My mains (mythos 4's) have a -3db lower limit of about 104 Hz, so it looks like setting speakers to "small" with a 100 Hz crossover would be the best way to go. However, my understanding is this may make the sub more localizable.

However, I have 2 SVS PC-12 Pluses coming (soon, I hope :)), and my plan is to place each of them them in front right next to the 2 mains.

Question: Since there will subs next each of the mains, does localizability then become a moot point?

The reason I ask is that there is a possiblity of upgrading to the Mythos Ones, which should theoretically allow a lower crossover; however, at this point it just wouldn't seem to provide much of an advantages in terms of this issue.

Thanks in advance for your thoughts on this.

P.S.: Before someone points this out--Yes, I probably should have considered just getting the Def Tech STS or ST, and then I wouldn't even have to ask this question.

Localization becomes much less critical if the subs are right near the mains. In fact, there are some nice advantages to running higher crossovers if the localization problem is eliminated. The subs will usually present better slam in the 80 to 120 hz range than most mains. Also, it lifts a heavy bass burdon off of your main amps and gives them and your main speakers more headroom. The end result is cleaner mids and highs.

Localization becomes much less critical if the subs are right near the mains. In fact, there are some nice advantages to running higher crossovers if the localization problem is eliminated. The subs will usually present better slam in the 80 to 120 hz range than most mains. Also, it lifts a heavy bass burdon off of your main amps and gives them and your main speakers more headroom. The end result is cleaner mids and highs.

Agreed, a pair near the mains would do him well.

Even a pair crossed high nearfield but equal distance apart (let's say both sides of a couch) help confuse the mind as to directionality.

Hmmm...thanks! I never thought of raising the crossover--would 120 Hz be about right in a set up like this?

Considering the lower limits of the mains, that's a good starting point to try. Also experiment with slightly higher crossovers to see how they compare.

Even a pair crossed high nearfield but equal distance apart (let's say both sides of a couch) help confuse the mind as to directionality.

I have this same set-up with 2 MBM-12's on either side of my couch. You still need to be careful as the bass will start to move to the back instead of the front stage. At least that is what I have experienced in my room. The highest I could go was 100Hz before the bass was obviously coming from the back (with music as my reference material). With movies it could be different. My main sub is in the front right corner. The transition to lower Hz. would then move the bass back up front. With both MBM's facing forward and the main sub up front, everything sounds like it comes from the front stage.

Thanks to all! Very helpful--I'll give these ideas a try.

I have this same set-up with 2 MBM-12's on either side of my couch. You still need to be careful as the bass will start to move to the back instead of the front stage. At least that is what I have experienced in my room. The highest I could go was 100Hz before the bass was obviously coming from the back (with music as my reference material). With movies it could be different. My main sub is in the front right corner. The transition to lower Hz. would then move the bass back up front. With both MBM's facing forward and the main sub up front, everything sounds like it comes from the front stage.

Have you tried reversing the sub placement (MBM's with mains, true sub nearfield)? I have mine that way and can run high crossovers with no localization issues.

Bill

Have you tried reversing the sub placement (MBM's with mains, true sub nearfield)? I have mine that way and can run high crossovers with no localization issues.

Bill

interesting!

Have you tried reversing the sub placement (MBM's with mains, true sub nearfield)? I have mine that way and can run high crossovers with no localization issues.

Bill

Bill,

Yes I did. I was able to easily run a xo of 120Hz. I tried it for awhile, but did not like the localization I was getting from the nearfield main sub. In addition, I was able to get some good room gain in the low end by placing the main sub in the front right corner. From 50Hz and up, both set-ups sounded very similar. It was the lower Hz. that made my mind up for me. Actually, the WAF put her foot down and made my mind up for me. She did not like the furniture arrangement results with the two MBM's up front. :o

Bill,

Yes I did. I was able to easily run a xo of 120Hz. I tried it for awhile, but did not like the localization I was getting from the nearfield main sub. In addition, I was able to get some good room gain in the low end by placing the main sub in the front right corner. From 50Hz and up, both set-ups sounded very similar. It was the lower Hz. that made my mind up for me. Actually, the WAF put her foot down and made my mind up for me. She did not like the furniture arrangement results with the two MBM's up front. :o

Oh yeh, they do get in the way don't they.

Bill

Localization will be a problem, simply because your mains aren't stout enough, in terms of both output and extension. It's not the subwoofers that stick out, but the fact that the mains are compressing and the subs are picking up their slack.

I run my subwoofers up to 120Hz or maybe even a bit higher, but I also run my mains full range. The result is a single, coherent soundfield.

Localization will be a problem, simply because your mains aren't stout enough, in terms of both output and extension. It's not the subwoofers that stick out, but the fact that the mains are compressing and the subs are picking up their slack.

I run my subwoofers up to 120Hz or maybe even a bit higher, but I also run my mains full range. The result is a single, coherent soundfield.

So you do the LFE+MAIN setting in the AVR.

Localization will be a problem, simply because your mains aren't stout enough, in terms of both output and extension. It's not the subwoofers that stick out, but the fact that the mains are compressing and the subs are picking up their slack.

I run my subwoofers up to 120Hz or maybe even a bit higher, but I also run my mains full range. The result is a single, coherent soundfield.

Do you have large mains that play low? I would think running the Mythos 4's that I have as "large" would probably not work as well, since they are not terribly "stout" at the low end (as you put it).

Localization will be a problem, simply because your mains aren't stout enough, in terms of both output and extension. It's not the subwoofers that stick out, but the fact that the mains are compressing and the subs are picking up their slack.

I run my subwoofers up to 120Hz or maybe even a bit higher, but I also run my mains full range. The result is a single, coherent soundfield.

Tried that and didn't care for it as much as mains being "small". I have Polk monitor 10's (crossovers have been updated and tweeter is peerless) and I get more detail on the top end with a small setting.

Bill

So you do the LFE+MAIN setting in the AVR.

Yes. (AVR is a Denon 4306.)

Do you have large mains that play low? I would think running the Mythos 4's that I have as "large" would probably not work as well, since they are not terribly "stout" at the low end (as you put it).

My mains are Tannoy 12" Dual Concentrics in sealed boxes with solid in-room extension down into the high-40Hz range, so most people would consider them "large" and I consider them to play reasonably low.

My point was that localization is always going to be an issue with such small mains. The solution is not to kvetch about subwoofer crossover frequency, but to upgrade the mains.

Tried that and didn't care for it as much as mains being "small". I have Polk monitor 10's (crossovers have been updated and tweeter is peerless) and I get more detail on the top end with a small setting.

Not a big shock, considering those have fairly skimpy cone area (IIRC, two 6.5" midwoofers with a ~10" PR right) and a wooly bass tuning.

You could go the Behringer DCX2496 (loudspeaker management crossover system) route where you’ll have an assorted use of crossover filters to tailor the LCRS and LFE.1 with any desirable setting within its capability operating performance range.

Yes. (AVR is a Denon 4306.)



My mains are Tannoy 12" Dual Concentrics in sealed boxes with solid in-room extension down into the high-40Hz range, so most people would consider them "large" and I consider them to play reasonably low.

My point was that localization is always going to be an issue with such small mains. The solution is not to kvetch about subwoofer crossover frequency, but to upgrade the mains.



Not a big shock, considering those have fairly skimpy cone area (IIRC, two 6.5" midwoofers with a ~10" PR right) and a wooly bass tuning.

Yes, but I also have dual MBM's (one with each main) handling the 50 hz up on the LFE. Raising the LFE crossover to 150 doesn't make a big change in the audio.

Bill

Its cut-off range is 120Hz for the (LFE.1 track) the remaining other channels can be costumed tailored with DCX2496 to have low pass cut-off at any range.

So unless you have (bass manger) you could I guess turn the level up on the sub bass to 160Hz, but the (bass manger) would have prefixed setting of 80Hz or what ever the manufacture has implemented into there product so it wouldn’t make much difference.

Get a DCX2496 then you can start playing around with crossover frequency cut-offs.

Its cut-off range is 120Hz for the (LFE.1 track) the remaining other channels can be costumed tailored with DCX2496 to have low pass cut-off at any range.

So unless you have (bass manger) you could I guess turn the level up on the sub bass to 160Hz, but the (bass manger) would have prefixed setting of 80Hz or what ever the manufacture has implemented into there product so it wouldn’t make much difference.

Get a DCX2496 then you can start playing around with crossover frequency cut-offs.

If you are addressing me, I have a Anti Mode 8033B installed on the LFE line along with a Paradigm X-30 volume controller.

Bill

If you are addressing me, I have a Anti Mode 8033B installed on the LFE line along with a Paradigm X-30 volume controller.

Bill

Oh, I see this device I was looking at that last year I think, can’t remember where, fascinating device. Just being doing some research I see there’s some discussion on it, hmmm.

http://homepage.ntlworld.com/john.mulcahy/roomeq/images/8033/8033front.jpg

http://homepage.ntlworld.com/john.mulcahy/roomeq/images/8033/8033rear.jpg

http://www.hometheatershack.com/forums/bfd-forum/11699-testing-dspeaker-anti-mode-8033-a.html

http://verkkokauppa.planeetta.net/epages/Planeetta.sf/en_GB/?ObjectPath=/Shops/vlsi/Products/8033B/SubProducts/8033B-0001

This is the correction that my 8033 applies in my room...

http://im1.shutterfly.com/media/47b8cf03b3127ccec5f85e78256400000040O00AbtmTFo3YsWIPbz4M/cC/f%3D0/ps%3D50/r%3D0/rx%3D720/ry%3D480/

http://im1.shutterfly.com/media/47b8cf03b3127ccec5f82749e4c100000040O00AbtmTFo3YsWIPbz4M/cC/f%3D0/ps%3D50/r%3D0/rx%3D720/ry%3D480/