Speakers to alleviate room anomolies

I have a suckout of 8db from 58 -70 hertz which is taking the life out of the music. I currently have Von Schweikert VR7SE an added a velodyne dd18 which took away the problem. It gave the bass energy in my room of 30 x20x10. It seems I do not need the big cabinet speakers[VR7SE] if the woofers aren't throughing enough. Speakers with active woofers like the evolution acoustics mm2 have been recommended. Any other ideas of speakers in conjunction with the velodyne dd18 to make my room sing again.
You replace the VR7's with something else and you still are going to have the problem w/o the DD18. I don't see how changing the main speakers will do anything other than change the amount/frequency of energy the DD18 has to add to overcome the bass deficiency. What are you trying to accomplish; it is unclear to me?
Something is not right in what you're stating. The 58 to 70Hz suckout is fairly narrow and not that deep. I don't see how it would take the life out of the bass. Your room dimension are not good. Rather than swap equipment I would recommend you hire an acoustic engineer to measure your room and see what he recommends.
You want to make your room "sing again". So does that mean it sounded good at one time, or maybe that it sounded good until you measured the system? Now that you have measured a minor flaw it sounds bad to you. What did you change that made you unsatisfied? If the sub has corrected the problem, what is left to solve?

Speaker placement and room treatment are your best bet. Then when you're all done with that, the room will still not be perfect, only better than it was.

Vandersteen Quattro or 5's have built in bass adjustments which might be a better match. Audio Kinesis makes a system with multiple subs to even out bass response. These are just a couple of examples that come to mind if you are determined to change speakers.
Agreed with Rhljazz... Vandersteens have the ability to closely match the room. It works very well when you have a Vandersteen dealer set them up. They use a mike and a special CD to adjust the various pots built into the speakers's amps.
Your suckout is pretty precisely cenetered on the fundamental of a kick drum - just kinda BAD LUCK - so it probably feels more pronounced than it might otherwise. The only thing IME that will address this type of issue (below 80ish hz) is EQ, like the room corrected Velodyne DDs or perhaps the adjustable Vandys.

If the idea is to keep the DDs (probably a very good idea), than you've got a ton of choices. I use Ohm 100s (omni) and sometimes Maggie MMGs (planar). But, honestly, any speaker with limited low end response will likely work well with the DD and provide the smaller cabinet you seek. Smaller VS might make sense if you like your VR7s, but want a smaller box.

Good Luck

Room effects dominate in the bass region, and the peak-and-dip pattern is a function of room dimensions (and damping), source location, and listener location. In other words, move the bass source(s) and/or the listener and you re-arrange the peak-and-dip pattern.

One solution is to have as many bass sources as is practical, and have them spread asymmetrically as far apart as is practical. This way each bass source interacts with the room differently, producing a unique peak-and-dip pattern at any given listening position, and the sum of these dissimilar peak-and-dip patterns will be smoother than any one of them no matter how optimally placed. And if you want smooth bass over a large listening area, this technique is more effective than equalization (it is arguably more effective than equalization for a single sweet-spot as well, based on comments from people who have tried both).

If I understand correctly, by adding the Velodyne you now have three bass sources in the room, so that might be the reason why it smoothed out the bass for you. If you keep the Velodyne and go with small speakers that don't contribute much in the bass region, you may well end up back where you started.

In my opinon the theoretical ideal is multiple subwoofers scattered around the room, and they can be fairly small. In this scenario the main speakers don't need to carry the deep bass, so they can be smaller... but for aesthetic reasons few people find it practical to go the multisub route.

Duke with the posters question in your opinion would you still play full range on the main speakers or cutoff the lows and direct them to the subs;I would think this would be the correct choice but I thought I would see what you thought.
Adding the subwoofer did correct the problem. It doesn't seem right having a huge expensive main speaker not doing the job.There are 2 twelve in woofers on each side not providing punch.I also thought I didn't have enough power to drive the woofers on the VR7's but all my other main speakers[Dunlavy 5] seem to have the same bass shy charateristics. Its time I get Duke here to figure this out.

In other words, move the bass source(s) and/or the listener and you re-arrange the peak-and-dip pattern.
I don't see how moving the listener will change the peak/dip pattern. The pattern is what it is, as you said, based on the source location(s) and room dimensions. Moving a microphone or pair of ears around the room won't affect the pattern.
Bob_Reynolds: I respectfully disagree. There are always spots in a room that cause nulls and bumps as well. Finding a proper place for the listening position as well as for the speakers is critical. Having a speaker that is adjustable in the bass region certainly will make it much easier to dial the system into the room.

Snook2: Visit our website which has very complete suggestions for speaker and listening position placements.


You will find this under the support tab on our website. You might find if you take the time to follow the instructions on-line, that you might not even need a subwoofer. You might also find that your existing speakers do the job you expected.

Hopefully that helps.

Jonathan Tinn
Evolution Acoustics
Rleff, in general it's desirable to have a lot of low frequency sources in-room, as long as you aren't stressing the main speakers and as long as you aren't over-emphasizing some portion of the bass region or otherwise creating a problem (like your wife says you're sleeping on the couch). Of course in some cases it's more desirable to relieve the woofers in the mains of having to make long bass excursions, so the best answer depends on the specific situation.

Snook2, it doesn't matter how capable the main speakers are, the room's effect will dominate in the bass region. There are four approaches to smoothing the bass that you can use singly or in combination:

1. Speaker and/or listener re-positioning. By all means visit Jonathan Tinn's speaker placement page. If it's aesthetically acceptable, you might try an asymmetrical setup. Imagine looking down on the speaker-listener-speaker triangle within your rectangular room, and imagine rotating that triangle clockwise or counter-clockwise maybe 15 or 20 degrees. Don't go all the way to diagonal; that would again be symmetry, and asymmetry is usually your friend in the bass region.

2. Add low frequency damping in the form of bass traps. This works well at not only taming peaks but also at filling in dips. I don't think bass traps can eliminate an 8 dB dip, but they can make it shallower.

3. Equalization works well for a small listening area, but it's a two-edged sword if good sound in a wide range of listening locations is a high priority. You see, boosting a dip or notching out a peak in one location can result in boosting a peak and notching a dip in another. The better equalization systems use readings taken in a wide variety of microphone locations and then calculate the appropriate EQ curve. Global (room-wide) bass problems are good candidates for fixing with EQ, but in my opinion localized bass problems usually are not.

4. You can use multiple (imho preferrably asymmetrically placed) bass sources, which works for reasons I've described in my previous post. Credit to Earl Geddes for teaching me this approach. Note that multisubs reduces the variance from one listening location to another, so that any remaining problems are likely to be global and therefore are good candidates for fixing via equalization.

Bob Reynolds, what I meant by "peak and dip pattern" is the frequency response at a specific microphone or listener location, rather than the room-wide pattern. If we could look at a map that showed the frequency response throughout the room, that "peak and dip pattern" would indeed depend only on the source(s) and the room - not where ears or microphones are positioned within the room. My apologies for the ambiguous wording.

Jonathan Tinn, I'm not saying that listener position doesn't affect what we hear; obviously it does. There are peaks and dips throughout the room and they are there whether I'm in the room or not. My walking around the room does not influence, appreciably I suspect, the acoustic behavior of the room dimensions and sound source locations.

My post was a slight poke at Duke for not being as precise as I know he is.
Bob_Reynolds: I like poking fun at Duke as well. He and I go back a long time.
Just 8db suckout at a certain frequency is not enough info to sort the problem out. The 8db drop could be from bass cancellations, bass leak or an object absorbing too much. THere are other parameters Rt 60, impulse response when you are looking to solve this problem. I am no expert and currently working on room issues too. Sub is ok but probably not the best solution. Best i to get professional consultation.