Will the HSU MBM work with any sub?

[JEFFREY GTS]

I just took the plunge on the SVS PB-12 NSD and am thrilled. I know it produces some very low bass. I am also concerned with the upper bass frequencies as well and see that HSU has a product that is supposed to cover that area. I was wondering how well it would work together with the SVS. Or is it specifically designed to work with HSU subs? That brings me to my next question. Would I be able to buy a PB-10 NSD and have that crossed over higher to get some more punch in the upper bass region?

[vitod]

According the HSU, the MBM is crossed to take FQ of 50hz-150hz and will work with any sub. The PB10 will do the upper region but will go down to 20hz and lower.......hey that's good!

[bfdtv]

I was wondering how well it would work together with the SVS.

Yes, it will.

The PB12 drops off substantially after around 90Hz, so you should see a significant improvement with the addition of a MBM-12.

Would I be able to buy a PB-10 NSD and have that crossed over higher to get some more punch in the upper bass region?

The PB10 and PB12 are both tuned to maximize their extension. They won't offer comparable output or response at higher frequencies relative to a woofer tuned specifically for mid-bass reproduction.

[jedi.night]

agreed,

I'm going to pair an MBM-12 with a SVS PC ULTRA.

Should get the MBM next week.

Will report back with what I find.

[JEFFREY GTS]

Originally Posted by jedi.night

agreed,

I'm going to pair an MBM-12 with a SVS PC ULTRA.

Should get the MBM next week.

Will report back with what I find.

I am very interested in the outcome of the MBM.

[cschang]

Originally Posted by vitod

According the HSU, the MBM is crossed to take FQ of 50hz-150hz and will work with any sub. The PB10 will do the upper region but will go down to 20hz and lower.......hey that's good!

But it is the sound quality in that region that should be compared, not just the fact that they both play it.

[JEFFREY GTS]

Also, talking with HSU, they recommended that I place it next to the couch. That is not an option for me. The only place I can put it is on top of my current SVS PB12 NSD. Will it defeat the purpose or will it be okay sitting on top of my other sub?

[jedi.night]

Originally Posted by JEFFREY GTS

Also, talking with HSU, they recommended that I place it next to the couch. That is not an option for me. The only place I can put it is on top of my current SVS PB12 NSD. Will it defeat the purpose or will it be okay sitting on top of my other sub?

From what I've read that wouldn't be a problem. The only downfall is that you loose the punch that you would get from having it near field.

HSU recommends that the MBM be placed near field and the true Sub to be far field.
These are not set in stone. Dr. Hsu has stated that you can place the MBM between the mains or next to the True Sub.

If you have smaller sat's that don't go down below 80hz, then you have a dilemma or rather a choice of placing the MBM near field and risk localization (which depends on your taste, hearing a slight directionality from it doesn't bother me at all). Purists won't want to be able to localize the bass at all. ( reason being you would set the crossover higher than 80hz, most likely 100hz or 120hz to pair well with small sats.)


I'm running the MBM with a PC-Ultra and an Orb 5 speaker setup.
I'm crossing the MBM at 120hz (the orbs can be crossed at 80hz, but I'm going to give it a try at 120hz for a few days, 100hz and then 80hz.
The PC-Ultra in all cases will be handling 50hz on down, set in 16hz tune.
The beauty of the MBM is that it frees up some power on the Ultra since it will only be receiving the very Low LFE. Seems like it has even more punch now even though it had plenty of to spare even before introducing the MBM-12.

I have placed the MBM 12 behind the back left side ( if your back is facing the couch). It's a few feet from a corner in the room, my couch is a half circle shape.
The MBM port is facing away from the couch and towards the corner wall.

So far, I'm very impressed with the MBM and PC-Ultra combo. I haven't truly calibrated it yet with an SPL meter but I will in a week or so.
Just had to play with the gain on the MBM a bit, it's very sensitive and it does play the Mid-range loud if turned up to far. I only have it set just under 10 O'clock and it sounds great with a nice little rumble through the couch.
Crossed at 120hz, it is slightly locatable to my ears, but not enough to really bother me at all.
I will play with it some more and try lower crossovers and report back my opinions.

[cschang]

You should try and cross the Orbs even higher....they begin to roll off before 150hz. If you cross at 80hz, you will be missing a lot of information...localized or not.

[bfdtv]

I agree with curtis.

I would try setting your receiver to 140Hz or 160Hz and move the MBM-12 closer to the Orbs, if possible, so frequencies from 100-160Hz sound like they are coming from the speakers rather than the MBM.

[DreamCatcher]

Originally Posted by jedi.night

From what I've read that wouldn't be a problem. The only downfall is that you loose the punch that you would get from having it near field.

HSU recommends that the MBM be placed near field and the true Sub to be far field.
These are not set in stone. Dr. Hsu has stated that you can place the MBM between the mains or next to the True Sub.

If you have smaller sat's that don't go down below 80hz, then you have a dilemma or rather a choice of placing the MBM near field and risk localization (which depends on your taste, hearing a slight directionality from it doesn't bother me at all). Purists won't want to be able to localize the bass at all. ( reason being you would set the crossover higher than 80hz, most likely 100hz or 120hz to pair well with small sats.)


I'm running the MBM with a PC-Ultra and an Orb 5 speaker setup.
I'm crossing the MBM at 120hz (the orbs can be crossed at 80hz, but I'm going to give it a try at 120hz for a few days, 100hz and then 80hz.
The PC-Ultra in all cases will be handling 50hz on down, set in 16hz tune.
The beauty of the MBM is that it frees up some power on the Ultra since it will only be receiving the very Low LFE. Seems like it has even more punch now even though it had plenty of to spare even before introducing the MBM-12.

I have placed the MBM 12 behind the back left side ( if your back is facing the couch). It's a few feet from a corner in the room, my couch is a half circle shape.
The MBM port is facing away from the couch and towards the corner wall.

So far, I'm very impressed with the MBM and PC-Ultra combo. I haven't truly calibrated it yet with an SPL meter but I will in a week or so.
Just had to play with the gain on the MBM a bit, it's very sensitive and it does play the Mid-range loud if turned up to far. I only have it set just under 10 O'clock and it sounds great with a nice little rumble through the couch.
Crossed at 120hz, it is slightly locatable to my ears, but not enough to really bother me at all.
I will play with it some more and try lower crossovers and report back my opinions.

Balancing the MBM-12 w/ your Ultra and with your mains is crucial!
When I first got the MBM-12 in my system with the 3HO Turbo, the mid-bass (MBM-12) was very localizable and sounded like crap. My first thought was, "this thing is going back to HSU"! It took me a couple hours of tweaking on the gain of each sub, processor and sub crossovers, and using the Velo SMS-1, to get the MBM-12 to blend with my 3HO sub/mains and listening room. My mains start rolling off around 60hz (the NHT M6s), but I've found crossing them over to the MBM-12 at around 85-110hz works best for my system. The MBM-12 has completely disappeared and I have it located right next to my main listening position.

Once you get the MBM-12 dialed in, the rewards are huge!
Mid-bass detail and slam have never sounded this good in my system!

dc

[bfdtv]

DreamCatcher,

How much would you say the SMS-1 helped in mating the MBM-12 with the 3HO in your room? Could you have done it without the SMS-1 with a bit more effort?

[DreamCatcher]

Originally Posted by bfdtv

DreamCatcher,

How much would you say the SMS-1 helped in mating the MBM-12 with the 3HO in your room? Could you have done it without the SMS-1 with a bit more effort?

The SMS-1 is a great tool for getting the subs balanced but not essential.
A SPL meter and a bit of tweaking should give similar results.

dc

[SteveCallas]

The PB12 drops off substantially after around 90Hz, so you should see a significant improvement with the addition of a MBM-12.

Umm, you do realize that most speakers cross over to subs at 80hz, yes? The FR of his sub above 90hz is insignificant. This MBM unit would only serve a purpose if you have small bookshelves that can't hold their own to the crossover frequency.

The PB10 and PB12 are both tuned to maximize their extension. They won't offer comparable output or response at higher frequencies relative to a woofer tuned specifically for mid-bass reproduction.

What you are advocating is compression. I haven't seen any measurements of the PB12, but I have seen them on the PB10, and it is more than capable around the crossover region.

But it is the sound quality in that region that should be compared, not just the fact that they both play it.

Yes, and tossing two additional filters into the mix - with their high probability for degraded transient response and low probability for nailing a flat FR - make it difficult to imagine it would sound better than a sub that can naturally handle its own in that region. I remember getting into a lengthy discussion about this product a while back.....well now we can finally see some actual in room results. Who's willing to post in room measurements with this unit in the chain? From the seat, take a sweep of each unit individually - speakers, MBM, and sub, then one with them all in play.

I contend that the better option is to get a second sub.

[Richard Mayer]

Originally Posted by SteveCallas

Umm, you do realize that most speakers cross over to subs at 80hz, yes? The FR of his sub above 90hz is insignificant. This MBM unit would only serve a purpose if you have small bookshelves that can't hold their own to the crossover frequency.

I wouldn't say that. For example the PB10 is capable of 100-105 dB levels in 50-100 Hz while the MBM-12 should do 110-115 dB. Higher headroom means better dynamics and lower distortion.

[SteveCallas]

But then I ask again, just as I did before, what is the point of greater dynamics and decreased distortion in a small bass range? Were you to buy a second identical subwoofer, you'd gain better dynamics and decreased distortion over the whole sub range - you'd also have a much easier time integrating it than you would a superwoofer. A logical goal would be to have a system that roughly maintains a given level of capability over all frequencies, not just bits and pieces.

[cschang]

Originally Posted by SteveCallas

But then I ask again, just as I did before, what is the point of greater dynamics and decreased distortion in a small bass range? Were you to buy a second identical subwoofer, you'd gain better dynamics and decreased distortion over the whole sub range - you'd also have a much easier time integrating it than you would a superwoofer. A logical goal would be to have a system that roughly maintains a given level of capability over all frequencies, not just bits and pieces.

Very good arguments, but also remember you also do not get a driver/sub specifically designed for 50hz on up, ease of use in nearfield placement(size), and cost.

Like you said, all speculation until experienced in practice.

[cyberbri]

My take is that it's like adding shakers. You put it near field (if possible) and the mid-bass gives you that kick while letting the main sub do the deeper stuff. Some of the larger subs already are for this purpose, and there are already people who let their big, big subs handle say below 30~40Hz down to 10~25Hz or so, with other subs handling the more audible bass.

[SteveCallas]

driver/sub specifically designed for 50hz on up

On up to what though? 80hz? 150hz? Subwoofers ARE specifically designed to handle up to 80hz....going down deep is the added bonus, not the other way around. If the mains aren't capable to 100hz or 80hz, then yeah, a superwoofer is a legitimate solution.

[cschang]

I believe on up to 150hz.

What kind of headroom do mains have below 150hz?

[JEFFREY GTS]

In regards to the placement of the MBM, I was told that that the optimum placement is near your seating position. And was told NOT to set it on top of your current sub, would the opposite left corner be okay?

[Richard Mayer]

Originally Posted by SteveCallas

But then I ask again, just as I did before, what is the point of greater dynamics and decreased distortion in a small bass range? Were you to buy a second identical subwoofer, you'd gain better dynamics and decreased distortion over the whole sub range - you'd also have a much easier time integrating it than you would a superwoofer. A logical goal would be to have a system that roughly maintains a given level of capability over all frequencies, not just bits and pieces.

Sure, second sub would be better, but I think that's not what HSU is trying to accomplish with the MBM-12. It was meant as a relatively cheap and small upgrade for your current system/sub. Let's wait what people think about it before crushing it...

[SteveCallas]

I'm not crushing it, I just think it has a very specific, limited use.

What kind of headroom do mains have below 150hz?

Depends on your mains. Most three ways don't cross over to the woofer(s) until 200-400hz.

[ggunnell]

In Colin Miller and Brian Florians' excellent article Miscellaneous Ramblings on Subwoofer Crossover Frequencies:

http://www.hometheaterhifi.com/volum...rs-9-2002.html

They mention 120Hz brickwalled as the top end of frequencies mixed to the LFE out.

Does anyone know the actual upper limit of LFE channel mix in commercial recordings?

[SteveCallas]

Unless I'm misunderstanding, you just answered your own question. The upper limit is 120hz.

[rockemsockem]

I wonder how two of these set under my bookshelf mains as bass bins would sound?

[jedi.night]

Originally Posted by cschang

You should try and cross the Orbs even higher....they begin to roll off before 150hz. If you cross at 80hz, you will be missing a lot of information...localized or not.

Well, I decided to bust out the SPL meter to see just how far down the orbs go.

They don't really drop off until about 90hz, at least significantly.
But the problem is I have a MOD 2 center and that has a higher drop around 120hz and then goes back to normal and begins to drop off at around 90hz.
Weird, i expected it to peform better in the lower mid bass region, but it could be room acoustics.
Remember that the room is having an effect on the roll off of these orbs.

I don't think I will cross the MBM any lower than 120hz because of the inconsistency of my Center Orb.

I still have it place nearfield behind the couch.


I think steve has a point to a degree, This MBM is great for someone in my position with orbs.

I might try it in the front of the room under my Plasma TV. The orbs are above the TV. So it would be center under the center channel. And about 6 feet to the right of the PC-Ultra.

I will see how this sounds. Although I do enjoy the Punch I get from behind the couch. But like I said before, I have to keep the gain low, around 9am or it's too localizable.

I do like to run a nice house curve with my low end boosted.

I usually listen at around -20 on my HK, this is about 66dbs. So I often run the Ultra hot, at around 76-80 dbs.

[Peter Marcks]

The argument that the MBM only serves a purpose with bookshelf speakers is a fallacy in my opinion. The reality is that there are few loudspeakers that have the mid-bass headroom to match the MBM-12, let alone anything near $400. And even then, these loudspeakers don't get the benefit of being placed nearfield for reduced interaction with room.

The term "good enough" can mean almost anything. Some people may find it good enough to have about 105db at the listening position without output compression in the 50-100Hz region. The MBM-12 will give >120db at the listening position with virtually no output compression in this same range of frequencies. That is a huge difference no matter which way you look at it. Even a difference of 6-10db would be huge. Is that a limited range of frequencies? I don't think so. Looking at various waterfall charts that are floating around the internet, it seems that almost every movie has lots of activity and some very large dynamic peaks in the 50-80Hz mid-bass region. Also, obviously music is rich with information in this range of frequencies, while much less rich in content below about 25Hz.

A setup with dual VTF-3 HO + turbochargers would stand to seriously gain from a single MBM-12, which sells for a fraction of the cost of a single one of these subwoofers. A system with single VTF-3 HO + MBM-12 can do things that no quantity of VTF-3 HO's or other true subwoofers placed farfield in a corner handling the low/mid/upper bass can do, namely having a very high ratio of direct-to-reflected sound energy in the mid bass region for reduced room effects, in addition to having vanishing levels of intermodulation distortion between low and mid bass since the mid bass frequencies can no longer be modulated by the lower bass frequencies.

There's no doubt that adding a second true subwoofer will generally make a very large and noticeable improvement in performance, but it is certainly no substitute for the MBM.

[Peter Marcks]

Originally Posted by jedi.night

From what I've read that wouldn't be a problem. The only downfall is that you loose the punch that you would get from having it near field.

HSU recommends that the MBM be placed near field and the true Sub to be far field.
These are not set in stone. Dr. Hsu has stated that you can place the MBM between the mains or next to the True Sub.

If you have smaller sat's that don't go down below 80hz, then you have a dilemma or rather a choice of placing the MBM near field and risk localization (which depends on your taste, hearing a slight directionality from it doesn't bother me at all). Purists won't want to be able to localize the bass at all. ( reason being you would set the crossover higher than 80hz, most likely 100hz or 120hz to pair well with small sats.)


I'm running the MBM with a PC-Ultra and an Orb 5 speaker setup.
I'm crossing the MBM at 120hz (the orbs can be crossed at 80hz, but I'm going to give it a try at 120hz for a few days, 100hz and then 80hz.
The PC-Ultra in all cases will be handling 50hz on down, set in 16hz tune.
The beauty of the MBM is that it frees up some power on the Ultra since it will only be receiving the very Low LFE. Seems like it has even more punch now even though it had plenty of to spare even before introducing the MBM-12.

I have placed the MBM 12 behind the back left side ( if your back is facing the couch). It's a few feet from a corner in the room, my couch is a half circle shape.
The MBM port is facing away from the couch and towards the corner wall.

So far, I'm very impressed with the MBM and PC-Ultra combo. I haven't truly calibrated it yet with an SPL meter but I will in a week or so.
Just had to play with the gain on the MBM a bit, it's very sensitive and it does play the Mid-range loud if turned up to far. I only have it set just under 10 O'clock and it sounds great with a nice little rumble through the couch.
Crossed at 120hz, it is slightly locatable to my ears, but not enough to really bother me at all.
I will play with it some more and try lower crossovers and report back my opinions.

I am very happy to hear that you have noticed an improvement in sound quality, jedi!

Would you say that the MBM-12 has [directly or indirectly] improved the sound quality of your system at all bass frequencies?

Thanks again

[Peter Marcks]

Originally Posted by DreamCatcher

Once you get the MBM-12 dialed in, the rewards are huge!
Mid-bass detail and slam have never sounded this good in my system!

dc

That's what I predicted would happen, dc!!!

May I ask what other subwoofers you have tried in your home?

I am definitely humbled by the glowing remarks.

Sincerely,