Stereo Subwoofer EQ Suggestions

[green heron]

I just built a stereo pair of sealed subwoofer boxes loaded with Aura 1808 woofers. I'd love to hear your suggestion for good EQ options? Here are my requirements:

* True stereo, not summed outputs (I know, most say bass is not directional below 100 Hz and most recordings are mono in that range anyway, but I want the flexibility to adjust each separately and keep the stereo, stereo)
* EQ range from 20 Hz to 100 Hz or slightly higher (if analog, I don't want EQ covering 20Hz to 20k Hz)
* I'd prefer an analog EQ for this simple task rather than going from D>A>D>A, but I'm open to DSP as long as it's self-contained or works on a Mac. I'll only use the DSP for the subwoofers, and don't need a crossover or other options, only EQ (I'm sure DEQX makes a nice unit, but it would be overkill just to EQ bass!).

Thanks!

[GM]

Maybe this?: Anti-Mode - VLSI Store

GM

[maxo]

Originally Posted by green heron

I just built a stereo pair of sealed subwoofer boxes loaded with Aura 1808 woofers. I'd love to hear your suggestion for good EQ options? Here are my requirements:

* True stereo, not summed outputs (I know, most say bass is not directional below 100 Hz and most recordings are mono in that range anyway, but I want the flexibility to adjust each separately and keep the stereo, stereo)
* EQ range from 20 Hz to 100 Hz or slightly higher (if analog, I don't want EQ covering 20Hz to 20k Hz)
* I'd prefer an analog EQ for this simple task rather than going from D>A>D>A, but I'm open to DSP as long as it's self-contained or works on a Mac. I'll only use the DSP for the subwoofers, and don't need a crossover or other options, only EQ (I'm sure DEQX makes a nice unit, but it would be overkill just to EQ bass!).

Thanks!

why you want to EQ your subs
also is not a good idea to tweak the sub at anytime
subs are set and forget specially on home enviroments
it is for your home setup ?
like for movies and or music ?

what you need to do is to sweep your room and look for modes
if you want to eq, i am pretty sure that you got some bad acoustics
the best way to deal with peaks and valleys on the sub audio spectrum
is with bass traps, the more controlled your room audio wise
the more tight and punchy you will hear your bass

also as you said, bass is non directional, you dont really want to have stereo subs, but you already built them, what you can do is to stack them side to side
to have more output out of them, instead of put them on left and right corners

with an ecm8000 and some free software you can sweep you room and graph
the freq response of it, the flatter the better but as i said, you need bass traps
to correct your peak and valleys,
you cant correct that with EQ, you will only overwork and damage your
sub drivers if you boost too much on the bands

There is plenty of info on the forums on what software they use to sweep a room
and how they do it
Max.

[green heron]

Thanks for the suggestion, GM...I'll look into the Anti-Mode. The Behringer DSP1124P looks like another option at a no-brainer price going for $50 on ebay.

[GM]

Yeah, it was very popular some years ago, but didn't mention it since I thought it was long out of production.

GM

[green heron]

Max - I'm positive that I have bad room acoustics. My system is in the basement, so I'm dealing with plywood over concrete walls and concrete subfloor. It's also an odd "L" shape. I think it's beyond what I could do with some bass traps. I've run sweeps and everything is really flat except for my subwoofer section—that's why I'm looking to EQ. Why do you say it's not a good idea to EQ subs?

[maxo]

Originally Posted by green heron

Max - I'm positive that I have bad room acoustics. My system is in the basement, so I'm dealing with plywood over concrete walls and concrete subfloor. It's also an odd "L" shape. I think it's beyond what I could do with some bass traps. I've run sweeps and everything is really flat except for my subwoofer section—that's why I'm looking to EQ. Why do you say it's not a good idea to EQ subs?

if you build your subs from a proven design around here
they must be pretty flat , unless you have changes some variable drastically
but if not, and your cabs are build within the specs
your problem is not to EQ your cabs but to tame the modes in your room

at what freq are you low passing your subs ?

[green heron]

GM - I emailed tech support for Anti-Mode and they said that the outputs are summed, so it looks like the Behringer (despite mixed opinions on the brand/company) is the better choice for my purpose.

[bentoronto]

Several difficult to address considerations. Might as well make life easier with a mixed bass signal to start with. Two subs (and with the same bass signal) is a very good idea - providing you are prepared to locate them in heterogeneous locations.

There is no way to separate speaker, location, and room... all the sound ends up with your listening position ears as the criterion. Far from flat and the bass of a room is not easy to control very much. I think, like concert halls, you should try to start with speakers and room that are pretty good (in dimensions and furnishings) and go from there. (I often howl with laughter seeing pictures of some bare-bones living rooms containing some state-of-the-DIY speaker systems which have to sound awful there.)

No way to diddle with all the peaks and valleys.

For my taste, nothing more intuitive than a parametric equalizer (or DSP equivalent) where you choose maybe two bad frequencies and then add or subtract and choose the width of the correction. (The outputs near the top and bottom of the sub range are handled in the pre-amp and cross-over stages.)

Anything more is just making yourself crazy.

Ben

[GM]

Originally Posted by green heron

GM - I emailed tech support for Anti-Mode and they said that the outputs are summed, so it looks like the Behringer (despite mixed opinions on the brand/company) is the better choice for my purpose.

??? Says it can do a pair of full range speakers.

GM