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Discussion Starter · #1 ·
Hi,

Often when people are comparing subwoofers, they compare what max SPL they are capable of producing at the lowest possible frequency. If one subwoofer has a higher SPL than another, it "wins" and is thus considered to be a better subwoofer than the other one.

But does that really tell the complete story? From my experience with subwoofers, I've also noticed other aspects that are important. For example:

* Some subwoofers sound similar regardless of frequency played. I.e. it is harder to differentiate between different notes/frequencies, which is not good.
* Some subwoofers have a "boomier" sound. Does this mean they are not as "fast" as others? Or have higher distortion?
* Some subwoofers have more "impact" than others.

So based on the above, can we conclude that "max SPL at lowest frequency" after all is not all that matters for subwoofers? And if so, is there something else that can be measured to capture other aspects, such as those mentioned in the bullets above? :confused:
 

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Data-bass.com has all the measurements that you can handle. Many graphs for you to dissect as well.
 

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A subwoofer that can play low loudly and cleanly will in most cases have no trouble doing the same for the rest of the LFE spectrum, thus qualifying it as a high quality subwoofer. "Fast" and "impact" are descriptions of what is heard, not what the sub is actually producing, and so are meaningless when used to quantify performance. Clean and loud are what you should ask of a subwoofer. The rest is up to you and your room.
 

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You want a subwoofer that can actually play far up the frequency spectrum as well. Some subs can play well beyond 120Hz, which is great because some subs setup in stereo at the front sound stage sound great up that high. And it give you crossover flexibility. Distortion is another factor - you want low of course. So all those things, including sensitivity and efficiency are also important.

So no, ultimate output at the lowest frequency is not the end-all-be-all measurement.
 

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Subwoofers are some what simple beasts. The primary metrics are SPL, extension and distortion. SPL is fairly significant in that in the majority of cases with two subs the one with a higher SPL capability will have lower distortion at a given SPL than the less capable one at the same SPL. Further, CEA 2010 burst numbers limit distortion so you do get a decent idea how loud they play clean "enough" for human brains. We aren't as sensitive to low frequency distortion as we are with higher frequencies.

Decay, impulse response and group delay are also players BUT they are not as critical as with say the midrange frequencies.


So yes there are other factors at play beyond SPL, extension and distortion but in all but the worst designed systems or alignments they are far behind in importance. The other 800 pound gorilla is the room and when you add that into the mix the secondary concerns regarding the subwoofer itself get pushed even farther down in importance.
 

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Subwoofers are some what simple beasts. The primary metrics are SPL, extension and distortion..
+1. The most difficult hurdle for a sub to clear is to go low and loud. If it does that then it's a very safe bet that it will do everything else required of it, as in comparison to going low and loud everything else is easy.
 

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+1. The most difficult hurdle for a sub to clear is to go low and loud. If it does that then it's a very safe bet that it will do everything else required of it, as in comparison to going low and loud everything else is easy.
I seem to recall that the late Tom Nuisane, when S&V actually published meaningful measurements, added to those measurements already mentioned one more….Bandwidth Uniformity……how flat the response was across the sub's useable range.
 

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I have to say, besides the room, the speaker cabinet is a major source of distortion if it isn't done properly. For music above the bass region, this is one reason why $10,000 and $30,000 speakers exist. The cabinet is a huge factor. For subs, it can be as well, as I've heard many commercial sub boxes rattle and resonate.
 

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Discussion Starter · #9 ·
+1. The most difficult hurdle for a sub to clear is to go low and loud. If it does that then it's a very safe bet that it will do everything else required of it, as in comparison to going low and loud everything else is easy.
Well, then what measurements capture these aspects?:

* Some subwoofers sound similar regardless of frequency played. I.e. it is harder to differentiate between different notes/frequencies, which is not good.
* Some subwoofers have a "boomier" sound. Does this mean they are not as "fast" as others? Or have higher distortion?
* Some subwoofers have more "impact" than others

Max SPL at lowest possible frequency does not. So then what measurements to look for?
 

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Well, then what measurements capture these aspects?:

* Some subwoofers sound similar regardless of frequency played. I.e. it is harder to differentiate between different notes/frequencies, which is not good.
* Some subwoofers have a "boomier" sound. Does this mean they are not as "fast" as others? Or have higher distortion?
* Some subwoofers have more "impact" than others

Max SPL at lowest possible frequency does not. So then what measurements to look for?
90% of what you are describing is due to the room, reference chapter 13 of Dr. Toole's book "Sound Reproduction Loudspeakers and Rooms". Impact may be a result of higher output in the "slam" range from one sub to another and midbass efficiency is sometimes compromised in the search for extension.
 

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Discussion Starter · #11 · (Edited)
90% of what you are describing is due to the room, reference chapter 13 of Dr. Toole's book "Sound Reproduction Loudspeakers and Rooms". Impact may be a result of higher output in the "slam" range from one sub to another and midbass efficiency is sometimes compromised in the search for extension.
Different subwoofers perform differently on the aspects I mentioned above, while playing in the same room and using the same equipment. So the subwoofer itself must affect those aspects too.

Having said that, of course room properties can affect the sound of the subwoofer. But the subwoofer itself also contributes to the sound and the aspects mentioned above.
 

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Different subwoofers perform differently on the aspects I mentioned above, while playing in the same room and using the same equipment. So the subwoofer itself must affect those aspects too.
You are somewhat correct. Often the more capable sub sounds worse...

Often a more capable (extension/SPL) subwoofer has the ability to bring out room issues that a less capable sub does not have. The key is that 90% of the issues you are asking about depend on the room/sub interaction and not the sub itself. Those are issues to be dealt with using placement, EQ and treatment. Almost always switching subs in and out to prevent these issues just finds a sub that plays nice with your room, more often due to deficiencies in the FR or SPL/Extension that causes a weaker or less "flat" sub to not excite room issues. These notions are what give rise to the myth that smaller drivers in a sub are "tighter" and "faster".

Do enough in room testing of different subwoofers and you will quickly see the correlation I have made. The louder and deeper a sub can go will almost always allow more room issues to rear their ugly head.

This is why even with the most capable subs multiple subs are still needed to get the best FR across the seating area.
 

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I don't think max SPL is all that matters, but apart from measurements and graphs, it's incredibly difficult to discuss bass quality objectively. Sound is subjective and personal, and beyond that, not everyone is on the same page in their use of descriptors. Some people misuse the term punchy bass, some people think 30 Hz is super deep, and then there are terms like warm, dry, wet, smooth, boomy, tight, effortless, controlled, and so on, all of which might fluctuate in meaning and perception from person to person. And furthermore, like has been said, everyone's rooms are different dimensions.

With that said, I love switching out and trying different gear, and I've had 12 different high-end sub setups in my car in the last few years thanks to having a friend who owns his own car audio shop. You can definitely hear varying sonic characteristics between them, and it's addicting. Even switching out only the drivers to other comparable drivers with matching power and enclosure requirements, and keeping the box and all settings the same, you can distinguish various aspects of their bass reproduction. Once each sub setup is tuned to the same house-curve, it's much harder to recognize differences, but you can still hear varying nuances in their SQ, mostly in how the voicing of their tonality sounds.

All of the subs I've had have sounded great, but for whatever reason, a few of them have especially clicked with me and sounded like ice cream for my ears. To me, those sonic and emotional differences are what matter most, and that is why I can't wait to try out the next sub. But that doesn't mean that those few subs will be sonic ice cream for someone else, because I've listened to the same sub, enclosure, amp, head unit, and DSP in two different sedans and had one sound vastly more impressive than the other. The room/car really does effect SQ.

Not having that same audio hookup in home audio makes me especially nervous in choosing a sub. Without the in-home trials that so many ID companies are offering, I'd probably be in decision limbo forever. The best home audio sub that I've had so far has been the SVS PB10-NSD, so I'm excited and anxious to see what some of the current $1000+ subs will sound like, and if all goes smoothly, I should be ordering a couple different ones this month.
 

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Hi,

Often when people are comparing subwoofers, they compare what max SPL they are capable of producing at the lowest possible frequency. If one subwoofer has a higher SPL than another, it "wins" and is thus considered to be a better subwoofer than the other one.

But does that really tell the complete story? From my experience with subwoofers, I've also noticed other aspects that are important. For example:

* Some subwoofers sound similar regardless of frequency played. I.e. it is harder to differentiate between different notes/frequencies, which is not good.
* Some subwoofers have a "boomier" sound. Does this mean they are not as "fast" as others? Or have higher distortion?
* Some subwoofers have more "impact" than others.

So based on the above, can we conclude that "max SPL at lowest frequency" after all is not all that matters for subwoofers? And if so, is there something else that can be measured to capture other aspects, such as those mentioned in the bullets above? :confused:
OP, I'm with you on this.

It does seem like SPL is the driving force when it comes to subwoofers but the guys here do look at the overall data. It's just really easy to explain SPL. The same way it seems like one car is better than another because of the 0-60 time or 1/4 mile time according to some guys.

I find that the best thing to do is to just do your our research and read the official XXX sub thread to see what owners are saying about the Sub.
 

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I have to say, besides the room, the speaker cabinet is a major source of distortion if it isn't done properly. For music above the bass region, this is one reason why $10,000 and $30,000 speakers exist. The cabinet is a huge factor. For subs, it can be as well, as I've heard many commercial sub boxes rattle and resonate.
Unless the cabinet is very poorly designed I suspect the driver itself dominates distortion. I am not sure I have ever measured a speaker so bad the cabinet was a "huge" factor (at least above the very cheapest lines). The room can emphasize frequencies but is an insignificant contributor to any sort of nonlinearity AFAIK, and the amplifiers (and rest of the electronics) are usually out of the picture below clipping.

That said, if the cabinet is not designed correctly for the driver, bad things can happen...
 

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I am not sure I have ever measured a speaker so bad the cabinet was a "huge" factor (at least above the very cheapest lines).
Yes, you're right, I should have have stated this differently. The cheapest speakers are the usually culprits, although there are few examples of some pretty high end and expensive speakers that have measured very poorly due to box coloration and/or a baffle that made the speakers sound pretty terrible (according to some reviews I've read).

It must be the case, then,that some of these very high end speaker designers using very heavy and expensive materials for the cabinets such as solid aluminum, stone/marble, etc. are doing so with diminishing returns.

I just know that I've put my hand on many speakers cabinets that vibrate considerably. Even some DIY sub boxes (sealed) that I've seen visibly vibrating under load.
 

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It must be the case, then,that some of these very high end speaker designers using very heavy and expensive materials for the cabinets such as solid aluminum, stone/marble, etc...
That's mainly done to convince customers that there's any reason to spend as much as they cost.

I just know that I've put my hand on many speakers cabinets that vibrate considerably. Even some DIY sub boxes (sealed) that I've seen visibly vibrating under load.
It's not what you make it out of that matters, it's how you make it. I don't use anything thicker than 1/2" plywood, and that includes pro-touring grade concert sound subs. None vibrate.
 
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