Adding HSU VTF-3 MK3 W/Turbo & MBM-12

[Johnny04096]

I am in need of some advise with adding a HSU VTF-3 MK3 W/Turbo & an MBM-12 to my surround system. My related components are listed below. My problem is that I am having problems integrating the VTF-3 & MBM-12 within my current system. This is my first experience with subs, so please be patient with me. I tried using the 990's auto set up, but in doing this the 990 set the fronts as large. Thus, leaving out the benefit of the MBM-12 as well as trimming the sub outs to -12. Therefore the MBM-12 and the VTF-3 are never really heard from. The NHT VT-2's go down to 20HZ. I have tried to set things manually using both of the 990's sub out's, setting the crossover at the 990 to 80HZ and the MBM-12 to out with 0 phase and the same settings for the VTF-3. The problem is that I can easily hear and locate the MBM-12 and it sounds muddy to me, not tight and clean. I have the volume setting on the first notch. I also sense that the MBM-12 and the VTF-3 are overlapping. The MBM-12 is placed 3' to the left of the seating position, and the VTF-3 to the far right corner. As far as placement goes this is my only option, but I feel that this should not be an issue as the VTF-3 is non directional and the MBM-12 seems to me to be very localized. I think that things can be worked out, but I wonder if the 990's bass management is interfering in a negative manner. Maybe I need an external bass management component. Any help and advice would be greatly appreciated.

Johnny

1. Outlaw 990
2. ADA PTM-6150 6 CH x 150 amp
3. Oppo 981 DVD player
4. Roksan Radius 5 TT W/Music Maker 3 cartridge
5. L Audio A28 tube phono pre-amp
6. Little Dot 2 ++ headphone Amp
7. Dish 622 DVR HD receiver
8. Sony KDL52" XBR3 LCD HDTV
9. X-Box 360
10. NHT VT-2 fronts
11. NHT VS-2A center & surrounds

[Pete_Hsu]

Hi Johnny,

Would it be possible for you to work up a quick sketch of your room and post it here?

Did you set the crossover on the VTF-3 Mk3 to 50Hz? Also, by setting the crossover in your processor to 80Hz, the MBM-12 will handle primarily from 50-80Hz, and will roll off naturally below that. Just a couple more questions: is there anything placed close to the MBM-12 that buzzes and rattles during movie/music playback? Is the port unobstructed and firing forward, with the downward firing driver having good clearance between the woofer cone and the ground below?

Sincerely,

[Johnny04096]

Hello Peter,

Thank you for the response. I will try and get a sketch worked up. With the VTF-3 MK3 set to out, would it matter what it's crossover is set at? I also have the MBM-12 set to out as the processor is doing the crossover work with at a setting of 80Hz? There is nothing close to the MBM-12 that is rattling or humming. The port is facing towards the rooms center, and is unobstructed. The MBM-12 is sitting on a piece of carpet remnant as we have hardwood floors. The clearance for the cone would be the difference between the MBM-12's bottom footing/spikes and the woofer. Does the MBM-12 need to be a certain distance off the floor? Another question that I have is why would I not want to set the processor to cross over at 150 Hz? I have it in my head that the MBM-12 goes up to 150Hz, and it seems to me that this would be where I would want to cross the fronts over. What is the benefit of having the MBM-12 doing just from 80Hz to 50Hz? Most L/R mains can go down to 50Hz. Is it that I probably should not be using the MBM-12 with my L/R fronts?

Johnny

[Pete_Hsu]

Johnny,

Presumably your receiver/amp has a subwoofer/LFE output. You should set the crossover frequency on the VTF-3 Mk3 to 50Hz, and set the crossover to "in", while using a Y-adapter to split the signal from the sub out on the receiver to feed the MBM-12 and VTF-3 Mk3. Then in your receiver, set the distance for the subwoofer equal to the distance between the MBM-12 and the primary listening position. Feel free to take a good look at the pdf manual here: http://www.hsuresearch.com/products/mbm-12.pdf

Sincerely,

[Johnny04096]

Peter,

I have dual sub outs on the Outlaw 990. Dr, HSU, on the phone told me to run one cable to the MBM-12, and an other to the VTF-3. In other words one from each of the 990's sub outs. Set the crossover on the Outlaw 990 to 80 Hz and both the MBM & the VTF-3 to out. Your sugestion seems to be contradicting this recomendation.

Johnny

[Pete_Hsu]

Johnny, Dr. Hsu's advice should be good since you have two sub outs. Feel free to email techsupport over the weekend if you'd like to get some more feedback or clarification from Dr. Hsu. Thanks!

[RHui_BC]

any updates on this thread? how did the integration work out for you?
what are your impressions?

I just ordered mine too... hopefully things will go smoothly for me.

[Johnny04096]

any updates on this thread? how did the integration work out for you?
what are your impressions?

I just ordered mine too... hopefully things will go smoothly for me.

Hello RHui BC,

Unfortunately I emailed HSU tech support many weeks ago; with no response to date. I feel that my post were not really read thoroughly by Mr., Marchs, as is obvious by his reply's. So, to respond to your inquiry; if I was to re-evaluate my purchase of the MBM -12? " no way would I do it again", period. The MBM-12 unfortunately requires very exact positioning in order to blend within the system. And, even then, it is adding coloration to music reproduction. I have removed the MBM-12 from my system, and have since, achieved good results with the HSU VTF-3 Mk3 for movie replay, but not for music replay. I feel that the turbo adds a undesirable sonic attribute to the bass replay, and It does not re-produce a very accurate bass rendition, but instead a very colored, and exaggerated replay of the original bass. My feelings of course are subjective, I enjoy, and listen to music more then I view video replay. I am an accomplished musician, and feel very strongly that music reproduction should always be as close to the original production as is obtainable. My personal, and honest opinion is that the MBM-12 does not fit the required criteria for accurate music reproduction. The VTF-3 MK3 Turbo is good for movies only; period. These are my personal opinions of course and subjective thoughts, nothing more. Please use your own judgment in any purchase decision.

Thank You,

John

[Pete_Hsu]

Something must be amiss if you feel that turbo adds coloration to the bass. All the turbocharger is doing is lowering the port tuning. Do you notice any difference in bass quality when using turbo vs. plugging one port (in both cases, using extended bass mode set on VTF-3 amplifier)? It is important to make sure that the seal on the turbocharger is properly in place, that the pad is placed in between the turbo and base enclosure, and that no air is leaking from the port connection.

You shouldn't set your processor to crossover at 150Hz. With the MBM-12 in the nearfield position, it is best not to set the crossover higher than about 80 or 90Hz, because the bass will become very directional. If you could place the MBM-12 in between the main front speakers, then it would be fine to crossover at 150Hz, but not in the nearfield position. Also, the crossover on the VTF-3 Mk3 should be set to 50Hz, so that it handles 50Hz and below.

If you provide a sketch of your room, with room layout and dimensions, then we can assist further. Thanks