Sub Questions?

[KEW]

On the VTF-1 or 2, this review (of VTF-2) from AH is the only one I saw which has full data.
http://www.audioholics.com/subwoofer-reviews/hsu-vtf-2-mk5

It looks pretty nice. I still prefer the idea of buying a ported sub designed for music over a ported sub designed for LFE which can be adjusted to be a sealed sub for music, but if you are going to do it, Hsu is the man!

I'll also point out that none of the FR charts show the same reduction of bass you see in the 10S or the ULS15 in EQ2 mode.

Remind me what AVR you are using.

 

[speakerman39]

It does, since room-gain will likely add close to 10dB, but if you are concerned about the lack of control to tame it, my point is the 10S has the natural response which is equivalent to the ULS-15 tamed, but you avoid the price of the ULS15 because you are not paying for the additional capability plus the control to then counteract it (which makes the ULS15 cost twice as much on a per unit basis).

Kurt, I have a Denon X3000 that I got form Acc4less. It does not have Sub EQ HT. But, I can level match myself via my Radio Shack SPL meter. Placing subs equidistant from my MLP should keep things more simple. This go around I will be taking some measurements. That means that I will need to soon order me a CSL UMik 1 and download REW again. However, I am in no hurry to employ a miniDSP at this time. That will come later as I get more used to REW and learning my way around with it. Once done, then I will also order a miniDSP. At least, this is my plan for the time being.

Cheers,

Phil

 

[speakerman39]

On the VTF-1 or 2, this review (of VTF-2) from AH is the only one I saw which has full data.
http://www.audioholics.com/subwoofer-reviews/hsu-vtf-2-mk5

It looks pretty nice. I still prefer the idea of buying a ported sub designed for music over a ported sub designed for LFE which can be adjusted to be a sealed sub for music, but if you are going to do it, Hsu is the man!

I'll also point out that none of the FR charts show the same reduction of bass you see in the 10S or the ULS15 in EQ2 mode.

Remind me what AVR you are using.

Just out of curiosity have you looked at the curves of the Airmotiv S10 or even the S12? How would you compare them to the likes of the 10S's/ULS 15 MK2?

http://emotiva.com/resources/media/Frequency Response - Airmotiv S12.png

http://emotiva.com/resources/media/LF Boost Response - Airmotiv S12.png

SB1000

https://www.svsound.com/products/sb-1000

How about the SVS SB1000's? They look very much like the Speedwoofer 10S, no? Dual SB1000's look like a viable option as well, no? Or, even the Airmotiv S10/S12's, no? Trying to look more at the curves as in the past not so much. Seems to be a very useful tool. The Ryhtmik L12's are more like the SB2000's inmho, no?

Cheers,

Phil

 

[shadyJ]

It looks like what KEW is advising is a gradual low-end rolloff, probably something like a 12 dB/octave rolloff starting at 40 Hz to 50 Hz or so, so that the room doesn't overboost the deep bass. The problem is, no one really knows how their room will affect the low end, so looking at subwoofers before you examine the room's effect on the bass is like putting the cart before the horse. If I were you, I would get measurement equipment and maybe borrow a friend' sub and see how much room gain you get. Then, based on the data you gather, make your purchase decision. The Hsu subs do give you an element of safety since their low end is so adjustable. Also consider expanding your budget to include some SVS 16-Ultra subs, they have a ton of different room gain curves!

I wouldn't count on much deep bass from the SB1000 or L12, for the reason that they are stuffing a 12" driver with a not too amazing motor in a small sealed enclosure. Normally you want a driver with a powerful motor in a small box so that backspring pressure isn't a big deal. Otherwise the backspring pressure raises the resonant frequency and can cause a hefty amount of distortion in low frequencies. This is a recipe for a heapin' helpin' of even-order harmonics and other non-linear behaviors. I'm not sure how much the servo feedback system can mitigate this effect, but the SB1000 just uses what looks like a 24dB/octave filter and doesn't bother with low frequencies. The VTF subs also run into a filter in the sealed modes, but those filters can be set at either 25 Hz (the EQ2 mode) or 18 Hz (EQ1) in the VTF2. The VTF1's filters will be at somewhat higher frequencies.

 

[shadyJ]

On the VTF-1 or 2, this review (of VTF-2) from AH is the only one I saw which has full data.
http://www.audioholics.com/subwoofer-reviews/hsu-vtf-2-mk5

It looks pretty nice. I still prefer the idea of buying a ported sub designed for music over a ported sub designed for LFE which can be adjusted to be a sealed sub for music, but if you are going to do it, Hsu is the man!

I'll also point out that none of the FR charts show the same reduction of bass you see in the 10S or the ULS15 in EQ2 mode.

Remind me what AVR you are using.

I don't buy into the idea of speakers or subs that are meant for either music or movies. Speakers and subs should be blind to content- they should simply reproduce the signals they are given without distortion, regardless of the content of the signal.

 

[KEW]

Just out of curiosity have you looked at the curves of the Airmotiv S10 or even the S12? How would you compare them to the likes of the 10S's/ULS 15 MK2?

http://emotiva.com/resources/media/Frequency Response - Airmotiv S12.png

http://emotiva.com/resources/media/LF Boost Response - Airmotiv S12.png

The S10 is not bad. It starts a very gradual roll off at ~44Hz, is only 3.5dB down at 30Hz and 17dB down at 20Hz.

I don't like the look of the S12. It is essentially flat to 30Hz then only 8dB down at 20Hz.

For comparison, the RSL starts to roll-off at 40Hz, is down 4dB at 30Hz, and down 16dB at 20Hz.

SB1000

https://www.svsound.com/products/sb-1000

How about the SVS SB1000's? They look very much like the Speedwoofer 10S, no? Dual SB1000's look like a viable option as well, no?

No, the chart is not easy to read without vertical and horizontal lines going across it, but the SB1000 appears to have DSP applied to make it flat and the roll-off doesn't begin until around 27Hz and then it drops like a brick to -15dB at 20Hz! So that is not a very natural looking curve.

For comparison, the RSL starts to roll-off at 40Hz, is down 4dB at 30Hz, and down 16dB at 20Hz.

Or, even the Airmotiv S10/S12's, no? Trying to look more at the curves as in the past not so much. Seems to be a very useful tool. The Ryhtmik L12's are more like the SB2000's inmho, no?

Cheers,

Phil

The L12's "best" graph is the green "High" condition below, and while it starts to roll off at 40Hz, the servo extends the response such that it is only down ~1dB at 30Hz and down ~8dB at 20Hz

For comparison, the RSL starts to roll-off at 40Hz, is down 4dB at 30Hz, and down 16dB at 20Hz.

However, I am doing much more speculation about what curve would best fit your room after room gain that I am comfortable with.

One major reason I like the 10S is they are free to try with return shipping paid if they don't work. I think they are the best fit, but I don't feel comfortable saying to buy something you would have to pay to swap if they turn out not to work well!

 

[KEW]

I don't buy into the idea of speakers or subs that are meant for either music or movies. Speakers and subs should be blind to content- they should simply reproduce the signals they are given without distortion, regardless of the content of the signal.

So you don't believe LFE (which is expensive) is something desirable for HT and not useful for music?

I do understand what you are saying if you have the budget. However, with budgetary, and in Phil's case apartment restraints, why pay for what you will never use.
Also in the $400-$500 budget range, I have to believe a sub designed to maximize LFE is going to compromise SQ to get there.

 

[KEW]

Kurt, I have a Denon X3000 that I got form Acc4less. It does not have Sub EQ HT. But, I can level match myself via my Radio Shack SPL meter. Placing subs equidistant from my MLP should keep things more simple. This go around I will be taking some measurements. That means that I will need to soon order me a CSL UMik 1 and download REW again. However, I am in no hurry to employ a miniDSP at this time. That will come later as I get more used to REW and learning my way around with it. Once done, then I will also order a miniDSP. At least, this is my plan for the time being.

Cheers,

Phil

I think that is a very practical and workable approach to dual subs!

 

[KEW]

It looks like what KEW is advising is a gradual low-end rolloff, probably something like a 12 dB/octave rolloff starting at 40 Hz to 50 Hz or so, so that the room doesn't overboost the deep bass. The problem is, no one really knows how their room will affect the low end, so looking at subwoofers before you examine the room's effect on the bass is like putting the cart before the horse. If I were you, I would get measurement equipment and maybe borrow a friend' sub and see how much room gain you get. Then, based on the data you gather, make your purchase decision. The Hsu subs do give you an element of safety since their low end is so adjustable. Also consider expanding your budget to include some SVS 16-Ultra subs, they have a ton of different room gain curves!

I wouldn't count on much deep bass from the SB1000 or L12, for the reason that they are stuffing a 12" driver with a not too amazing motor in a small sealed enclosure. Normally you want a driver with a powerful motor in a small box so that backspring pressure isn't a big deal. Otherwise the backspring pressure raises the resonant frequency and can cause a hefty amount of distortion in low frequencies. This is a recipe for a heapin' helpin' of even-order harmonics and other non-linear behaviors. I'm not sure how much the servo feedback system can mitigate this effect, but the SB1000 just uses what looks like a 24dB/octave filter and doesn't bother with low frequencies. The VTF subs also run into a filter in the sealed modes, but those filters can be set at either 25 Hz (the EQ2 mode) or 18 Hz (EQ1) in the VTF2. The VTF1's filters will be at somewhat higher frequencies.

I totally agree with you!

I am saying buy subs you can return (and they will give him a reference) and you are saying borrow a sub and measure. Either way will get him there.

The only reference I have is knowing that he adjusted the PSA S1500 to the setting to compensate for the greatest amount of room gain using the room compensation adjustment.

The good thing is as long as he gets it within striking distance Audyssey can work it from there. OTOH, I'm not sure he really wants an in-room response of -0dB down to 20Hz in his apartment, so that could still be too much!

 

[shadyJ]

So you don't believe LFE (which is expensive) is something desirable for HT and not useful for music?

I do understand what you are saying if you have the budget. However, with budgetary, and in Phil's case apartment restraints, why pay for what you will never use.
Also in the $400-$500 budget range, I have to believe a sub designed to maximize LFE is going to compromise SQ to get there.

I have a large folder with FFTs from music recordings with lots of energy below 40 Hz, however, they tend to be electronic music and pipe organ music, so saying LFE, which I will take to mean content below 40 Hz, is only for movies is a bit if a generalization. If you mean traditional instruments, yes, that is mostly true, but still not entirely; consider that the fundamental of most keys of the lowest octave of a full piano dips below 40 Hz.

As for using budget considerations for foregoing low frequencies, usually the issue with very deep-digging subs have more to do with size rather than price. After all, Phil is willing to get VTF2s, which dig down to 18 Hz. The PB1000 can dig to 20 Hz and it is only $500, and the VTF1 digs to 25 Hz, and is only a bit more than $400. I don't see these subs compromising >40 Hz frequency performance to dig so low, but more size. The VTF2 has very good performance in this range; compare its sealed mode performance to the $1500 vaunted JL Audio E110; its keeps up very well, both in SPL and distortion levels. To further the point, compare the Rythmik LV12r with the L12: same power level amp and same driver, so there is not a big price difference but a big size difference, and this gives the LV12r a huge edge over L12 in low frequencies.

 

[KEW]

I have a large folder with FFTs from music recordings with lots of energy below 40 Hz, however, they tend to be electronic music and pipe organ music, so saying LFE, which I will take to mean content below 40 Hz, is only for movies is a bit if a generalization. If you mean traditional instruments, yes, that is mostly true, but still not entirely; consider that the fundamental of most keys of the lowest octave of a full piano dips below 40 Hz.

I would agree with your speculation on my position if you use 30Hz for the cut-off instead of 40Hz. -4dB at 30 Hz is about where the 10S I am recommending hits. if there is no room gain, Audyssey will handle that. However, I think it is reckless to take the approach that since we don't know how much room gain there is, we are best off assuming no room gain. I have seen room gain in every room I have ever put a sub in. Usually quite a bit as I am typically limited to positions along walls and more likely in corners! Perhaps if you can explain what situation might result in no room gain in a normal residential room, I can better accept what you are saying. I would love to see charts showing statistics on room gains!
I have little problem rolling off the 20-30Hz range for music, but realistically, after room gain and Audyssey, he will probably see good bass to the mid 20's. I'm not sure I would even want that in an apartment!

As for using budget considerations for foregoing low frequencies, usually the issue with very deep-digging subs have more to do with size rather than price. After all, Phil is willing to get VTF2s, which dig down to 18 Hz. The PB1000 can dig to 20 Hz and it is only $500, and the VTF1 digs to 25 Hz, and is only a bit more than $400. I don't see these subs compromising >40 Hz frequency performance to dig so low, but more size. The VTF2 has very good performance in this range; compare its sealed mode performance to the $1500 vaunted JL Audio E110; its keeps up very well, both in SPL and distortion levels.

Ouch! Bad example. I have a pair of E112's and they just suck for SQ, plain and simple. JL Audio gets an amazing amount of lows out of the small box, but I could never get good clean sound out of them! To my mind their best application involves heavy WAF constraint and wanting the best LFE possible out of a small box. Ideally your mains would allow you to cross them at 40Hz or lower and you could drop them for music!
I have to admit I am okay with some distortion when we are talking explosions. How would you know the difference?

To further the point, compare the Rythmik LV12r with the L12: same power level amp and same driver, so there is not a big price difference but a big size difference, and this gives the LV12r a huge edge over L12 in low frequencies.

But you should note that if you go to the Rythmik site, the following descriptions are provided for the two subs you mention:
http://www.rythmikaudio.com/products1.html

LV12R
Entry level paper cone subwoofer. Narrow 16” front baffle with rear port. Ideal for home theatre. 300WRMS.
Price: $569 shipped

L12
Entry level paper cone sealed subwoofer. Narrow 14” Ideal for Music/HT. 300WRMS.
Price: $539 shipped

So Rythmik is essentially saying that their LV12R is not an optimum sub for music as compared to the L12. Now I should follow that by recognizing that Mr. Ding is very picky about his sound for music and I know many have been delighted with the LV12R as a sub for playing music. Why would any manufacturer indicate that a particular (and in this case more expensive) product was not suited for an application which would reduce sales aside from having an impressive level of integrity?

 

[shadyJ]

The truth is, to the contrary of what many a audiophile might think, those explosions and that type of sound effects are far more complex signals and therefore more difficult to reproduce than pretty much any music (except for some experimental pieces). Music is relatively clean and simple to reproduce by comparison. The good news is, as you say, not many people care about the fidelity of explosion sounds and the like as opposed to music, because few people have a reference point for that content (how many people have heard what is sounds like when a helicopter smashes into the side of a building as our hero leaps to safety just in time?) However, if a subwoofer can accurately reproduce complex effects sounds, then accurately reproducing many music recordings is relatively easy.

I think Rythmik's marketing is banking on audiophile's prejudices against bass reflex designs, and I wouldn't take their claims that sealed is better for music very seriously. I would love to see a properly setup blind test of people trying to differentiate a ported sub against a sealed sub when the frequency response is the same. I think in laboratory level test conditions that a person with healthy hearing might be able to tell the difference with content that has port-generated frequencies and driver-generated frequencies simultaneously, because the port-generated sound is one cycle behind the driver, but only under exacting test conditions with the right content might that be possible. The thing is, most music does not even use port output very much, because that is the low end of a sub's response, so to say that sealed subwoofer X is better for music than ported sub Y is pure imagination, so long as the ported sub is properly tuned, and the port generated sound lay below typical music content, which is the case for all of these subs tuned in the 20 Hz range.

What's worse is that music which does use deep frequencies will be more distorted in a sealed design, if everything else is equal. The ports greatly alleviate the driver's need for excursion. The more excursion, the more distortion, especially as the voice coil nears the edge of the gap or as the suspension begins to tense up. I would much rather have a tad more group delay than a gob more harmonic distortion.

 

[shadyJ]

I have seen room gain in every room I have ever put a sub in. Usually quite a bit as I am typically limited to positions along walls and more likely in corners.

One thing I want to note about the above statement is, by placing the sub in corners and along walls, you are promoting boundary gain, and that will evenly affect all frequencies, not just deep frequencies. The 'room gain' we are talking about where the deep frequencies alone get a boost is called 'pressure vessel gain' and is a different acoustic phenomena.

I don't disagree that most conventional rooms will see gain of some magnitude, of both pressure vessel gain and boundary gain. I agree that Phil can expect to see a pretty significant gain.

Sometimes over-the-top deep bass can be fun though, and the VTF subs make it easy to switch between big deep bass and rolled-off deep bass. But the truth is that can be done with any ported sub: all you have to do is seal the ports.

 

[KEW]

I think Rythmik's marketing is banking on audiophile's prejudices against bass reflex designs

I do not see the sense in that! If Rythmik either said nothing or recommended any of their subs for both music and HT, a buyer who believes a sealed is better, will simply buy a sealed sub. How would indicating that their ported subs do not work well for music improve their sales?
OTOH, I can certainly see someone who need a a ported sub for their large room conclude that none of the Rythmik ported subs work well with music, so they then go to SVS, PSA, or Hsu who will happily sell them a ported sub for music.

 

[shadyJ]

Rythmik didn't say that their ported subs do badly with music. By saying that sealed is better for music, they are appealing to audiophiles who hold that notion. They don't want to turn off audiophiles who scoff at the very idea of a ported sub (yes, such fools exist). If they said that their ported subs are just as good for music as their sealed subs, audiophiles would take that as a red flag and go back to Rel and JL Audio. It is a sales tactic. Rythmik may also be advocating your reasoning that the gradual rolloff of sealed subs will sound better with rooms than the ported response, which is not a bad idea.

If Rythmik's sealed subwoofers actually are significantly better for music than their ported due to some kind of intrinsically qualitative aspect, then there is something wrong with their ported subs. However, I don't believe that to be the case.

 

[speakerman39]

Wow! This thread has really taken off. Have learned some things here. Just want to thank both Shady and Kurt for all of their input. Am getting much closer to my decision. Actually, there really is no hurry here. Want to make the absolute best decision for my needs. Have narrowed things down somewhat. Bit more research to do just yet. This has been a BIG help. Hope it is also helpful for others out there looking to get a new sub or two. Much appreciated guys!

Cheers,

Phil