***Official HSU owners/support thread!*** - Page 7

The SMS-1 from Velodyne is very convenient. you hook up the mic and the unit to the TV, it takes measurements for you, and you adjust it on-screen. It also costs about $700 last I checked.

I personally use a Behringer Feedback Destroyer, or BFD for short. It is only about $100. But it is entirely manual, so you have to take your own measurements and put in the filter settings yourself. You can measure with Avia sweeps, individual test tones, or the freeware program Room EQ Wizard. REW is a great program, and you can take instant sweeps like those in the SMS-1. A BFD and REW is much, much cheaper, but takes some technical prowess on the user's part to be able to get good results with it. This is what I use, and the charts I posted were taken with REW.

Is that sub EQ'd? I was going to EQ my sub ( VTF3 MK2) but after moving it and installing bass traps, I decided not to EQ it. Attached is my graph.

Jim

First graph is pre-eq, second one is after eq.


That's a nice-looking graph! How much smoothing do you have applied to it? Do you have a graph of how it looks w/o the bass traps?

Thanks for the kind words.

I have not applied any smoothing to the graph and attached a graph that I believe was done prior to installing my traps (all 14 of them). The graph that I am posting is from TrueRTA, so it is not to the same scale (sorry).

I have a quick question on "room shakiness." Is this directly correlated to db? I was hoping that upgrading to a VTF3.3 with turbo would shake my place up more at the same volume levels. I've spent all weekend playing with it and am a little dissapointed. I've placed it in different spots, calibrated SPL levels to the other speakers, played with LFE and small/large settings, etc. It doesn't seem to shake my place up any more than if I disconnect it and just use the 350 watt 8" woofers in my mains (Rocket RS1000's). It does seem a little fuller and boomy though. I've also learned that my ears are even more sensitive than I originally though. About 95 db peaks in bass is all I can take in movies without my ears hurting from the pressure. My question is, when people talk about their whole rooms shaking, is this i only from playing at 115 db type levels? Is there a better sub for me, i.e. shakes the place more at a lower db? Maybe a downfiring sub? What about two smaller ones instead of a big one? I want impact without breaking my ear drums.

Are you running the subwoofer "hot" at all?

You need to watch at about -15 to -10 below your reference level to get pretty good shakes, unless you are running your sub really hot. If you listen at lower volumes, you need to run your sub hotter to get the room shaking. If you can't take the higher levels of bass (unless it's the other frequencies that accompany the bass), you're not going to get your room to shake.

Your solution may be bass shakers, devices that vibrate your couch or seats when bass hits to give the tactile sensation without the loud sound.

Does "hot" mean that the sub is calibrated a few db higher than the rest of the speakers? I have my speakers and sub at 75 db. I tried running the sub about 3 db higher but it seemed too boomy to me. Maybe my ears are just super sensitive to bass sounds? I know they are sensitive to highs, I've auditioned bright speakers and have had my ears ringing after. That's one reason I went with Rockets, they are known to be non-fatiguing and able to be played louder than others without hurting (which I've found to be true). Maybe my ears are just too sensitive in general for ground shaking home theater? Although I would think 100+ db would make a lot of people uncomfortable.

Yes, hot means calibrated to a higher level than the speakers.

Have you measured your sub's response, like by monitoring the SPL (on "FAST") while running a sweep tone like the ones found on Avia?

You may have "boomy" response, where certain frequencies are boosted by the room to be much louder. Bass sounds boomy, or like every single bass hit or bass note is in the same frequency range.

If that is the case, you can add bass traps and an eq to flatten the response so that all of the bass notes are at the same volume relative to how loud they should be. No more boominess, and you have strong, impactful bass at all volumes. If it's boomy, it can seem too loud, even cause headaches, even at lower volumes. Bass traps help by getting rid of the ringing and boominess in the room, so you hear more of the subwoofer itself rather than notes bouncing around and ringing in the room.


The red line in this graph shows my VTF-3.2, no bass traps or eq (ignore the other lines):


Here is after adding some bass traps and eq'ing the response:



Now all my bass notes and bass hits are forceful and as loud as they are supposed to be, leaving in the room gain at the low end below the range of frequencies that most bass in music doesn't touch. So it's still there to shake the room when called for in movies (the lower the frequency, the louder it needs to be to be heard and considered the "same" volume - 70dB at 60Hz sounds/seems much louder than 70dB at 20Hz).

I run the sub about even with the speakers for music sources, and 2~3dB hot for movies. I usually watch movies around -10 from reference level.


You can take any sub and throw it in a room and get plenty of boom. But it takes some effort to really let the subwoofer perform at its potential - in the way of bass traps and/or eqing. I'd personally rather have a $600 sub with my $100 eq and my bass traps (and more of them) than a $1000 sub and nothing else - because it will sound much, much better.

Hmm, I was hoping to avoid having to spend $1-2K on bass traps. What about my question on if db was directly correlated to shaking the room? If I'm never going to go above 95-100 db, should I get a cheaper subwoofer (or even just use the ones in my mains)? Do you think two smaller subwoofers will help shake the room better without being as boomy? Or will it just need more EQ?

I'd ask Dr Hsu these questions, too. I asked him for suggestions on crossover setting (given my Paradigm ref. front speakers and Pioneer receiver). Also asked him about my (and your) concern about the sub volume barely being on, and this is what he said:
"Its normal that the volume on the sub is up only half a tick from minimum. We have a lot of gain in the sub."

I have read this post and your post on AV123. I think your best bet is to put the sub as close to your listening position as possible. By doing this you will not have to have very high DB to feel the bass. As another suggested, call Dr. Hsu and see what he thinks.

Got my VTF-2 MK3 today and got it hooked up tonight. A few first impressions:



This sub is out of control, I have never experienced anything quite like this, my home theater is upstairs and this sub literally shakes the whole room. This is not an exageration at all, when the sub really hits it puts a shockwave through the floor beneath my feet that was a little scary at first.


When I really cranked it up my whole body would shake and the theater seating would rattle on the floor from the massive vibrations the sub produced.

So now after about an hour and a half of listening my ears feel like they are stuffed full of cotton.

Actually it is so powerful I'm not even sure I like it. For daily use I'm going to have to turn it way, way down.

A few questions:

1) Can this thing damage my house? Seriously the sub is just a monster, it is literally making the walls shake and is putting waves through the floor. (again it is upstairs)- this is no exaggeration. I've never experienced anything like it, and can only imagine that this is what an earthquake would be like.

2) Even if I keep it low can it still damage hearing? Right now my ears almost hurt, actually not that pleasant a feeling. How much quieter should I set the sub to be safe?

Also the sub was deceptively quiet. It seemed I couldn't always hear it so much as feel it. It seems very easy to play it too loud.

Any comments, thoughts, experiences, answers?

I spent about $250 on bass traps - GIK Acoustics. I have 4 of the 244 panels, but two of the monster traps or two of the corner wedge tri-traps would do about the same. If you buy the material (Owens Corning 703 and some wood, plus fabric to cover), you can probably get double what I have for $100 or less - if you build the panels yourself.

If you want to shake the room, it takes more SPL at lower frequencies. Smaller subs don't usually go as deep, so that probably wouldn't help. And dual subs can be much harder to integrate in the room properly.

I think I'm in the same boat as you. After movies now my ears hurt and feel pressurized and I have a headache. I'm sure some of it is because my room is untreated, but I just don't think I'm cut out to be a "bass freak". I've realized bass is deceptive, it doesn't sound as loud as if a high note was played at the same db. It also seems like in movies, the bass spikes compared to the rest of the action (about 20-25 db in some cases). I think I read somewhere that 85+ db causes hearing damage. Anyway, I think I will be returning my VTF3.3 Turbo. Not that there is anything wrong with it, I think it's perfect for bass hungry listeners. But I don't think I would appreciate it enough, I would have it turned down too low.

Subsolar & apples

Have you guys tried to set it up properly with a SPL meter? It almost sounds like you are running it hot, maybe too hot.

Can someone tell me how far away from the wall do the ports need to be?

I agree. If your system is properly calibrated, then it's not just your sub that will sound too loud. It's the whole thing. The solution being to turn it down.

If you do have it properly calibrated, you might want to experiment with placement. I know that my "usual" subwoofer spot had huge boundary reinforcement of some of 30hz and under frequencies to the point that it did sound completely unnatural even at lower volumes. The solution was finding the right spot for the sub. I also used the Velodyne SMS-1 Sub Eq to help tame my peaks in the frequency response.

A well positioned and properly calibrated sub should sound just right and only cause your ears to hurt if you are turning up your volume past comfortable listening levels for you.

I recently got the Hsu 2.3 and after SPL level calibration I was suprised at how low a level it was being driven. The goal is to have the sub blend and dissapear into your mains. I have the gain knob on mine set at the nine o'clock position with around 0 db on my receiver. As with the previous poster, I have also found that I need EQ to remove peaks caused by my room that placement restrictions just couldn't deal with.

All that said during some .1 sections of movies the effects are really tremendous. It just isnt' this way all the time. :-)

The Hsu owners manual says 3 inches.

Subsolar & apples

Both of you need to invest in an spl meter like others have said. You will be surprized as to how hot you are running a sub unless you take this step. From most posts that I have read and from my own experience, the volume on the back of the sub rarely needs to be past 9 o'clock. You do not need any special disc to do this, though it would be a good investment, just use the pink noise that your receiver produces. You will enjoy you new sub much more once you have it calibrated to the rest of your speakers.

Thanks, I looked through it last night, but in my excitement to set up my new toys I must have missed it

I already posted earlier that I calibrated everything to 75 db (using a radio shack SPL). I tried placing it in different parts of the room too. I think either the room needs massive treatments and/or I am overly sensitive to bass. There's nothing wrong with the Hsu or anything.

No problem. I've been there!

VTF 2.3 in black are showing in stock! Grab'em while their hot.

I've run the sub tests with Avia and a RS digital SPL meter and finding it hard to calibrate a consistent level on my HSU. I've been trying to calibrate at 70dB but find the Avia sub tones vary wildly in level. near the end of the each sub tone the level will vary like 6 or 7 dB. Should I be running the meter on slow response?

Yes

i agree, the gunfight scene scares the hell out me. I can not imagine what the added mbm would add to that scene.

just to help ease your pain. If you think that's a monster, I ordered a 3.3 with turbo. I have a dedicated theater around 4700 cubic feet in my basement with sound proofing insulation. My wife was on the crapper, two floors aboe the basement and she cut the tail off prematurely, as the toilet lid sounded as if it were going to rattle off. It was awesome.

ROTFL!!!! That's awesome, too damn funny. lmao

These new subs by HSU are truly powerful beasts, gotta love em'.

It varies like that because you're using Fast, and because you probably have about 10~15dB or more difference between the lowest and highest dB in that range (I think about 40~80Hz or so).

Try running the LFE sweep with the meter set to Fast and see how much variation there is.