I'm reading a lot more into paired subs to level out peaks/dips and provide a more thorough coverage of my space, the only thing is I have one Klipsch RW-12d but at a MSRP of $700 I don't want to buy another. I'd rather be getting a HSU/SVS/etc. sub with similar performance at half the price but I'm worried about the differences between them.

Now I know that the timbre question is pretty much moot, but what I am concerned about is getting a sub with significantly better low frequency extension and having that characteristic localize the sub or create a sub "sweet-spot" closer to the more capable sub.

Obviously because one sub might generate different frequencies at different SPLevels, it might also play around with the waves in the room and create different peaks and valleys or not smooth it out at all.

The general question is:

What characteristics of a sub would make it a poor choice to match with another?
Frequency extension?
Significantly different frequency response graphs? (peak/valley)
Anything else you can think of?

I'm reading a lot more into paired subs to level out peaks/dips and provide a more thorough coverage of my space, the only thing is I have one Klipsch RW-12d but at a MSRP of $700 I don't want to buy another. I'd rather be getting a HSU/SVS/etc. sub with similar performance at half the price but I'm worried about the differences between them.

Now I know that the timbre question is pretty much moot, but what I am concerned about is getting a sub with significantly better low frequency extension and having that characteristic localize the sub or create a sub "sweet-spot" closer to the more capable sub.

Obviously because one sub might generate different frequencies at different SPLevels, it might also play around with the waves in the room and create different peaks and valleys or not smooth it out at all.

The general question is:

What characteristics of a sub would make it a poor choice to match with another?
Frequency extension?
Significantly different frequency response graphs? (peak/valley)
Anything else you can think of?

I'd run the Klipsch as a mid-bass sub and have the SVS/HSU run low frequencies. Have the Kilpsch next to one of your fronts as well, or colocate the subs.

Are you suggesting that I try and set a High Pass Filter on the Klipsch? (wasn't aware one could do that)

Are you then saying you believe that they would have a matching issue or is your advice merely toward the "should there be a potential issue this would eliminate it."

I might try to set the Klipsch somewhere close to the main's and then set a second sub directly around the listening position. Depends on how dialing in the sub goes.

Are you suggesting that I try and set a High Pass Filter on the Klipsch? (wasn't aware one could do that)Yes, that's what you'd have to do to even begin to implement his suggestion properly. I'm not sure he knows that, though. :)

Yes, that's what you'd have to do to even begin to implement his suggestion properly. I'm not sure he knows that, though. :)

That's why I included my caveat, I don't know any HPFilters for subs...

Anywho, how about the original question sivadselim? Do you have anything constructive to add to that?

That's why I included my caveat, I don't know any HPFilters for subs... You can get a HP filter for anything. An adjustable one (both frequency and slope) would be desirable, but you can get cheaper in-line RCA ones like THESE (http://store.hlabs.com/pk4/store.pl?section=9). The FMOD filters can be "doubled-up", with a 3dB attenuator in between, to double the slope (and the frequency), but they're still pretty limited both slope and frequency-wise. You can spend a lot of money and get an expensive adjustable cross-over and do what you want with it.

I assume you're aware of HSU's Mid-Bass Module (http://www.hsuresearch.com/products/mbm-12.html).




Anywho, how about the original question sivadselim? Do you have anything constructive to add to that?Oh............ :o

Not really. The dogma is that you shouldn't mix subs. But I can understand not wanting to buy another RW-12d. I know there are a lot of people in the same sort of situation who DO mix subs - you gotta do what you gotta do.

I don't think that the differences in 2 subs' overall frequency response curves would be that big an issue. It's the 2 ends of the frequency response curves that would be hard to wrestle with, particularly the low end. One sub (an SVS, for example) may have significant output below that of the RW-12d. So there'd be a frequency range over which both subs have significant output and they could be calibrated individually, as is done with identical subs, but the low-end frequencies of the sub with the better low-end capabilities wouldn't be calibrated properly.

I guess I would recommend getting the biggest or best sub that you can afford from the manufacturer you are interested in and give it a try. If you're unable to get them to coexist, if worse comes to worse, you can keep the new sub and sell the RW-12d.


EDIT: sorry craig john, I edited my post to say some similar stuff to what you posted, while you posted.

If you buy a sub with much deeper extension than the Klipsch sub, and run them together, you'll calibrate to the "combined" overall levels. However, this will reduce the individual level of each sub. The sub with the deeper extension will be reduced and the deeper frequencies will be reduced commensurately.

In your case, the RW-12d has extension to 24 Hz. Some of the Hsu subs go to 20 Hz and below. You'll be reducing the level of the sub with the lowest extension, giving up those juicy infrasonic dB's.

If you're looking just to flatten the FR over more listening positions, most any other sub can do that. I would look to pair another bass reflex sub with your current bass reflex Klipsch sub. I would not suggest a sealed sub paired with your bass reflex sub.

However, if you're looking for deeper extension and/or greater total output, I would say, sell your Klipsch sub and get dual Hsu's, or SVS's or ED subs.

Craig