Differences in sound quality/performance between the LV12R and LVX12/FVX15

I was curious about the difference in sound between the LV12R and LVX12/FVX15 in their respective high damping modes. I know the latter have deeper extension and a lower Q value but how do they sound subjectively different with various kinds of music and movies?


Also, if along the road I decide to add a second sub, would I be best served with another LV12R or the LVX12? I would likely place them in opposite corners of my square 12' by 12' by 8' room.


Also, does the LV12R have much more upper extension with the LFE input? 300Hz vs. 200Hz? Because the frequency response on the website in graph format looks pretty similar from 100Hz to 300Hz.

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Originally Posted by PlasmaPZ80U

I was curious about the difference in sound between the LV12R and LVX12/FVX15 in their respective high damping modes. I know the latter have deeper extension and a lower Q value but how do they sound subjectively different with various kinds of music and movies?


Also, if along the road I decide to add a second sub, would I be best served with another LV12R or the LVX12? I would likely place them in opposite corners of my square 12' by 12' by 8' room.


Also, does the LV12R have much more upper extension with the LFE input? 300Hz vs. 200Hz? Because the frequency response on the website in graph format looks pretty similar from 100Hz to 300Hz.

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I haven't compared the two, so I can't help you there. But, if your room is in fact sealed, since the length and width are equal you might look into placing the subs at midpoints of opposing walls if at all possible. You will get better reduction in standing waves with those placements as opposed to opposite corners. You might be able to play with the phase on one to get it great, but with midpoints of opposing walls, you don't have to go to the trouble. If you do go with midpoint of opposing walls you would probably want to get some smaller sealed subs. The L22 is kind of slim to help out with tight floorspace. Or an L12 or F12. In that small of a sealed room any of those subs will probably be just fine in terms of having enough output.

If the room is not sealed, then is really doesn't matter as far as what I mentioned before. This is because with the room being open the interaction between the two subs in the room is much more complicated and it gets tough to predict where to place they for the best performance.

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Originally Posted by N Boros

I haven't compared the two, so I can't help you there. But, if your room is in fact sealed, since the length and width are equal you might look into placing the subs at midpoints of opposing walls if at all possible. You will get better reduction in standing waves with those placements as opposed to opposite corners. You might be able to play with the phase on one to get it great, but with midpoints of opposing walls, you don't have to go to the trouble. If you do go with midpoint of opposing walls you would probably want to get some smaller sealed subs. The L22 is kind of slim to help out with tight floorspace. Or an L12 or F12. In that small of a sealed room any of those subs will probably be just fine in terms of having enough output.

If the room is not sealed, then is really doesn't matter as far as what I mentioned before. This is because with the room being open the interaction between the two subs in the room is much more complicated and it gets tough to predict where to place they for the best performance.

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The room is closed off with a door except for a small closet space, but the door is flimsy and in no way forms an airtight seal. I don't think I get any room gain, but I have bad room modes so they might be masking any room gain on the low end.

What I know is that if I place my sub in the front right corner then EQ it to MLP, the back left corner and back wall basically get the inverse frequency response of the front right corner. That is why I wonder if opposite corners would balance things out. Also, opposite midwall placement is not possible.

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Originally Posted by PlasmaPZ80U

The room is closed off with a door except for a small closet space, but the door is flimsy and in no way forms an airtight seal. I don't think I get any room gain, but I have bad room modes so they might be masking any room gain on the low end.

What I know is that if I place my sub in the front right corner then EQ it to MLP, the back left corner and back wall basically get the inverse frequency response of the front right corner. That is why I wonder if opposite corners would balance things out. Also, opposite midwall placement is not possible.

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Yes you are right. According to Harmon's research on this in a sealed rectangular room space the subs in opposite corners will give you the seat to seat variation of about halfway between just one subwoofer and two at opposing midpoints of the front and back walls. The opposing midpoints is actually about as you can get in a sealed rectangular room, in terms of minimizing standing waves and seat to seat variation.

It's not the end of the world if you can only get opposing corners. You will still get good performance. Also, as far as the door is concerned, I would imagine that the closet is small enough that it doesn't add that much extra space to pressurize. If it is in fact flimsy enough you might want to change it anyways with the subs you are considering, since it might be distracting hearing the slight movement on it with a bass heavy scene. That might make you want to just replace it with a more solid door. This flimsy closet door might also throw off the predictability of placing your subs. It ever so slightly makes the room no longer a sealed rectangular room.

I think that any of the subs you are considering should be plenty, as far as probably getting you where the room is pressurized. Unless you want to be able to cleanly hit the 115 dB peaks for reference volume, I don't think you need the bigger subs. That is if I'm understanding you correctly that the room is sealed and rectangular except a flimsy door on the closet.

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Originally Posted by PlasmaPZ80U

The room is closed off with a door except for a small closet space, but the door is flimsy and in no way forms an airtight seal. I don't think I get any room gain, but I have bad room modes so they might be masking any room gain on the low end.

What I know is that if I place my sub in the front right corner then EQ it to MLP, the back left corner and back wall basically get the inverse frequency response of the front right corner. That is why I wonder if opposite corners would balance things out. Also, opposite midwall placement is not possible.

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In a square room you certainly have room gain, but square rooms tend to have a lot more nulls because of equal interactions that cancel each other. Multiple subwoofers in a square room is always going to be better than one, because you can reinforce certain frequencies better with two woofers instead of letting the waves on the sidewalls continue to cancel each other out. I definitely think you'll get better response in your room with a second sub (identical!!!) in that corner.

I don't really get the bit about "inverse frequency response" that you mention. I think you mean that the phase will be 180 degrees in the other direction, leading to timing issues and slow bass? The best way to deal with this is with a corner bass trap to reduce that reflection and allow the other wave to stand out over it in amplitude, which will lower the amount of cancellation you're getting as well. I don't know if my physics lingo is correct, but hey :) Maybe Dave will chime in.

You want to keep the subs in phase to get the cancellation of the standing waves when you are placing them symmetrically across the room from one another. Just imagine the one frequency (and its harmonics) where the wave perfectly fits in the room. If you place a sub across the room from that symmetrically, then the wave coming out on the other side is inverted and the two cancel each other out. This is important in most rooms, where with just one sub, the frequency bounces back and forth and adds to the previous, creating huge peaks, or huge nulls depending on where you sit in the room. If the subs are 180 degrees out of phase and placed symmetrically across the room, I think that the standing waves would add together, making things worse. It is only predicable like this in a sealed rectangular room, which is why shooting for that is nice. Otherwise one is left playing with placement and the phase on one to get good seat to seat variation.

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Originally Posted by N Boros

You want to keep the subs in phase to get the cancellation of the standing waves when you are placing them symmetrically across the room from one another. Just imagine the one frequency (and its harmonics) where the wave perfectly fits in the room. If you place a sub across the room from that symmetrically, then the wave coming out on the other side is inverted and the two cancel each other out. This is important in most rooms, where with just one sub, the frequency bounces back and forth and adds to the previous, creating huge peaks, or huge nulls depending on where you sit in the room. If the subs are 180 degrees out of phase and placed symmetrically across the room, I think that the standing waves would add together, making things worse. It is only predicable like this in a sealed rectangular room, which is why shooting for that is nice. Otherwise one is left playing with placement and the phase on one to get good seat to seat variation.

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Indeed that is true. I just set mine both at 0 and let the receiver/processor do the phase adjustment through the distance measurement. Has worked well for me. In a normal 2 channel system without room correction/automatic measurement you have to be a lot more rigorous about it and do all of the dialing in yourself since there is no distance adjustment to account for phase, so yes, you're absolutely right for a 2 channel system.

What makes the 12 by 12 foot room such a challenge is that you get these standing waves building up in both directions at the same frequencies. The frequency that has a wavelength of about 12 feet is 95 Hz. This means that with one sub you will get massive peaks or nulls with a frequency close to 95 Hz, depending on where you sit in the room. The same will be true with multiples of 95 Hz. Anything that can be done in a square room to knock down these standing waves, like correctly placing 2 or 4 subs in the room and bass traps and corners traps, etc. will go a long way.

The nice thing about a square room is that the standing waves are very predictable. You don't get them happening at two different frequencies from front to back and left to right. As long as you address them in some way, you can still get good sound in a square room.

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Originally Posted by N Boros

What makes the 12 by 12 foot room such a challenge is that you get these standing waves building up in both directions at the same frequencies. The frequency that has a wavelength of about 12 feet is 95 Hz. This means that with one sub you will get massive peaks or nulls with a frequency close to 95 Hz, depending on where you sit in the room. The same will be true with multiples of 95 Hz. Anything that can be done in a square room to knock down these standing waves, like correctly placing 2 or 4 subs in the room and bass traps and corners traps, etc. will go a long way.

The nice thing about a square room is that the standing waves are very predictable. You don't get them happening at two different frequencies from front to back and left to right. As long as you address them in some way, you can still get good sound in a square room.

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Could not have said it better myself. 100% agree.

Just to clarify, the flimsy door is the one to the rest of the house, not the closet (which has 2 sliding doors that are pretty st