VTF-3 MK4 sound/placement issues

[apoteker]

I just got my VTF-3 MK4 last month and I've been having trouble getting it to put out that "movie theater bass" sound that I was expecting. I have an Onkyo TX-NR 709 and I ran Audyssey after dialing in the HSU recommended setup parameters and then changed to the recommended 2 ports open, EQ2, 0.3 but the bass still sounds weak. Audyssey set the sub at +1.0 dB. The room that I have towork with is 14’8” x 14’ 3” with a tray ceiling that is 7’4” and has no windows. Any suggestions would be greatly appreciated.

[shadyJ]

Hmm, +1 is pretty loud, that might have something to do with nulls. You have to understand that movie theater bass is 95 dB with 115 dB peaks- at least that is THX Reference level- I wouldn't guess a single VTF3 would be able to do that at your listening position. I don't think just one VTF3 isn't going to give you Imax power in that room.

Another thing is, in my experience, Audyssey sets the bass at a kinda low point, it may very well be flat but it's no fun. What I would do is crank the sub volume in Audyssey and then run some demo scenes to see if the sub can do what you want. If the sub just giving you the feeling you want no matter how hard you push it, then it simply isn't able to pressurize that room as you would like. If it can give you the output you want, I would leave it at a higher setting than where Audyssey set it, HOWEVER, I would would not want it at a point where it is always being pushed hard. That will give you a more distorted sound, and it will shorten the life of the sub. Look at the woofer, if it is getting a real workout just to get to a level you are satisfied with, that is not what you want.

You could try different placements for it, that might help. Have you tried the sub crawling method of subwoofer placement? Place the sub at your listening position on your seat, then place your ears down at places in the room where the sub could go. Use the sub at the location that the sub sound loudest when its in your seat and you in a potential spot for it. If that doesn't do the trick, you will either want another sub of the same model or a more powerful sub. In my own home theater, I think my room may be only slightly larger than yours and I have four subs, each about as powerful as yours, and I get a terrific bass sound. I recommend the multi-sub route.

[Donkey545]

Have you set your speakers from large to small in the receiver?

[SME]

First check your crossover (speakers set to small with the crossover frequency set to whatever calibration gives you or 80 Hz, whichever is *larger*).

What about the sound is lacking? Is it not loud enough? Or do you not like the sound quality? It looks like your sub is next to a wall and fairly close to a corner. This placement should be good for loudness but may cause the bass to sound muddy compared to a movie theater and depending on your preferences.

If it's not loud enough, you may be sitting in a bass null. Try this: play a bass heavy scene you are familiar with and walk around the room. You will notice the sound getting louder as you move toward the walls. There will likely be narrow regions, roughly equidistant between each set of walls, where the sound gets a lot quieter. Where these regions meet in the center of the room, the sound will probably drop out even more. If you happen to be sitting in the null at the center of the room, then you will hear much less bass.

The solution to room nulls is to either sit somewhere else or move the sub as close to your seat as possible --- like, right behind where you sit. If you can face the woofer at your back (give at least 2" clearance in between the woofer and the sofa) you will also get more tactile bass (more feeling).

If you still want more bass output after addressing any room problems, then increase the sub output level in your receiver a few dB. As shadyJ said, a second sub can help if you like listening at high volume or want good sound for multiple listeners. I have a VTF-15H and VTF3-MK4 placed at each side of my sofa as end tables, with the VTF3 woofer firing toward the sofa, of course.

[apoteker]

I have the speakers all set to 80 Hz and Audyssey set the LFE to 120 Hz. The sound from the sub doesn't seem loud enough and I don't get that "chest thump" from the bass. I'll try the sub crawl/walk around to see if I notice a change in loudness. If I understand the suggestions and do increase the volume, I should do it from the receiver and not the sub, correct?

[Jacobariel]

Originally Posted by apoteker

I have the speakers all set to 80 Hz and Audyssey set the LFE to 120 Hz. The sound from the sub doesn't seem loud enough and I don't get that "chest thump" from the bass. I'll try the sub crawl/walk around to see if I notice a change in loudness. If I understand the suggestions and do increase the volume, I should do it from the receiver and not the sub, correct?

Start all over. First set the sub closer to a wall on a corner if you haven't already done it. Then set the sub volume knob closer to 9 o'clock. Then do Audyssey but only one position and go into the OSD and make sure the sub trim is somewhere between -3/+3 if it is then DO NOT touch the volume knob on the sub and redo Audyssey all over again this time all positions. Sometimes you have to work with it. I have the vtf3 mk4 and Dr Hsu gave me advise on room placement and on how to do the sub crawl using his cd. Maybe he will see this thread and give some input on your problem. You might want to call him. I did!

[Jacobariel]

I own the Hsu VTF3 MK4 but recently I won the Ken Kreisel 12012 sub. Will I be able to continue to use the Hsu with the Kreisel once it arrives since its different brand/specs?

[shadyJ]

Wow, how did you win a ken kriesel sub? Those are very expensive. As for using the VTF3 with one, that would be tricky to do well, but not impossible. They will perform differently, so what you don't want is for one of the subs to bottleneck the other's performance. I would guess the 12012 would have more output above the upper 20 hz range.

One thing you might try is using the VTF3 near-field, like as an endtable or right behind your seat, and using the 12012 corner loaded. To make this work easily it would help a lot to have a receiver that has Audyssey XT32 with the SubEQ (the Onkyo 818 has XT32 but not the SubEQ), because it takes care of frequency response, phase, and distance settings automatically. You could use the VTF3 like the way the MBM-12 is supposed to be used, and have the 12012 handle bass below a certain point and have the VTF3 handle bass above a certain point, but you would still want to use the VTF3 near-field for that application. If you can not accommodate the VTF3 near-field, I would use one sub or the other, but not both.

[Jacobariel]

Originally Posted by shadyJ

Wow, how did you win a ken kriesel sub? Those are very expensive. As for using the VTF3 with one, that would be tricky to do well, but not impossible. They will perform differently, so what you don't want is for one of the subs to bottleneck the other's performance. I would guess the 12012 would have more output above the upper 20 hz range.

One thing you might try is using the VTF3 near-field, like as an endtable or right behind your seat, and using the 12012 corner loaded. To make this work easily it would help a lot to have a receiver that has Audyssey XT32 with the SubEQ (the Onkyo 818 has XT32 but not the SubEQ), because it takes care of frequency response, phase, and distance settings automatically. You could use the VTF3 like the way the MBM-12 is supposed to be used, and have the 12012 handle bass below a certain point and have the VTF3 handle bass above a certain point, but you would still want to use the VTF3 near-field for that application. If you can not accommodate the VTF3 near-field, I would use one sub or the other, but not both.

My receiver only has Audyssey Multeq with one sub output. I was thinking of getting a Y adapter and placing the Kreisel on the left front corner and the Hsu on the right front corner both facing a wall or can I place the Hsu in the front but on in a corner say 5 feet from the Kreisel?

[apoteker]

Originally Posted by shadyJ

Hmm, +1 is pretty loud, that might have something to do with nulls. You have to understand that movie theater bass is 95 dB with 115 dB peaks- at least that is THX Reference level- I wouldn't guess a single VTF3 would be able to do that at your listening position. I don't think just one VTF3 isn't going to give you Imax power in that room.

Another thing is, in my experience, Audyssey sets the bass at a kinda low point, it may very well be flat but it's no fun. What I would do is crank the sub volume in Audyssey and then run some demo scenes to see if the sub can do what you want. If the sub just giving you the feeling you want no matter how hard you push it, then it simply isn't able to pressurize that room as you would like. If it can give you the output you want, I would leave it at a higher setting than where Audyssey set it, HOWEVER, I would would not want it at a point where it is always being pushed hard. That will give you a more distorted sound, and it will shorten the life of the sub. Look at the woofer, if it is getting a real workout just to get to a level you are satisfied with, that is not what you want.

You could try different placements for it, that might help. Have you tried the sub crawling method of subwoofer placement? Place the sub at your listening position on your seat, then place your ears down at places in the room where the sub could go. Use the sub at the location that the sub sound loudest when its in your seat and you in a potential spot for it. If that doesn't do the trick, you will either want another sub of the same model or a more powerful sub. In my own home theater, I think my room may be only slightly larger than yours and I have four subs, each about as powerful as yours, and I get a terrific bass sound. I recommend the multi-sub route.

OK, I was just able to get back to the theater today and I plan on doing the sub crawl tonight. Just a few questions first. Do I need to remove the sofa or just place the sub in the seat? I have already ran Audyssey so do I need to turn it off before doing the sub crawl or just rerun it after the crawl is complete? When I do place the sub, is it best to place the ports or the driver facing the wall or does it matter? Should I make all adjustments after the fact in terms of gain throught the receiver or on the sub itself? Sorry for so many questions but I thought that I would get them all out of the way at once. Thanks for any and all suggestions!

[shadyJ]

Originally Posted by Jacobariel

My receiver only has Audyssey Multeq with one sub output. I was thinking of getting a Y adapter and placing the Kreisel on the left front corner and the Hsu on the right front corner both facing a wall or can I place the Hsu in the front but on in a corner say 5 feet from the Kreisel?

The problem here is, one sub is likely to be so powerful that the other sub can not keep up with it. I think that the 12012 will be so powerful in mid bass that the VTF3 will be driven to distortion to add any meaningful output at all. I'm just guessing here, I don't think the 12012 will be tunes as low as the VTF3 so maybe the VTF3 can help a bit in the deep bass, below 30 hz, maybe. But this is all assuming that that KK12012 is a lot more powerful than the VTF3, I am not one hundred percent certain of that. Anyway, you own both subs, so you can do a comparison. If the 12012 is just so much more powerful than the VTF3, I would not try to integrate them into a single system, I would only use one or the other.

One thing I would mention is, while the 12012 is no doubt a powerful sub, I think there is a chance it could be not exactly the greatest sub you can get for $3k. I think there might be solutions out there with a lot more bang for the buck at $3k. A LOT more. For example, three VTF15h subs. If you haven't opened it yet, you might just consider selling it and use the money for something else, especially if you are happy or close to happy with your VTF3. If the VTF3 doesn't quite do it for you itself, you could still get one or two more VTF3s, have a waaay easier time integrating them, and have a nice chunk of money left over. I would rather have a multi VTF3 system than a single 12012 system personally.

[shadyJ]

Originally Posted by apoteker

OK, I was just able to get back to the theater today and I plan on doing the sub crawl tonight. Just a few questions first. Do I need to remove the sofa or just place the sub in the seat? I have already ran Audyssey so do I need to turn it off before doing the sub crawl or just rerun it after the crawl is complete? When I do place the sub, is it best to place the ports or the driver facing the wall or does it matter? Should I make all adjustments after the fact in terms of gain throught the receiver or on the sub itself? Sorry for so many questions but I thought that I would get them all out of the way at once. Thanks for any and all suggestions!

If you can place the VTF3 on the seat where the driver would be as close to your ears as possible, that would be ideal, but it is a large sub so that might be kind of awkward. You will want to turn audussey off before you do a sub crawl. It doesn't matter if the driver or the ports face the wall, you will want to give the ports a few inches of space if they are facing the wall though. To do the sub crawl, you just need to keep the sub at the same loudness level throughout the testing. After you have found the best place for the sub, set its volume knob at 9'o'clock, and the do all the other volume adjustments through your receiver.

Hopefully this helps, feel free to ask more questions if you have them. Let me know how it goes.

[apoteker]

Originally Posted by shadyJ

If you can place the VTF3 on the seat where the driver would be as close to your ears as possible, that would be ideal, but it is a large sub so that might be kind of awkward. You will want to turn audussey off before you do a sub crawl. It doesn't matter if the driver or the ports face the wall, you will want to give the ports a few inches of space if they are facing the wall though. To do the sub crawl, you just need to keep the sub at the same loudness level throughout the testing. After you have found the best place for the sub, set its volume knob at 9'o'clock, and the do all the other volume adjustments through your receiver.

Hopefully this helps, feel free to ask more questions if you have them. Let me know how it goes.

Thanks for your help. I followed your advice and the sub is going to be moved to the opposite diagonal corner of the room (instead of front left it will be rear right). It sounds 100% better and I haven't even reran Audyssey yet. The only thing that I can say about the new setup is that I think the bass is now localized and I can tell it is coming from the rear right. Would Audyssey correct that and how important is it to place the Audyssey microphone on a tripod? I don't have one but I'm willing to get one if it would make a noticeable difference. Thanks again for your suggestions, the difference is night and day.

[shadyJ]

Audyssey may or may not get rid of the localization. What is causing the localization is bass above 80 hz or so. Bass becomes non-directional below 80 hz, so you shouldn't be able to tell where sound is coming below that point. Audyssey will set your sub's crossover point in the receiver, and it will do so based on the capability of your mains. If your mains have decent bass, Audyssey will set them well below 80 hz. Anyway, regardless of where Audyssey sets the crossover point at, you can always go in and reset the crossover yourself to whatever point you want, so you will be able to make the sub less localizable if you wish.

As for a tripod, it isn't the tripod that is important, it is not having surfaces or hindrances near the microphone that is important. If you can suspend the microphone or mount it on something that isn't obtrusive to the incoming sound waves, that will do.

[apoteker]

I had to set the microphone on other surfaces before when I ran Audyssey so I'll see about getting an inexpensive tripod this time around. Originally it set the LFE to 120Hz so I'll see how it goes this time around. If it stays the same I might change it to 80Hz and see how that sounds. Thanks!

[shadyJ]

Your mains look pretty beefy, if Audyssey is setting them to 120 hz, something isn't going quite right over there. What speakers are those?

[apoteker]

Originally Posted by shadyJ

Your mains look pretty beefy, if Audyssey is setting them to 120 hz, something isn't going quite right over there. What speakers are those?

No, Audyssey set the LFE for the sub to 120Hz. It set the mains to 40Hz and I changed them to 80Hz. The main speakers are Polk RTi A7s and the center is a Polk CSi A6.

[shadyJ]

I see. I agree with you, I would set them both at 80 hz and see what happens.

[SME]

Hi apokeker,

I'm glad you found a better location for your sub. I strongly recommend turning Audyssey off when doing the sub crawl and leaving it off until you can recalibrate with the new location. Definitely use a tripod with the calibration mic because any mechanical vibrations that reach the microphone will be picked up as extra bass and will cause the sub output after calibration to be set unevenly and too low.

Sub localization has many potential causes. In my opinion, the conventional wisdom that subs can't be localized if crossovers are set at or below 80 Hz is not accurate. Even if the crossover is set at or below 80 Hz and the sub is not producing audible distortion above 80 Hz, other factors can contribute to the perception of localization: (1) more buzzing/rattling of objects in the room or of the room itself in certain regions; (2) uneven in-room response. The impact of (2) will be more pronounced when sitting at or near room nulls where the sound level and phase may vary considerably within a narrow region.

To identify buzzing and rattling in the room use the test tone sweeps on the included Hsu CD. Audyssey calibration can help with uneven room response but only to a point. If the sound still bothers you after calibration, you may want to consider other placement or seating options or start budgeting for a second sub.

[Jacobariel]

Originally Posted by shadyJ

The problem here is, one sub is likely to be so powerful that the other sub can not keep up with it. I think that the 12012 will be so powerful in mid bass that the VTF3 will be driven to distortion to add any meaningful output at all. I'm just guessing here, I don't think the 12012 will be tunes as low as the VTF3 so maybe the VTF3 can help a bit in the deep bass, below 30 hz, maybe. But this is all assuming that that KK12012 is a lot more powerful than the VTF3, I am not one hundred percent certain of that. Anyway, you own both subs, so you can do a comparison. If the 12012 is just so much more powerful than the VTF3, I would not try to integrate them into a single system, I would only use one or the other.

One thing I would mention is, while the 12012 is no doubt a powerful sub, I think there is a chance it could be not exactly the greatest sub you can get for $3k. I think there might be solutions out there with a lot more bang for the buck at $3k. A LOT more. For example, three VTF15h subs. If you haven't opened it yet, you might just consider selling it and use the money for something else, especially if you are happy or close to happy with your VTF3. If the VTF3 doesn't quite do it for you itself, you could still get one or two more VTF3s, have a waaay easier time integrating them, and have a nice chunk of money left over. I would rather have a multi VTF3 system than a single 12012 system personally.

Forgive my ignorance but if I try both subs at the same time how will I know if the Hsu is distorted?

[SME]

Jacobriel,

My guess is that the KK and Hsu subs will not integrate well because their designs are substantially different.

I suggest you listen to each sub on its own and decide which you like more. Then, move the other sub to another system or sell it.

[shadyJ]

Originally Posted by Jacobariel

Forgive my ignorance but if I try both subs at the same time how will I know if the Hsu is distorted?

If it is making any kind of mechanical noises. Also if it is producing frequencies above the one it is attempting to produce, this is called harmonic distortion, so if it sounds 'higher pitched' than your other subs while reproducing the same material, that is distortion.

[apoteker]

Originally Posted by SME

I'm glad you found a better location for your sub. I strongly recommend turning Audyssey off when doing the sub crawl and leaving it off until you can recalibrate with the new location. Definitely use a tripod with the calibration mic because any mechanical vibrations that reach the microphone will be picked up as extra bass and will cause the sub output after calibration to be set unevenly and too low.

Sub localization has many potential causes. In my opinion, the conventional wisdom that subs can't be localized if crossovers are set at or below 80 Hz is not accurate. Even if the crossover is set at or below 80 Hz and the sub is not producing audible distortion above 80 Hz, other factors can contribute to the perception of localization: (1) more buzzing/rattling of objects in the room or of the room itself in certain regions; (2) uneven in-room response. The impact of (2) will be more pronounced when sitting at or near room nulls where the sound level and phase may vary considerably within a narrow region.

To identify buzzing and rattling in the room use the test tone sweeps on the included Hsu CD. Audyssey calibration can help with uneven room response but only to a point. If the sound still bothers you after calibration, you may want to consider other placement or seating options or start budgeting for a second sub.

Thanks! I did turn Audyssey off before doing my sub crawl so I think I'm good there. I went out and bought an inexpensive tripod to use when I recalibrate with Audyssey so hopefully that will help. I've got a rattle in the overhead return vent but it's only up there with a pressure fit right now so hopefully it will go away when I tighten it down. The sub output is phenomenal right now, even sitting in what I'm sure should be a null spot (directly in the center of the room). I know that Audyssey recommends for the sub level to be set at 75db which translates to a little before 9:00 on the gain dial before starting calibration. Hsu recommends setting it at 9:00 exactly before running Audyssey (which would be louder than the 75db). Any opinions as to which way should I go or am I just splitting hairs at this point?

[SME]

The right gain setting for the sub will yield a sub level (in the receiver) close to "0 dB" after calibration. How close to "0 dB" depends on your receiver. I'd say +/- 5 dB is probably fine. Where it becomes an issue is if the calibrated level is outside the range that the receiver control can do. My receiver can't set the level above or below +/- 12 dB, so if the calibration yields either +12 dB or -12 dB, then I know I need to adjust the gain and redo it. The suggested "9:00" figure is a starting point and may be too high for you. My two Hsu subs are set about half way between "min" and 9:00.

[Jacobariel]

Originally Posted by shadyJ

Wow, how did you win a ken kriesel sub? Those are very expensive. As for using the VTF3 with one, that would be tricky to do well, but not impossible. They will perform differently, so what you don't want is for one of the subs to bottleneck the other's performance. I would guess the 12012 would have more output above the upper 20 hz range.

One thing you might try is using the VTF3 near-field, like as an endtable or right behind your seat, and using the 12012 corner loaded. To make this work easily it would help a lot to have a receiver that has Audyssey XT32 with the SubEQ (the Onkyo 818 has XT32 but not the SubEQ), because it takes care of frequency response, phase, and distance settings automatically. You could use the VTF3 like the way the MBM-12 is supposed to be used, and have the 12012 handle bass below a certain point and have the VTF3 handle bass above a certain point, but you would still want to use the VTF3 near-field for that application. If you can not accommodate the VTF3 near-field, I would use one sub or the other, but not both.

I am actually using both subs and they both sound nice together. I only noticed that the Hsu does not have the punch in certain areas of the room but with both subs from the MLP gave me an increase of +3 or so. DrHsu suggested I set the VTF-3 crossover to 50 and to IN so that way I can get higher output overall if I limit the VTF-3 to reproduce only 50 Hz and below. The combination of subs sounds smoother now but I lost spl at MLP.

[Radon]

His room is 14 x 14 x 7..ish is there an issue with a room that is evenly laid out like that giving dead sound?

[ATL]

Originally Posted by Radon

His room is 14 x 14 x 7..ish is there an issue with a room that is evenly laid out like that giving dead sound?

"The cubical room distributes modal frequencies in the worst possible way -- by piling up all three fundamentals, and each trio of multiples with maximum gap between. Having any two [room] dimensions in multiple relationship results in this type of problem. For example, a height of 8 feet and a width of 16 feet means that the second harmonic of 16 feet coincides with the fundamental of 8 feet."
--The Master Handbook of Acoustics [F. Alton Everest, TAB BOOKS 1989]

In a 14'x14' room, the first mode will be around 40 Hz, or the low E string on a bass. You'll get little or no room-boost below that point, but above there will be very strong peaks and valleys because of the basically square dimensions of the room.