Hsu MBM-12 Thread

[HP666]

Can we discuss the mid bss moduel from Hsu.

Are you thinking about buying one? Why?
If you own one already:
Why did you buy it?
Where did you place it?
What equipment are you using it with?
How did it integrate?
Settings?
How did everything sound before?
And now?

 

[Sheep]

No.

You can get the same performance with normal subwoofers, you don't need a separate 12inch midbass accelerator.

SheepStar

 

[gene]

No.

You can get the same performance with normal subwoofers, you don't need a separate 12inch midbass accelerator.

SheepStar

It is kinda a "unique" product that I am not sure I fully understand yet. All I can gather is they are using the bandwidth limited sub for higher frequency modal control but I could be wrong. We will eventually arrange for a review when we get caught up on other projects.

 

[Tdekany]

No.

You can get the same performance with normal subwoofers, you don't need a separate 12inch midbass accelerator.

SheepStar

Who knew Dr Hsu was wrong.

 

[mike c]

would an extra subwoofer with an external high and low crossover have the same effect?

 

[Peter Marcks]

That's a great question, what are the benefits of MBM-12 that one cannot get from simply using another true subwoofer?

By using an ultra-light cone woofer with very high sensitivity in the mid-bass region, in addition to an enclosure specifically designed for mid-bass use, the MBM-12 has much higher mid-bass headroom and better frequency response linearity vs most true subwoofers. For comparison purposes, a 350w RMS MBM-12 with a relatively low excursion 12" woofer has +10db higher headroom in the mid-bass than the VTF-3 HO. That is higher headroom in that region than three VTF-3 HO's with 1500w RMS power, and triple 12" drivers ($2700 too).

So improved headroom and linearity in the mid/upper bass is one benefit. Another benefit would be wider dynamic range, since the true subwoofer would be relieved from mid-bass duties. There would also be lower intermodulation distortion, since the mid-bass can no longer be modulated by the lower bass. Finally, and possibly even most importantly, one is able to utilize nearfield mid-bass (next to the couch) and farfield low bass (front left or right corner) to reproduce bass in the locations that tend to be most suited for these ranges. Nearfield placement of mid-bass will give great impact and lower distortion for a given input level (due to close proximity to the listening position), while farfield placement of true subwoofer will help to smooth out frequency response while avoiding the dips in frequency response that can result from using a true subwoofer placed nearfield in rooms that are not super deep. Placing a true subwoofer in the nearfield can also provide great impact, but in most rooms there will be cancellation as one pressure wave moves forward and reflects backwards as the next pressure wave moves forward. This is avoided with nearfield mid-bass/farfield low-bass setup.

You all may now carry on with the discussion, now that you have some insight into why this idea came into play from us

Sincerely,

 

[Sheep]

That's a great question, what are the benefits of MBM-12 that one cannot get from simply using another true subwoofer?

By using an ultra-light cone woofer with very high sensitivity in the mid-bass region, in addition to an enclosure specifically designed for mid-bass use, the MBM-12 has much higher mid-bass headroom and better frequency response linearity vs most true subwoofers. For comparison purposes, a 350w RMS MBM-12 with a relatively low excursion 12" woofer has +10db higher headroom in the mid-bass than the VTF-3 HO. That is higher headroom in that region than three VTF-3 HO's with 1500w RMS power, and triple 12" drivers ($2700 too).

So improved headroom and linearity in the mid/upper bass is one benefit. Another benefit would be wider dynamic range, since the true subwoofer would be relieved from mid-bass duties. There would also be lower intermodulation distortion, since the mid-bass can no longer be modulated by the lower bass. Finally, and possibly even most importantly, one is able to utilize nearfield mid-bass (next to the couch) and farfield low bass (front left or right corner) to reproduce bass in the locations that tend to be most suited for these ranges. Nearfield placement of mid-bass will give great impact and lower distortion for a given input level (due to close proximity to the listening position), while farfield placement of true subwoofer will help to smooth out frequency response while avoiding the dips in frequency response that can result from using a true subwoofer placed nearfield in rooms that are not super deep. Placing a true subwoofer in the nearfield can also provide great impact, but in most rooms there will be cancellation as one pressure wave moves forward and reflects backwards as the next pressure wave moves forward. This is avoided with nearfield mid-bass/farfield low-bass setup.

You all may now carry on with the discussion, now that you have some insight into why this idea came into play from us

Sincerely,

Couple Questions...

1.) Is the distortion lowered enough for it to be audible?
2.) Is the extra headroom really necessary when current subwoofers can hit over 110dBs in that region anyway?
3.) Does the MBM-12 become localizable? Can it be placed in out-of-sight spots?
4.) Given the cost of a MBM-12 and a separate subwoofer, will it outperform ANY other subwoofer (DIY or Retail) at the same price point?

TC Sounds is releasing their own line of subwoofers for home usage featuring the LMS-5400 driver. This driver is only available in 15 or 18inches and has 32mm of Xmax (one way)! Starting prices are below 1 grand.

From TC Sounds...

Now it’s time for us to show off what we can do with our own ingenuity, experience and creativity. We’ve assembled a world class team of engineering talent and are proud to announce the birth of a whole new line of subwoofers that are expected to not only outperform everything that comes before them in their respective categories, but offer features and functions that have never before been included in commercially available powered subwoofer systems!

Leading the pack and appropriately nicknamed theBeast, the twin LHT-5400 behemoth offers the most excursion, most displacement, highest low frequency output and most power of any commercially available transducer driven subwoofer system in the world. Period.

On the driver side of things, let’s just say nothing in the realm of home audio can come close to a single LHT -5400. With a true 4” diameter titanium former overhung linear voice coil, providing a BL curve flat to within 2% over the entire travel used, proprietary patent pending technology that virtually eliminates inductive rise and the resultant motor non linearity’s associated with it, a revolutionary motor boasting more FEA time than most people spend working in a month refining the circuit – we could go on and on.. Suffice it to say – we’ve completely gone overboard for this system. There is not a single transducer available in any commercially available home theater subwoofer with the raw output, vanishingly low compression, dynamic capability, and incredibly low distortion as this driver. We’ve pulled out all the stops on the LHT 5400. Yes we just said NOT ONE commercially available subwoofer available has a transducer that approaches capabilities of this driver, and in the full system – we employ four of these behemoths with 18" diameters ... Yes four!

You might think that means it will cost four times as much as the nearest available Hi End competitor? Quite the opposite is the case in fact! Considering the competition it completely KNOCKS to the floor - it will be surprisingly competitively priced.

In other news is, theBeast is not alone! It has a plethora of smaller cousins which are expected set new standards across the price spectrum starting below $1000 US dollars. Watch this space for detailed specifications, reviews, and expected delivery dates for the new TC Sounds home theater lineup.

SheepStar

 

[Matt34]

would an extra subwoofer with an external high and low crossover have the same effect?

Mike,

It's possible but the woofer in the MBM is specifically designed to be used in the 50-100hz range. I believe this unit would best serve those that don't have true full range mains.

There is a guy running two SVS20-39PC+ along with a BagEnd Infrasub 18 and he felt it was fairly easy to dial it in. With it near field you could adjust it accordingly to your source(music or movies).

Sheep,

2.) Is the extra headroom really necessary when current subwoofers can hit over 110dBs in that region anyway?

This was Dreamcatcher's response to the same question:

Being capable is one thing...
Most subwoofers don't really do 60hz and up well (musical). The JL Audio f113 is not most subwoofers, but is the only sub I've owned that sounds musical through it's entire frequency range.
On the other side most main speakers (even most full range speakers) don't do well (hit hard) below 100hz. Can they play below 100hz, yes, but can they hit 110+db at say 80hz, I doubt it. And do you really want them to? I don't know about you but I cringe a bit every time a bomb goes off and I'm listening close to reference level. I wonder how many of those can that 6.5" woofer take.


With that being said, I'm going to give it a try when I get back. If it doesn't work out I'll return it.

Unless of course, Audioholics get their hands on one first and does a review.

 

[mike c]

thanks matt, I wish somebody would A/B an MBM vs. a subwoofer with an external crossover and see if the MBM really does thing's better. (hint hint AH)

 

[Matt34]

TC Sounds is releasing their own line of subwoofers for home usage featuring the LMS-5400 driver. This driver is only available in 15 or 18inches and has 32mm of Xmax (one way)! Starting prices are below 1 grand.

SheepStar

Oh my, haven't heard about this! Should be interesting to see what the under $1000 offering will be.

 

[Matt34]

Here is a SMS-1 reading(no EQ) of Dreamcatcher's mains (NHT M6s) and VTF3-HO only.

This one includes the MBM-12(no EQ).

Just the NHT's no subs.

 

[Tomorrow]

Couple Questions...

1.) Is the distortion lowered enough for it to be audible?
2.) Is the extra headroom really necessary when current subwoofers can hit over 110dBs in that region anyway?
3.) Does the MBM-12 become localizable? Can it be placed in out-of-sight spots?
4.) Given the cost of a MBM-12 and a separate subwoofer, will it outperform ANY other subwoofer (DIY or Retail) at the same price point?

TC Sounds is releasing their own line of subwoofers for home usage featuring the LMS-5400 driver. This driver is only available in 15 or 18inches and has 32mm of Xmax (one way)! Starting prices are below 1 grand.

From TC Sounds...

SheepStar

I'll be sure to have my wife help me move that 400+ lb. LMS-5400 into it's proper location.

 

[AVRat]

There is a guy running two SVS20-39PC+ along with a BagEnd Infrasub 18 and he felt it was fairly easy to dial it in.

Just curious, do you remember who has this setup. Like to check it out.

 

[Matt34]

Just curious, do you remember who has this setup. Like to check it out.

Without looking I think his screen name was Shully on AVSforums.

Ok I looked, it's shelly.

 

[Sheep]

I'll be sure to have my wife help me move that 400+ lb. LMS-5400 into it's proper location.

Well, theres always Bose. I hear their stuff is light.

SheepStar

 

[majorloser]

Ok, it's February now and I'm back from all my fun travelling.

That means it's time to look at an MBM-12
I planned on trying out an MBM-12 in my room since both Peter and Dr. Hsu suggested one. Besides, I still have to work out that SVS PB-12 Ultra/2 comparison with another member.

I can add that to my wish list of toys along with a Behringer Feedback Destroyer.

 

[Peter Marcks]

Dear Sheep,

1.) Is the distortion lowered enough for it to be audible?

I think so. Nearfield placement is nice not only for lower distortion for a given input level, but also higher impact too.

2.) Is the extra headroom really necessary when current subwoofers can hit over 110dBs in that region anyway?

Absolutely! The difference between using most true subwoofers placed up front in a corner to handle mid-bass and deep bass vs. using the mid-bass module placed next to the listening position is like night and day.

3.) Does the MBM-12 become localizable? Can it be placed in out-of-sight spots?

As long as the MBM-12 is crossed over below about 90Hz, it should not be localizeable. Some people even run it crossed over a bit higher without any big issues for them. The best place to keep the MBM out of sight is to place it sideways behind the couch. That is a great location for the unit.

4.) Given the cost of a MBM-12 and a separate subwoofer, will it outperform ANY other subwoofer (DIY or Retail) at the same price point?

I suppose this depends on what definition of performance we are talking about. The MBM-based system would most likely have the advantage in wider dynamic range, higher maximum output capability before the onset of compression, higher mid-bass headroom, flatter and more linear mid/upper bass response, lower intermodulation distortion. However, the deep bass capability below 50Hz will be dependent on the true subwoofer of course.

 

[abboudc]

Ok, it's February now and I'm back from all my fun travelling.

That means it's time to look at an MBM-12
I planned on trying out an MBM-12 in my room since both Peter and Dr. Hsu suggested one. Besides, I still have to work out that SVS PB-12 Ultra/2 comparison with another member.

I can add that to my wish list of toys along with a Behringer Feedback Destroyer.

When can we expect a review?

 

[gene]

Peter;

I am curious, if one had a subwoofer that was linear beyond its 80Hz crossover point, and placed 2 or 4 of them in the room to smooth out bass response, do you think the MBM product would still be needed?

I have found it beneficial to set Satellite speakers to full range (assuming they could handle it), in certain installations, even though I was using mutliple subs in the room because it did in fact smooth out the bass response at and slighlty above the crossover point of the subs.

If you get a momemt, check out my RBH T-30LSE review where I go into detail on it.

http://www.audioholics.com/productreviews/loudspeakers/RBHSignatureT30LSEp1.php

 

[Peter Marcks]

Gene, with that many subwoofers, it may not be needed, especially with four subwoofers! The main benefits in using the MBM-12 (or multiples of them) and letting the true subwoofers handle 50Hz and below with that system would be for even lower IM distortion and even wider dynamic range, but then again we're talking about something way overkill here