Room Acoustics and Speaker interaction.

I would like to have a secondary system in my small den which is only 11.5ft by 11.5ft with only a 7.5ft ceiling. Very small and very square...yikes!

So, because the room is so small, the speakers need to be close to the wall that resides behind them.

So this got me thinking about speaker types: sealed/front ported/rear ported, etc as I want to avoid a booming bass. But then I was it really the ports that are problematic or is it just certain low frequencies that are reacting to the room modes? Any thoughts?

How does one determine what frequencies to watch out for in your particular room?
I have a small room, 11x12 and use a Pair of Merlin TSMXe sealed speakers, works fine with me, about 24 inches from back wall.
There's a room mode for each dimension of the room. See the calculators at Harman:

Also, checkout the whitepapers written by Dr. Toole. As Dr. Toole says in one of the papers, you hear the room below 350 Hz and the speakers above 350 Hz.
Unfortunatly, I will only be able to have about 12 inches behind the speakers. Thank you Bob for sharing your links with me.
Why not mark a spot out from the wall with tape. When you decide to do serious listening move them out towards the marked floor?
Hi Schipo,

I understand what you are saying......but, here is my wife's answer to your suggestion:

"My husband already has a dedicated listening room which houses his "reference" system in. He is free to do as he likes in "that" room and is welcome to do his "serious listening" in there anytime he would like. As to "my" den, he is welcome to have a nice set of speakers in here as long as they fit into my decor and are unobtrusive.....which means they will NOT be pulled out into the room. This room is small enough as it is....I do not want to be tripping over his speakers besides."

So there you have it. I have a few obstacles I am dealing with......a very small room, one that is square no less, and my wife.......(just kidding, honey!)
I think you're realizing that the room dominates when it gets that small, and that nothing you do will alleviate the problems with placement near a wall behind the speakers, which will cause all kinds of response anomalies in the lower mids and upper bass.

You might consider a couple of very small satellite speakers and find a hiding spot for a small woofer that you can optimize for the listening position.
No_regrets, why would you want to put speakers in her room? Would you like if she was putting things she likes (e.g. shoes) in your dedicated room? :)
Good point Nvp. We spend a lot of quality time together in this small den, and we both truly enjoy listening to music together. We both would like to be able to do this together in this small den. However, she does not want this to look like a stereo room, due to the fact that she has already allowed me to have a dedicated listening room for my reference system elsewhere in the house.
You can can make room look like kings bed around usind some linen curtains around room ,it would help avoid booming bass :)
The main speakers cannot be too small or the sub will make itself known; you'll have to set the low pass filter on the sub too high to integrate with the main speakers.

A reasonable solution is to use room mode correction either by 1) using a decent AV receiver (Anthem) or prepro or 2) a monitor controller that has room mode correction. Take a look at the ERGO at KRK or the MSC1 at JBLpro. I've used the JBL MSC1 in my office system when I was using a small sealed SVS 12" sub with KRK VXT6 monitors. I was very happy with it.

Both JBL and KRK have very respectable active monitors and subs.
IMO, both Luvs2listen and Bob_reynolds have given very good advices. For speakers, I would recommend Dynaudio sealed monitors e.g. Audience 42 sat or Contour S R, complemented with a sealed subwoofer.

Also, whether or not you will excite any room modes, it depends on how loud you are listening. For soft listening sessions you may not excite any room modes, so your square room may not be a problem after all.
Yes, indeed. There have been some great suggestions made by all of you here. It looks as though I have some more research to do. I appreciate everyone's contributions in trying to help me get good sound in this little room.
It's your room not the speakers. My suggestion is get whatever speaker you like, put it where you want (against the wall) and get a tact 2.0s preamp and do the room correction. It will do wonders. No boomy bass.
It's your room not the speakers

The OP did not talk about any problems, only asked opinions about speakers that might work fine in his small room. While I agree that electronic correction/equalization can do wonders, it is naive to think that you can put your speakers anywhere in the room and then get away with this by running the room correction set up procedure. Electronic equalization should be used as little as possible, i.e. you put the speakers and sub in the best place possible and then run room correction set up procedure.

I'm not saying the op has any problems. I'm just saying the room has more to do of the booming bass than the speakers themselves. You're right about the limitations of room correction but seeing from the options of the op, the room corrections seems to fit him best. His biggest concern was booming bass and that was MY suggestion.
Another vote for electronics with room correction software. Audyssey (particularly XT 32) is another excellent option.


Bmwmcab, my initial impression was that the OP is asking for speaker recommendation. However, after re-reading the initial post it is clear that that may not be necessarily the case. Though, I still can not tell whether the OP is just concerned about booming bass or he has already tried speakers in that room and knows for sure this is an issue. Sorry.

Regarding some of the OPs initial questions, the dimension of the room determine the modes that will be amplified or absorbed by the room. There are quite a few online room mode calculators (google "room mode calculator"). A few times I have used this one:

Room mode calculator

However, one should keep in mind that the position of the speakers relative to each other and to the room walls has a bit influences on the interference pattern. The speaker ports are also very important in this regard as they are additional bass sources. There are other additional variables, e.g. material from which the walls are made, listening level, neighbor rooms, etc.. Thus, unless one measure properly the response of his/her room, nothing is written in stones. The output of all these online calculators should be considered as a starting point.

Electronic management of the bass, as first suggested by Bmwmcab, is the most effective way to go. However, if you will used speakers design to be placed near room boundaries and/or listen at low level electronic equalization may not be necessary.
When I study about where to situate a pair of speakers I usually take some meditions:
1- find best frequency bass response (<200hz) in the room. You can play with speakers position AND sweet spot position
2- try to adequate the room reverberation time from 200hz to 3150Hz according to your taste preferences (room monitoring studio has typical values from 0,2 to 0,4). For this you will need acoustic treatmen.
3- find the best response over 200hz, play with toe in amd tilt of the speakers

Be careful with rear bass ports, they don't like rear walls...

Good luck!!

No offense taken. We're all here to help each other out and try to give advice to the best of our knowledge. Given the size of the room and where you want to place the speakers, I would go with Nvp's suggestion and get a front ported speaker and see how it goes. If it's still too boomy, consider room correction.
Hi guys,

Yes, I have tried some speakers in this small room already.

I've tried my late 1960's vintage 12" Tannoy Monitor Golds in custom cabinets that had dual front ports. Very boomy on the bass notes.

I've tried my late 1960's vintage Wharfedale W25's which are in a sealed enclosure, two way speaker with 8" woofer. No problems whatsoever, except that due to age, the cabinets are not up to my wife's approval for this room.

I've been thinking about the little Harbeth P3esr which is a sealed box, but it is a lossy design though. Or possibly the Harbeth M30.1 which is front ported, but a little larger than my vintage Wharfedale W25.

I've also been considering the DeVore Gibbon 3XL which is front ported.

There are no dealers near me for any of these speakers, however I will be attending the AXPONA show in Chicago and will be able to at least hear the Harbeths there for the first time.

So in answer to some of the questions from posts above....yes, this little room can have a booming bass problem as evidenced by the use of my Tannoy Golds, but at the same time, no problem exists with my sealed Wharfedale W25's.

So that is what lead me to ask about speaker design. Is the problem with ports, vs sealed design? Or is the problem with the amount of air the 12" gold driver can move vs the 8" driver of the Wharfedale?

I won't be buying anything until after the Chicago show. I appreciate everyone's willingness to help me with this and the sharing of everyone's thoughts and ideas. This IS a GREAT forum with very HELPFUL people. Thank you to EVERYONE.
"I've been thinking about the little Harbeth P3esr which is a sealed box, but it is a lossy design though."

What does the fact that it's a lossy design have to do with your situation and whether it will sound good in your room?
Hi Chayro,

Probably absolutely nothing.....I honestly really do not know. As I was talking about different speaker designs (sealed, ported, etc) and knowing that the Harbeth is lossy and specifically part of it's design, where some other speakers are not, I was simply just mentioning it.

As I do not know if this fact would play a role in my situation, I was hoping that someone that has more knowledge and experience with them than I might chime in.

Best regards,
Unfortunately, my experience has been that you just have to try different speakers and hope that the response clicks with the acoustic properties in your room. When you don't have placement options within the room, you just have to hope you find something that works. OTOH, Harbeths are designed to be used in actual control rooms and for nearfield listening situations, so you're on the right track, IMO.
I have the same situation in a bed room, and in regard to speaker placement, I discovered diagonal works best with the phantom center channel in the corner.
No-regrets, if the wife is ok with he Tannoys then I would try them again only this time stuck something into their ports, e.g. some foam or sponge, rolled socks will also do.

Keep in mind that the density of the thing you put into the ports will significantly affect the bass output of the speaker, i.e. the denser the material the less bass output the speaker will produce.
Hi Nvp,

Thanks for the suggestion. I actually did try this with foam a while back. Although it did reduce the bass output, it also messed with the rest of the sound. It just didn't sound right. It lost its naturalness, it's intimacy, and to my ears, I didn't like it.

Maybe I need to experiment more with different materials, etc. I still think its a good suggestion and me be helpful with other speakers or with different materials.
It just didn't sound right. It lost its naturalness, it's intimacy, and to my ears, I didn't like it.

I know what you mean No_regrets. You should try to use something softer, also do not stuff the speaker ports. The speakers need to "breathe" a little beat.

Of course, I am not trying to stop you to buy new speakers. That is always fun!