S

Sylar

Full Audioholic
I have bumped into the mid bass module numerous times before. I have only come across the HSU one so far.

When does one go for this? Is this placement sensitive?
 
j_garcia

j_garcia

Audioholic Jedi
You've only bumped into one because they are the only ones who make one that I've ever heard of.

Anything above 120Hz is localizable, so if it is playing above that, which I believe it is, yes it will be placement sensitive. Essentially, all speakers are placement sensitive.
 
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shadyJ

Speaker of the House
Staff member
Certain rooms have bass suckouts in certain frequencies, sometimes people can have a 10 to 15 db null in important bass frequencies like 50 or 60 hz. The MBM can give you a boost at these frequencies. As for placement, Hsu usually recommends placing the MBM as close to the listening position as you can get.
 
bread29

bread29

Junior Audioholic
I have an MBM paired with the VTF-3. The MBM is placed directly behind the couch and is set only to cover 50-90hz, and the VTF-3 is crossed over to cover below 50hz material. The MBM definitely gives some extra oomph to gunshots and explosions.
 
j_garcia

j_garcia

Audioholic Jedi
AND... Bose makes one. Yup, I went there :D.
Technically, they call it a bass module :) I almost mentioned it too, but didn't feel like mentioning their name.

Certain rooms have bass suckouts in certain frequencies, sometimes people can have a 10 to 15 db null in important bass frequencies like 50 or 60 hz. The MBM can give you a boost at these frequencies. As for placement, Hsu usually recommends placing the MBM as close to the listening position as you can get.
Yes, there are situations where it might be a benefit, and you can't EQ a massive dip like that, however that is definitely a room issue. I would probably try treatments before buying something like the MBM. My previous room had a dip right at my 80Hz x-over with the sub I had at the time. Switched to a different sub and no longer had that problem.
 
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Sylar

Full Audioholic
Thats an expensive way to fix room issues. I wud rather try treatment and improve the acoustics, if I have issues and the money to spend :)

what's a cheap and easy way to find out/measure my room response
 
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jcl

Senior Audioholic
I was thinking of using the MBM to suppliment a Magnepan Center Channel when contemplating a surround sound maggie setup. It seemed like a better option than the icbm. Decided the maggies just didn't make sense so it never happened.
 
agarwalro

agarwalro

Audioholic Ninja
Certain rooms have bass suckouts in certain frequencies, sometimes people can have a 10 to 15 db null in important bass frequencies like 50 or 60 hz.
Poor placement and poor calibration result in suckouts. Period. Even the best sub or several off the best subs not corretly set up will have nulls. If the null happens to correspond with the listening position you get the "suckouts" effect.

MBM can give you a boost at these frequencies. As for placement, Hsu usually recommends placing the MBM as close to the listening position as you can get.
MBM is a way to say, this does not play deep enough to be a sub, but since you are reacting to our snake oil, here is the speaker you want but dont need.


I was thinking of using the MBM to suppliment a Magnepan Center Channel when contemplating a surround sound maggie setup. It seemed like a better option than the icbm. Decided the maggies just didn't make sense so it never happened.
Steps to resolve:
1) Forget about MBM (this is just a waste of money)
2) Crawl for bass and make sure your sub placement is not causing a mid bass null in the listening position
3) If placement and calibration for 1 sub alone does not completely resolve the issue, add a second subwoofer and set it up properly
 
Last edited:
gene

gene

Audioholics Master Chief
Administrator
It's usually NEVER a good idea to cross over subs at different frequencies in a room. To place a sub crossed over above 80Hz near a listening area is also unadvisable for reasons already mentioned in this thread. Just purchase two identical subs, properly place them and set them up and you will likely achieve much better results.

Here is a good guideline to get started:
http://www.audioholics.com/tweaks/get-good-bass/multiple-subwoofer-setup-calibration-1
 
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Sylar

Full Audioholic
It's usually NEVER a good idea to cross over subs at different frequencies in a room. To place a sub crossed over above 80Hz near a listening area is also unadvisable for reasons already mentioned in this thread. Just purchase two identical subs, properly place them and set them up and you will likely achieve much better results.

Here is a good guideline to get started:
http://www.audioholics.com/tweaks/get-good-bass/multiple-subwoofer-setup-calibration-1
Can I use REW and a mike instead? (Audyssey Mike from the AVR?)
 
lsiberian

lsiberian

Audioholic Overlord
Thats an expensive way to fix room issues. I wud rather try treatment and improve the acoustics, if I have issues and the money to spend :)

what's a cheap and easy way to find out/measure my room response
The frequencies we are talking about would require taking out walls and ceilings to fix. You can't normally treat out issues that low, but your ears also don't notice them as much. 2 properly setup subs are the best solution.
 
J

jcl

Senior Audioholic
The Magnepan center channel speakers start to roll off pretty high some as high as 200hz by their spec. I think the one i was looking at were rated at 160. They themselves have finally started to offer a bass module that acts as a stand and supplements the bass *of the center channel.* If you send something this high to a sub your ears will easily locate it. I have a BA system where the center needs to be crossed over high, and it is disturbing to hear voices coming from the sub instead of the center! So I knew I wanted to avoid this.

The idea was in the avr to set the crossover for the center channel at the same level as the front mains, say 80hz. Run the center out to an external crossover. Have the center speaker sitting on the MBM so they are co-located. Set the crossover so everything <160 goes to the mbm, everything >160 goes to the maggie center.
 
GranteedEV

GranteedEV

Audioholic Ninja
I'm not completely against a dissimilar subwoofer designed for a very specific passband, but you really need a convoluted setup to do it. It generally results in the "midbass module" being significantly lower in level than the other sub, and you really need two MBMs and one sub that can plumb the depths..
 

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