sure (a good thing)...but you mentioned it might've lost a bit of impact...perhaps you might try a house curve to spice things up?

Good luck,
Mike