Do small rooms have more of a problem than larger rooms with having room modes where the bass frequencies cancel out? I suspect its based on a whole lot of factors, but does having a large room make it easier to avoid?
Do I Really Need a Sub?
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Mirolab
Well-known member
The size of the room affect the frequencies that the nodes will occur, but not necessarily more or less. Dimensions that are equal or multiples of each other is bad. Like, a 14x14 room will be worse than a 12x17 room. Higher ceilings are better. Vaulted/slanted ceilings are better. Larger rooms can always sound better because the reflective surfaces are farther away... but if it's got tile floors and plaster walls, it will be highly reverberant, and that will need to be tamed. Yes, there are LOTs of factors to how a room will sound.
Chops
Well-known member
Chops, sorry for my ignorance, but does that also hold true if we completely forget about video for the moment, and are only talking two channel audio? In my setup, one sub would likely have to be located near my LF and close to the corner. On the right side, my second sub could be farther from my RF (while still up front), OR with a scary, long and expensive balanced cable run, 'could' actually be on the right side of the room in the rear corner. To me that just doesn't seem right in a two channel setup...
Actually, I've been referring to 2-ch audio the entire time.
Also, instead of purchasing long expensive balanced cables, you can (if your subs allow it), speaker cables from your main amps to the high level inputs on the subwoofers, which I believe sounds better anyway. And to do so, you do not need expensive speaker cables, just inexpensive speaker cables or even simple zip cord.
Your subwoofer locations that you described would be perfectly fine as long as they actually help out with room modes and such. Adjusting levels and phase properly will work wonders in situations such as yours.
Thx Chops. Unfortunately, I let my situation drift across a couple of different threads. I now understand that your preference is to use high level inputs, and that gives me much more flexibility!
Chops, sorry for my ignorance, but does that also hold true if we completely forget about video for the moment, and are only talking two channel audio? In my setup, one sub would likely have to be located near my LF and close to the corner. On the right side, my second sub could be farther from my RF (while still up front), OR with a scary, long and expensive balanced cable run, 'could' actually be on the right side of the room in the rear corner. To me that just doesn't seem right in a two channel setup...
BDH55, I don't know if you have heard of this method though it sounds strange.
It's call "the sub crawl". With this you place your sub in your listening position as close to your listening level as possible.
You then put music on with a good bass line. After that you do literally what the name says. Get on your hands and knees and travel your entire room at the lever your sub would be. You will clearly find the places where the best bass is. Those are the locations you should start with for your subs if posssible
Even if you can't leave them there try it you will be a believer.
Once you stop laughing at what you just read. Give it a try, it truly works.
Gordon Gray
Well-known member
Well recognized as a very valid method.
Thx Brad! Roberto also turned me on to the YouTube ML video with Peter Soderberg setting up their subs, and I think this sounds like what he did. It did 'look' a little odd, but I guess if this is the best method, I will just have to figure out how to get it done. While I can handle the crawling around and listening part... the challenge will be trying to position a 140# (or even 96#) sub at my listening level. I just don't have the strength or balance anymore of you youngsters (which also creates problems moving main amps, etc). Thinking about this though, my guess is that sub position should be the same regardless of the sub, correct? If so, I would have an easier time doing the sub crawl with my existing Descent i than I would with my planned BF 212.
Only other thought is since I am 'considering' going with two subs, how do I do the sub crawl? Do I go ahead and find the location for my left channel sub, and then repeat it with the right channel sub?
Great question! I think the two subs will interact with each other and maybe cause interference? Might be tricky.
Chops
Well-known member
You would just leave the sub in your listening position and do the "crawl" around the entire room, side to side, front and rear, and find what multiple locations sound best. Those multiple locations is where you would put the multiple subs. After that, you would just have to adjust phase and gain independently as they would be different distances to your listening seat, so loudness and timing from each sub would be different.
Yes, it's a little tricky and a little more work, but it's not terrible. You'll essentially be doing twice the work of dealing with a single sub is all. Not hard to do at all.
So I guess that the idea might be that youre better off getting 2 lesser subs as opposed to just one sub that is at the top of your budget?
Would 2 of these MartinLogan | Dynamo 1600X sound better than one of these MartinLogan | BalancedForce 210
2 dynamo 1600x vs 1 balanced force 210?
Would 2 of these MartinLogan | Dynamo 1600X sound better than one of these MartinLogan | BalancedForce 210
2 dynamo 1600x vs 1 balanced force 210?
sleepysurf
Well-known member
If using two subs, the other option is to run them connected as "dual mono" subs, especially when crossing over @70 Hz or below. That can be easier to dial in with the mains. Unfortunately, the room, main speakers, and sub(s) all interact with one another, so it takes lots of experimentation. Even if using ML BalancedForce subs (with Anthem Room Correction and downloaded crossover filters), you still need to experiment to get smoothest overall response (plus phase/timing correct).
Chops
Well-known member
With those two exact models, I would probably say going with dual Dynamo 1600X's would be the better way to go. I'm a strong believer of relying on physical/acoustical solutions rather than DSP. Less processing of the sound, the better as far as I'm concerned.
Plus, any time I have used DSP for any kind of correction in a home system, it boosts frequencies so much (to compensate for room suck out) that it causes weird resonances elsewhere in the room and makes the bass seem too heavy and sluggish sounding, or it takes away so much output at certain frequencies (to compensate for room gain at those frequencies) that the overall sound suddenly lacks proper body, dynamics and impact.
Very rarely have I had DSP actually do as good a job as using physical means to make the room corrections.
I agree with what Chops and Sleepy posted.
As far as better or lesser quality subs. There is a very interesting thread on the Whats Best Forum. An engineer studied and wrote about using 1 high quality sub and multiple lesser quality subs. He felt this provided excellent results. I will look for the thread and post a link or explain how to find it.
When I set up the subs in by room, I did the sub crawl and it turned out the the 2 strongest signals were at the mid point of the side walls about 12" out into the room. The next 2 best choices were mid way on the front and back wall 12" into the room. That is how I placed mine.
I realize not everyone has the ability to put them where ever the best spot is called for. Just use the best spot that will work for you.
Even when I only used 2 subs I ran them as dual mono not L & R. I think there is to much chance for the signals to interact in a negative way. You need to try both and see what works best for you.
On my Depth i's the possible adjustments on the subs was much better running them speaker level connections than line level. I run speaker wire from the left and right amps to the first sub. I then ran Belden audio coax from the sub out of the first sub to the l right input of the next sub. Then just continue to each successive sub.
I feel your pain BDH55. I'm 67 and I know Chops and Sleepy aren't youngens any more either. Sorry guys. Sometimes you just need to call in some reinforcements.
As far as better or lesser quality subs. There is a very interesting thread on the Whats Best Forum. An engineer studied and wrote about using 1 high quality sub and multiple lesser quality subs. He felt this provided excellent results. I will look for the thread and post a link or explain how to find it.
When I set up the subs in by room, I did the sub crawl and it turned out the the 2 strongest signals were at the mid point of the side walls about 12" out into the room. The next 2 best choices were mid way on the front and back wall 12" into the room. That is how I placed mine.
I realize not everyone has the ability to put them where ever the best spot is called for. Just use the best spot that will work for you.
Even when I only used 2 subs I ran them as dual mono not L & R. I think there is to much chance for the signals to interact in a negative way. You need to try both and see what works best for you.
On my Depth i's the possible adjustments on the subs was much better running them speaker level connections than line level. I run speaker wire from the left and right amps to the first sub. I then ran Belden audio coax from the sub out of the first sub to the l right input of the next sub. Then just continue to each successive sub.
I feel your pain BDH55. I'm 67 and I know Chops and Sleepy aren't youngens any more either. Sorry guys. Sometimes you just need to call in some reinforcements.
If your amp is not supporting bass management (for the individual subs) I think you need to have a symmetric setup not to end up with unwanted bass issues
Chops
Well-known member
This is very true. I don't consider myself old by any means, but getting down on the ground, and worse, getting back up is getting a bit more difficult these days. And we still need to get together sometime (it was mentioned on your system thread several years ago). But that's another story for another thread altogether.
This ultimately depends on the capabilities of the subwoofers in question. If they only have a phase switch (0* or 180*), then I would agree. However, if they have in addition to that phase switch a constantly variable phase control knob such as that on my JL subs (0* to 270*), then having the subs in nonsymmetrical locations should not be an issue. Only time is involved in dialing them in so that they play nicely together.
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This ultimately depends on the capabilities of the subwoofers in question. If they only have a phase switch (0* or 180*), then I would agree. However, if they have in addition to that phase switch a constantly variable phase control knob such as that on my JL subs (0* to 270*), then having the subs in nonsymmetrical locations should not be an issue. Only time is involved in dialing them in so that they play nicely together.
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I tend to disagree - you have an issue with the distance say one Sub nest to the listening position and one in front at the screen. My supplier could not get it calibrated correctly due to the time factor so I dumped my old sub altogether and only use the Dynamo 1100 today (which actually is enough I think)
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I tend to disagree - you have an issue with the distance say one Sub nest to the listening position and one in front at the screen. My supplier could not get it calibrated correctly due to the time factor so I dumped my old sub altogether and only use the Dynamo 1100 today (which actually is enough I think)
Nuri58, I had a, not totally unrelated, placement issue that was quite surprising with my current setup.
My listening room was previously a sunroom on the back of our home. The person that built it might not have owned a level or tape measure.
When I began the transformation to the listening room I discovered the room had opposing walls that were different lengths. One set 24'-0" the other 24'-7". The end walls were 16'-0" and 16'-7". Not having parallel walls is not a bad thing if planed.
There was a 4" step down into the sunroom. When I checked to level the floor and stiffen it, the floor was 3 7/8" lower in a diagonal corner.
Anyway when the room was finished I place the side wall subs where the strongest signal was from my sub crawl. I used the exact center of the long walls, that seemed to be the ideal location. No matter how much I adjusted them there was always a bump in the aprprox 70 Htz, if I remember correctly, area.
It wasn't until an EE friend came over and measured we figured it out.
He adjusted the subs any way possible but we ended up back at my original settings. It wasn't until he stared at them for a few minutes and said the left sub is not the same distance from the main speaker on the left side as the right pair is.
He was right. I had placed them in the center of the wall by measurement and with that wall being 7" longer it was 3 1/2" further away. We moved it 3 1/2" down the wall and the bump was gone. I can only guess that the subs on the front and back wall are so much different in distance to the speakers it is not an issue.
My listening room was previously a sunroom on the back of our home. The person that built it might not have owned a level or tape measure.
When I began the transformation to the listening room I discovered the room had opposing walls that were different lengths. One set 24'-0" the other 24'-7". The end walls were 16'-0" and 16'-7". Not having parallel walls is not a bad thing if planed.
There was a 4" step down into the sunroom. When I checked to level the floor and stiffen it, the floor was 3 7/8" lower in a diagonal corner.
Anyway when the room was finished I place the side wall subs where the strongest signal was from my sub crawl. I used the exact center of the long walls, that seemed to be the ideal location. No matter how much I adjusted them there was always a bump in the aprprox 70 Htz, if I remember correctly, area.
It wasn't until an EE friend came over and measured we figured it out.
He adjusted the subs any way possible but we ended up back at my original settings. It wasn't until he stared at them for a few minutes and said the left sub is not the same distance from the main speaker on the left side as the right pair is.
He was right. I had placed them in the center of the wall by measurement and with that wall being 7" longer it was 3 1/2" further away. We moved it 3 1/2" down the wall and the bump was gone. I can only guess that the subs on the front and back wall are so much different in distance to the speakers it is not an issue.
Location! Location! Location!
Charles, I don't think of myself as old either but, there are activities as you describe that are a challenge on many days.
My thought process. I'm sore to day, I guess I should just relax and listen to some music.
Any time you would like to come this way my door is always open.
I watched them rounding up the Swans this morning on the local news for the yearly checkup. That won't mean much to most people.
My thought process. I'm sore to day, I guess I should just relax and listen to some music.
Any time you would like to come this way my door is always open.
I watched them rounding up the Swans this morning on the local news for the yearly checkup. That won't mean much to most people.
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