[Wayne A. Pflughaupt]

Nordo wrote:

The reason I started to look at EQing the subs is because one of my sub drivers is bottoming during heavy passages.

I’ll bet one of them measures not as loud as the other with the SPL meter, so you’ve turned it up to compensate? I had the same problem when I tried separate placement of my subs, because one location was very inadequate.

As brucek has noted on other threads, the main reason to go with separated subs is if it gets you a favorable response curve that you aren’t able to achieve from a single location. There can be other reasons to separate them – perhaps blaser can give his – but typically if you do, it only works well in or near the corners of a perfectly symmetrical room – one with “shoebox” dimensions, for example.

So I am hoping to incorporate a subsonic filter in my EQing with the BFD. Is this possible?

The BFD doesn’t have a subsonic filter. People have accomplished “creating” a low pass filter by stacking multiple filters, effectively the same thing as what you’re wanting, although a high pass (aka subsonic) is more problematic. I modeled a crude one in REW using several filters, shown in this graph:

BFD high pass.JPG

As you can see, the best you can do is attenuate the lows only to a certain level, not an infinite slope like you’d have with a real high pass. Still, it might be enough to do the trick for you. Eliminating the last filter (#9) and tweaking the others would move the cut-off point up to ~25 Hz. It wouldn’t be hard to move the cut-off up higher, if you needed to.

The caveat is that you’ll only be left with a single channel to do your subwoofer equalizing, so if you want to EQ your subs separately and create a high-pass for one, you might need a second BFD.

Overall, unless you have a compelling reason to keep them separated, I’d put the subs together and EQ as one.

When you re-do your graphs to the correct scale as brucek suggested, I’d like to see one with combined response as well as the two separately

Wayne
Can you change the thread topic as blaser suggests?

Done.

Regards,
Wayne