double subbing

[BC Dave]

I have this huge area (big family room opening up into kitchen and beyond that living room and dining room with vaulted ceiling) and I am using a Paradigm PS-1000 v4 sub. For the fun of it on the weekend I also hooked up a second sub (Mirage BPS-150) to see how much more muscle there would be. I stacked the two in a corner and then found I had to cut the SW volume on my receiver to avoid having too much bass. We were watching a movie last night and my wife asked me to turn the sub(s) off because she could not hear the dialogue clearly. To me there seemed to be too much bass no matter how I adjusted the system. I am now back to using just the Paradigm sub and it seems to sound more balanced. The room (14 by 24) might be a problem, but at least it's not square. Anyone else find two subs overkill? Many would say the room is too large for just one sub, but I am not trying to blow the roof off when I watch a movie.

[Timn8ter]

If one sub gives you the bass response you like why would you add another? If you feel the room is a problem I recommend investing in a parametric equalizer like the one included in the Behringer Feedback Destroyer Pro before buying another subwoofer.
I use dual subs but it's not to get more bass. I have them to each side of my mains which gives a nice balance but I also feed the signal though the BFD to handle the big peaks and dips caused by the room. Works for me.

[cabron]

I too have a very large room ( larger than 12 x 24 ; with huge vaulted cielings.... I too like to blow the roof ... I too have tried to run two subs ( Athena asp-300, and, velodyne DSP-10 . I tried for weeks to get the right balance, without success. I gave up and now I only use the velodyne. The Athena sub is now in my bedroom,

I turned up the volume on the bass on the velodyne, and find it more pleasing.

If there is technique to get two subs to work, love to learn.

Thx

[sam9]

I read an article about of that very problem. I didn'y bookmark but as I recall it turned out the two subs are very hard to use well because the intereact with each other making room effects ever worse. I think, that the best solution was on opposite side walls one aimed forward and one back. The artical also considered even larger numbers of subs. By the time you got up to 6 or so things were looking pretty good. No mention of financial or other practical considerations was made.

[Timn8ter]

That would be the article found on the Harmon website.
http://www.harman.com/wp/pdf/multsubs.pdf
As I mentioned before, consider using a parametric equalizer.
http://www.timn8er.com/behringer_fee...troyer_pro.htm

[Woochifer]

I think your first problem is that you're corner loading two subs into the same corner. Generally, you should put both subs at different ends of the room. Also, doesn't sound like you're doing any measurements with a SPL meter -- need to start there and make sure that your levels are balanced properly to match the mains (generally, you should raise the sub about 4-8 db higher than the mains).

If it still sounds too loud after adjusting the levels to match, then you've probably got some room-induced problems that can only be solved by properly placing the subs (i.e. pulling them out of the corners and placing them at opposite ends of the room). In all likelihood, you have a big peak occurring at a specific frequency, and this occurs when reflected low frequency waves interact with one another. Peaks of 20db+ are actually pretty common when wave interactions create a reinforcement effect. The smaller the room, the greater number of frequencies that you will have this problem. The parametric equalization approach mentioned earlier will help because you have to measure your in-room response and then target the specific frequencies that require correction.

[Timn8ter]

The parametric equalization approach mentioned earlier will help because you have to measure your in-room response and then target the specific frequencies that require correction.

BINGO! If you don't measure, you don't know.

[mixadude]

I wouldn't consider trying to stack 2 unmatching subs without an analyzer, two parametrics and possibly a delay for time aligning them.

[sam9]

Here is something you might want to look into. I use something different myself, but I've heard fairly favoable things about this.

http://www.hometheateraudiocontrol.c...8&l1=5648&l2=#

[Geoffcin]

I have this huge area (big family room opening up into kitchen and beyond that living room and dining room with vaulted ceiling) and I am using a Paradigm PS-1000 v4 sub. For the fun of it on the weekend I also hooked up a second sub (Mirage BPS-150) to see how much more muscle there would be. I stacked the two in a corner and then found I had to cut the SW volume on my receiver to avoid having too much bass. We were watching a movie last night and my wife asked me to turn the sub(s) off because she could not hear the dialogue clearly. To me there seemed to be too much bass no matter how I adjusted the system. I am now back to using just the Paradigm sub and it seems to sound more balanced. The room (14 by 24) might be a problem, but at least it's not square. Anyone else find two subs overkill? Many would say the room is too large for just one sub, but I am not trying to blow the roof off when I watch a movie.

And it works well. The problem your having is that once you've added the sub, you have to go back and reset your sub balance settings. This is perfectly normal. If your receiver does not have an auto-calibration feature, your going to have to use an SPL meter. I would recommend the Radio Shack analog meter, about $40. Your also going to have to get a test disk with tone sweeps. Avia makes a good one, although a bit pricy. A good bargain one is the Digital Video Essentials test disk, you can get for about $14.

[kexodusc]

I'm slowly working on adding a 2nd 15" sub to my system. My previous attempts at using dual subs were basically miserable failures. But I think I approached it all wrong.

First and foremost I'd recommend having 2 of the same subs, or subs that are extremely similar in performance, especially frequency response. I used 2 Paradigm PW subs, the 2100 and 2200.
It didn't work well for a few reasons. The smaller woofer always seemed to be a bit faster or tighter than the larger one, which made the left side of the room sound sloppy (where the 2200 was). The lower bass extension gave a large tonal impalance to the room. Sub frequencies are fairly non-directional, but a lot of the energy they give off interacts with the location and can be quite easily localized. Furthermore, each sub interacted with the room differently, and because I didn't have many placement options in my last home, I got terribly inconsistent results. Super boomy at some frequencies, terribly diminished at others, and a noticeable off-balance sound that's hard to describe.

I think if you're going to do it, you have to do it right...2 identical subs, with similar environments for each. You can use treatments or eq'ing (in fact you'll probably have to) to make the environments appear similar. Make sure the phase is proper, you don't want them working against each other.

You wouldn't buy 2 different speakers to run as a stereo pair, why use two different subs?

If you are happy now, then realize that you would add a lot of cost for basically augmenting 2 octaves of information. Weigh that against your expected benefits before you decide to use two subs.

[Sir Terrence the Terrible]

I use double subs in opposite corners of the room. I had no problem with integration because I used the right tools. You must measure(I used a RTA, spl meter, special test signals, and acoustical knowledge) not just once, but quite a few times to get it right. equalization is absolutely essential.

Two subs are not a overkill in large rooms. Stacking two in the same corner is probably best, but that does excite room modes and nodes profoundly, much more so than a single sub might. Opposite corners cancels out side to side odd order room modes, which leaves only a single mode to deal with. So there are some benefits to opposite side setups.

If you are going to use two dissimular subs, they MUST be stacked in the same corner so they do not reveal the performance differences between the two. Using two identical subs is always preferred. Two subs require more work, but they offer more headroom, more overall volume, and each sub has to work less hard to reproduce X volume.

I have a requirement for my hometheater. All channels must have at least 6db headroom over the channels maximum volume. That is why I use two subs instead of one in my room.

[Timn8ter]

Just for those that may not know, a parametric equalizer is different than your standard graphic equalizer with slider controls. A parametric equalizer allows you to specify not only the frequency and the gain or loss, but also the bandwidth. Many come with 12 filters that are adjustable to any frequency as opposed to graphic EQs which are pre-set to a specific frequency and bandwidth. MUCH better!

[Sir Terrence the Terrible]

Just for those that may not know, a parametric equalizer is different than your standard graphic equalizer with slider controls. A parametric equalizer allows you to specify not only the frequency and the gain or loss, but also the bandwidth. Many come with 12 filters that are adjustable to any frequency as opposed to graphic EQs which are pre-set to a specific frequency and bandwidth. MUCH better!

Timn8ter can you remove the link to your audio store, members are not allow to post links to stores or certain brands of equipment without approval from the site administrator. Thanks!.

[Timn8ter]

You got it!