OFFICIAL Hsu MBM-12 thread - Page 2

Please mind the crudity of that picture. I have the sub right next to the computer stand. It's the only place asthetically it can go.

 

jason.pdf 222.111328125k . file

Jason, the first thing you should do is try to move your primary listening position away from the center of the room! With your current location for the recliner, you will experience a strong null from the room's standing waves.

The front left corner should be ok for the true subwoofer, with the MBM-12 sideways directly behind the couch. Just try to avoid sitting in the middle of the room, or placing any subwoofer there.

You would actually get better bass if you reoriented your setup with the TV and speakers/sub on the left wall.

Sincerely,

Reorienting my setup just won't work. And why is sitting in the middle of the room so poor? I figured that's the perfect place to sit. It's where I sit in movie theatres and such.

That's too bad, it would sound even better

The center of the room is where a strong null develops due to the physics involved with standing waves and how they interact in the midpoint of the room.

Movies:

Here is a good (but long) read on how waves setup in rooms and how various shapes of rooms effect the location of the waves.

http://www.harman.com/wp/pdf/Loudspeakers&RoomsPt3.pdf

In short, he concludes that no room shape can be called optimal, but you can orient your seat and your equipment to provide the best listening experience.

I would first calibrate your system to your listening position with an SPL or your receivers software (my Denon can very close to proper calibration on it's own without my SPL).

Then, with a constant test tone I would move around the room to make sure your listening position isn't in a local null (e.g. you might calibrate your position to 70 db and once you move the meter, the rest of the room might be at 90). You should also check you other seating positions.

You might then want to make minor adjustments in you seating positions or equipment to remove any null if it falls at or near your seating positions.

After that I think you will have done about as much as you could given your constraints.

Splotto

Why is it bad.....because your room is not a movie theater with TONS OF SPEAKERS, sound treatments, and tons of power, just to name a few...

We wouldn't steer you wrong...middle is the worst.....try putting your chair about 3 feet from the back wall..

Even if you could just move your chair back about 3ft, it may help.

Edit: Try out this spreadsheet. **Rename it to .xls instead of .txt first**

 

Copy of Room Mode Calculator.txt 175k . file

Jonny...I just dont get what the lines mean....what should I be looking for?

I believe the lines are sound levels at a given point from the reference wall. the valleys are where waves overlap to create a null.

Splotto

PS I received my MBM12 about a week ago and love it. I am still playing with locations but I can notice an impact without localization.

Splotto's got it really. The colored lines just graphically show you what the data in the upper portion of the sheet is telling you - that you have first order axial standing waves at the three frequencies in blue (for height, width, length), then second order (first harmonic of the first one) in black, then third, etc.

In layman's terms, using Movies2090's room, 9 feet from his back wall (1/2 room length) he has a null at 31Hz. Basically, precisely at the center, there will be nearly zero sound at 31Hz due to cancellation. Notice that the same thing is happening at the width midpoint at 35Hz...also right ontop of the recliner. So, that recliner position is really hurting for output in the low 30Hz area.

But, if he moves his chair back about 3 feet (just past the yellow 6 3/4'), he is no longer in the middle of that null. Now, then there's the 4th order null to worry about, so...pick your poison.

NOTE: Someone please fact check me here - I've been known to explain this stuff wrong or in a misleading manner But I think I've got it right...

I ordered two MBM-12's to play the "hard to reproduce" (and soooo sweet sounding) mid-bass SPL's to blend with my sub and mains/surrounds. I'm looking for full range, high-end fidelity reproduction that goes up in a linear relationship as I adjust the main volume.

Here's HSU (great support) recommendations: I can hook MBM-12's up several ways and am looking forward to playing with different ideas/placements.

1) Leave the RF-7 front main signals at full (large - I will experiment with small, too). Connect the MBM-12's to the L/R speaker leads next to the RF-7's. Set the LFE low pass to my sub around 40-60 Hz. Set the MBM-12's to 150 low pass. The Klipsch's and MBM-12's both blend to reproduce 50 to 150 Hz together. Below 50Hz goes to the sub. The RF-7's get the full main signals (unless the small setting sounds cleaner and fuller), and take it the rest of the way up.

2) LFE connection: MBM-12's and sub all connected to the LFE with high quality "Y" connection for the MBM-12's. The MBM-12's are going behind the couch or in left and right end table positions. Or, near the RF-7's ports. Using the LFE, set the MBM-12's crossover to about 80 and the sub's around 50 Hz. The RF-7's get the full L/R main signals. The sub handles 50 Hz and below, the MBM-s handle 50-80 Hz, and the RF-7's get the full main signals.

Crossover points and placement will be a major player on tuning.

With a 30 x 30 foot room, I have the Klipsch's spread out further than most DEMO rooms yet aimed towards a main listening sweet spot.

As a side note, on top of the RF-7's, I placed multi-directional tweeters. The tweeter cabinets aim two tweeters straight ahead, two at L/R 45 degree angles, and 2 at L/R 90 degree angles. I also have another pair of the multi-directional tweeters placed up high for lower volume fill.

When moving around the room, it sounds like a live sound stage. To my ears, it's linear and sweet, creating multiple sweet spots just like musicians hear playing live. That's just the way I want to hear recordings.

I was looking at new true subs and the journey began. Listening to musical instruments, I'd hear musical notes drop off both ABOVE and BELOW my sub's playing abilities. The best thing I did for my older 12 inch downfiring sub was to place it on a 18 inch table in a adjacent, closed off hall to my 30 x 30 foot listening room. HUGE musical difference in everyway. Then, I moved it right behind a RF-7's rear ports. The blend was immediately better throughout the entire soundstage.

I started looking for what I feel was the missing link - powered, real mid bass. Vandersteen Quad's and 5A's and others have powered mid-bass type components. Most studio monitors for mixing and recordng have separate built-in amps for both high and low drivers to get it right.

I like the open soundstage of the RF-7's immensely. I play piano, bass and guitar and I know how real musicians sound and musically blend acoustic and electric instruments together.

I'll experiment until the SPL's sound flat and even. I have an idea that any of the recommended set-up's from HSU, with my musician/new audiophile tweeking, is going to sound linear and clear as the main volume is adjusted.

My source is a OPPO 981, and Yamaha 7.1 RX-V2400 (125 x 7). The Yamaha has a sound stage optimizer mike to help me set-up balanced SPL's at all frequencies. To me, it's a nice combo for now. I may add a Rotel 1095 later (200 x 5) for headroom and use the Yamaha as a pre/processor. The powered MBM-12's may be the only upgrade I need for now.

Back to my budget 200 watt 12 inch sub. The Epic Conquest looks great because it's flat to about 16 Hz. The Elemental Designs dual 18 inch is another top shelf choice. The SVS Ultra also looks very sweet. There are many great subs discussed here - I want a flat, musical response down way, way low. There are great musical sounds way down there. To my ears, great lower harmonies add enhanced balance to an overall soundstage.

Musical clarity and balance is my first priority goal. A full HT experience should fall right into place and sound fabulous. I want to set up a live sounding, high-end soundstage that can take command of any situation first, then "forget the system" and really enjoy the sounds.

I'll post my results after working on placement and crossover points, if I don't end up in musical bliss for months like a absent minded professor. Please add comments in any way. This is my first post and YOUR posts have helped in countless ways over and over.

Thanks much.

I have 2 MBM-12's and a 3.3 Turbo. I tried different combos in my room (6000+ cubic feet with 2 large openings on the left to other parts of the house) and came up with the best way for me. I read a report written by mojave on SUB LOCALIZATION, http://forum.hsuresearch.com/showthr...ght=crossover? So I set up my 2 MBM-12's (one with each main 50hz up, E-90's) with a xover of 150hz, and a 3.3 Turbo (nearfield, 50hz down) behind the seating area. The MBM-12's sure take the strain off the mains and allow a higher xover and there is no localization of the Turbo. The bass punch is there and the SQ for HT & Music is excellent.

Bill

Just making sure I'm reading this right. You have your MBMs towards the front of the room (farfield) and the 3.3 behind you (nearfield)? MBMs crossed at 150hz?
I just finished some tweaks and have my MBM/2.3 combo set up in a opposite way of yours. Might have to try it the other way...

Correct! The MBM-12's are right next to the mains and blend quite well and xover'd at 150hz. 3.3 Turbo right behind the couch where I sit and xover'd at 50hz. The 3.3 Turbo acts like butt shakers when the bass is intense and I do have 2 butt shakers in the couch but never use them since the new sub setup. Movies and music are most excellent!

Bill

Looks like I have some more shifting to do...

What is the LFE on your avr crossed at? and mains?

Anyone ever attempted to use these with Planars? Magnepans specifically?

Planning a basement system & it would be nice to take some of the load off of the Maggies.....approx 15,000cu ft.....this is why I'm going with a Conquest

I just recently bought the Hsu VTF-3 MK3, which I love. But I still find myself looking at the MBM-12 almost everyday. So I believe that I will eventually be adding it to my setup.

Avr (Pio '94)LFE xover'd at 150hz, and the mains have no xover to adjust (JBL E90's). Here is a list of my gear:

Pioneer - VSX-94THX
Bue Jeans cables
JBL - E90 mains w/M2200 200 watt Mono Blocks
JBL - EC35 center w/M2200 200 watt Mono Block
INFINITY - Beta ES250 surrounds
JBL - E50 rear surrounds
HSU - (1) VTF-3 MK3 Turbo
HSU - (2) MBM-12 (one w/ea main)
Toshibia HD DVD AX2 (HDDVD)
Panasonic DMP-BD30 (BluRay)
Sony SCD-CE595 SACD (5 disc cd/sacd player)

Bill

My MBM's haven't arrived yet, but I wanted to answer a question at the beginning of the post. Why did I order the MBM's? I want elegant, full sound stage reproduction at ALL volume levels - low, medium and high.

80-85 dB on a C-weighted slow scale is very close to my max listening volume. Occassionally, I listen to higher volumes with great care. My bilateral audiogram test results look completely normal. I'm also very careful with headphones.

I was listening to CSNY's Judy Blue Eyes. I tuned my subs internal crossover way up to 120 Hz and adjusted the gain down slightly. Beauty unfolded. The "new" notes added between 50 to 120 Hz from the powered sub driver made such a enjoyable difference to my ears, that I had to locate a special unit(s) designed to fill this new mid-bass musical experience.

My modest 12 inch downfiring sub, adjusted to 120 Hz and placed up on a 18 inch table next to a RF-7's rear ports, blended "mid-bass" notes together. My whole system sounds "new".

Some recordings sounded muddy. Another member posted that final mixes vary greatly between recordings. Sub placement was very important. The sub has it's own dedicated hallway. With the hallways' far door shut, the overall blend between the sub and RF-7's sounded better than ever. Somehow, the closed hallway door pressurized and mixed the sub's output much better throughout the 30 x 30 sound stage.

I listened to many recording techniques/final mixes and made adjustments on my sub's crossover and position. The experience with my system made it clear that it needed a special unit(s) designed just to reproduce mid-bass music more accurately. I feel dedicated mid-bass units offer so much that they may become very popular.

The MBM's additional cost on top of a sub and mains is a real issue. New, top shelf high-end products are costly. One MBM behind the couch would have probably been perfect for HT. For music, I chose a stereo pair for headroom and to separate the musicians and instuments better playing at and reproduced at low, medium and higher volume levels.

Dan

We are all finding a benefit to having the MBM-12 whether it is for HT or just listening to our favorite music. I know for me that my setup has opened up a whole new world for me for music listening and has added more enjoyment to movies.

Bill

Ppl still buying this? Anymore +/- reviews?

I have a VTF-3.3 with Turbo placed on the right front corner of my room firing into the wall.

I have an MBM-12 nearfield behind my couch.

I have an Onkyo 705

I have 6 bookshelf speakers

What XO do you suggest that I use for my speakers and subs?
All suggestions are welcome.

Thanks.

Try 80hz across the front, 100hz for surround, and anywhere from 100-150hz on the LFE. MBM at 150hz out, 3.3 at 50hz in.

I followed your advice.

I set it to 80Hz across the front, 100hz for surround, and 120Hz on the LFE (The Onkyo 705 can only go up to 120Hz on the LFE).
And MBM at 150hz out, 3.3 + Turbo at 50hz in.

What I noticed immediately is there was no more boominess, and NO MORE localization.
By going MBM at 150hz out does it mean that my LFE in the Onkyo has now been bypassed?

What did I just do, and why does it make such a difference?

You didn't bypass the Onkyo. By using "out" on the MBM you're letting the receiver set the XO point.

What were your settings before that localized the subs?

I have had mine for about 2 months. 3 3 T front left corner and MBM behind the couch. 3 3 T xo in set at 50hz, MBM xo out and Denon 2808 xo currently set at 120hz.

Still playing some but enjoy this configuration greatly.

I'm still running 150hz on the xover and wouldn't do it any other way. There is so much more detail in the bass and upper ranges.

Bill

It's because you have two MBMs.

I had the fronts and the front surrounds at 150Hz, the back surrounds at 120Hz, and the XO at 100Hz.

There was a lot of boominess, and I could tell where the MBM was and could localize it. Now with your setting, the sound is flat and no localization.

Blu, that is because in the nearfield, one should generally not cross the MBM-12 much higher than about 80-100Hz, or else the module will be easily localizeable.

In my opinion, generally the best place to reproduce mid-bass (50-80Hz region) is in the nearfield, right next to the primary listening position. I like using the module sideways centered directly behind the couch. Sometimes people are not able to place the module right next to their primary listening position, or have other constaints related to the room or the capabilities of their front speakers, and in those cases it makes sense to use a couple MBM's to flank the L/R front speakers.

I spent some time comparing MBM-12 (nearfield) + VTF-3 HO/t (farfield) combo vs a VTF-3 MK3 (nearfield) and VTF-2 MK3 (nearfield) in our demo room, and to me the MBM-12 sounds more musical, more "tight", with less "boom" in comparison to the -2 MK3 and -3 MK3 on their own (all using an 80Hz crossover to the main speakers). I really love using the MBM in the system, as I feel the bass lines are more well defined, sound is cleaner (lower distortion), and headroom is higher.