Can two subwoofers reduce a bass problem?

Yes, but, << whispers>> have you tried bass traps + EQ?  It's like magic.

Yes. Here's why.

The reason we have to move subs around is one sub always causes lumpy bass, some areas way louder than others. So you move the sub trying to find the least lumpy location. Which changes constantly depending on the frequency. This happens no matter how great or powerful or expensive a sub you buy. 

It also happens when you use more subs. However, and this is a big however, having more subs lets you run each one a lot lower volume. So one of the four is too loud and lumpy at one frequency at one location, way too quiet everywhere else. Big deal. No longer matters. Because you have three more. Each of which is at a different location causing different lumps or modes and not nearly loud enough everywhere else. 

But with four all the lumpiness averages out to something quite smooth. Its possible with four to have bass that is both deep and powerful and tight and articulate, as well as smooth. Much more so than you could possibly get with any single sub no matter how good.

Also with just one sub you have just one crossover or EQ. But with four you can adjust each one independently of the others. That's if you run four powered subs. Or if you do like me and some others and run two per amp, or four per amp, whatever. Main thing is any way you do it four beats one even when total cost is held equal.

@OP, 
Yes, using 2 or more subs help with room nodes.
I would PM Duke (audiokinesis), he manufactures the Swarm system.
Though I know you probably don't want to invest in that, I think Duke will be able to steer you in the right direction with regards to sub placement.
Bob

4 is better than 2, and 2 is better than 1, yet in my system one REL S/5 SHO works great...friend with almost identical system sounds best with 2 REL S/3 SHO...so, it depends...

It's interesting that your able to narrow down the problem frequencies.

You should be able to get a decent low frequency presentation at the listening position with one subwoofer by locating your rooms greatest mode using the Crawl method.
https://www.youtube.com/watch?v=AV3oLLMgS-M

During this test you might want to map out all your rooms modes in the event you add multiple subs. 
For reasonably priced long interconnects check out Blue Jeans Cable or Monoprice. Good luck with it.

BTW, OP you never mention if your problem is a peak or a null.

If it's a peak, EQ is your friend.

@erik_squires 
48 and 127 are peaks and a actually have a dip at 70.
EQ; from where do I get an analog (I'm listening much on LP:s too) mastering EQ cheap? I can't ruin the sound with some cheap budget EQ.


A strange thing happend when I replaced my old Supra Annorum speaker cable to Kimber 8TC. Besides giving a more open, wider sounstage with a tighter bass the problem with the bass peaks also was reduced. Now it's more like the peaks has become more narrow.

I'm looking at REL T5i and REL T Zero and wonder if I get a better result with two T Zero than one T5i. With two T Zero I might counteract my bass problems a bit, but on the other hand I will not get a real low bass.
With a T5i I will get low bass but maybe it will increase the bass problem again.

My smallish room is not just a listening room so I can't just put four subwoofers anywhere and build bass traps or a Helmholtz.

Now I remember why I bought a new headphone amp and new headphones:)

I know there are a lot of advocates of multiple subs, something I will try one day.
But right now I have a single Martin Logan 10 inch sub complimenting my Maggie's and I think it sounds PDG.
Of course until I try two I will never truly know but I do believe one can work in the right room and set up.

Get a miniDSP equalizer on the sub only. You'll love it. :)

Don't try to fix the null too much. If it resists, leave it alone, but clipping the peaks and tilting the bass the right direction (peaking around 20hz, about 1.5 db/octave down after that) will be incredible. :)

Which mini dsp do you recommend Eric?

oh, I mean, without bass traps, nulls are hard to fix. If you get some, then you should find the nulls are easier to pry.

As for which, for RCA connections:
https://www.minidsp.com/products/minidsp-in-a-box/minidsp-2x4-hd

For balanced:

https://www.minidsp.com/products/minidsp-in-a-box/minidsp-balanced-2x4
The HD part means 96/24 sampling is used.

Best,
Erik

Thx Eric!

So you think you can use one of these on just the sub only?

Most interesting.

Erk, I have an extra set of rca outputs on my pre which I would use to go the the stereo subs. Would I stick the minidsp between the pre and the subs? Don't need to touch the signal of the mains?

To uber and bstatmeister:

That's what I do, so long as the pre signal is controlled by your volume control.

The bad news is you have no control over the satellite's frequency response. On the other hand, you also can't mess it up.


Since the miniDSP is so flexible however, you can really tailor the sub's output for maximum integration with the satellites.


If your current satellites are ported, you may find it easier to integrate by stuffing those ports closed.


The key here though is measurement and delicacy of setting. Worthwhile reading the white papers on their site and hanging out in the Room EQ Wizard forums.  I use OmniMic for my measurements. It's a little more expensive but I love how easy everything is and the built-in DSP curve simulator. It lets me try out different curves and see them before I copy them to miniDSP.

A very interesting way to control the bass frequenzies. But sadly it's no option for me since I have an old integrated tube amp and the only outputs are those to the speakers. 
I'm looking at the REL T5i (and T Zero) because I think their high level input is the best way for me to connect the sub to an amp.

"....I'm looking at the REL T5i (and T Zero) because I think their high level input is the best way for me to connect the sub to an amp."

simna,

The High Level (Speaker) input is REL's preferred way of connecting their subwoofers and is the route I went with my T/5i. As recommended by REL, the T/5i is located in the corner behind the main speakers (KEF LS50s) and I'm very pleased with the results.

FWIW, I briefly considered using two T/Zeros for better balance but I knew that I would not be happy with the limited bass output. Besides, I can always add a second T/5i later on if I feel the need.