Just how much better is 2 subwoofers? - Page 4

If a sub's "inherent capabilities" and "limiting nature" mean it will do better with HT content than with music it's defective. ... A sub that does go lower than the needs of music require should not work any less well with music content than one that doesn't go as low. If it does it's flawed.

Originally Posted by eljaycanuck 

It would seem, then, that my PB12-NSD was flawed.

If one just grabs and places "ANY" sub in a room blindly, then there's no standard in which to base any comments. No standards of consistency, then their can't be a rational conversation.

If it didn't have flat response from 40Hz to 100Hz then yes, it was. That's what's required of a music only sub. For good HT results it should be flat to 30Hz or lower.

Originally Posted by eljaycanuck 

To the best of my recollection, the FR curve was pretty flat to crossover (80Hz), although there was a bit of a peak at ~22Hz. I'll have to see if I can find a pic of that curve, for my own curiosity. Meanwhile, I'll step out of this thread. Apologies for the interruption.

Transient Response

Transient response refers to the ability of the subwoofer system to reproduce quick changes (transients) in the program material accurately. This is often interpreted as "tightness" or "looseness," which might be a dangerous terminology, since many people are more influenced by tonal characteristics when asked to qualify the "tightness" of the bass. Transient response is actually a function of accuracy in relation to time, rather than frequency. In music, sounds like drum strikes and quick bass guitar pulses are good tests of a subwoofer system's transient performance. A system with good transient response will reproduce these sounds with clear, "tight" definition. A system with poor transient response tends to blur these sounds over time, due to the speaker's inability to stop and start quickly enough to react to the signal accurately.

It is generally accepted that an optimized sealed enclosure exhibits the best transient response characteristics. The control provided by the air-spring in a good sealed system contributes to generally outstanding transient behavior (Please note that at very high power levels, the increased distortion can overshadow this advantage).

A ported enclosure can also achieve good transient behavior, but it will never be as good as an optimized sealed enclosure. It is possible, however, for a well-designed ported enclosure to have better transient response characteristics than sealed enclosures with higher Qtc's (above 1.0). The specific alignment of the sealed and ported enclosures plays a huge role in determining the transient characteristics of each individual subwoofer system.

Single-Reflex bandpass designs can also have good transient characteristics if their bandwidth is fairly narrow, but again, not as good as an optimized sealed enclosure. As the bandwidth becomes wider, their transient response can degrade considerably.

Dual-reflex designs generally exhibit inferior transient response characteristics when compared to the other designs. As with single-reflex designs, narrower bandwidths produce better transient performance than wider ones.

Originally Posted by BeeMan458 

An over driven driver is an over driven driver and it doesn't matter if the driver is being over driven by a music track or a movie based sound track. The demands on the driver are greater than the capacity of the driver. If one doesn't over drive the driver, there won't be this glaring, human caused problem. If one is consistently over driving the driver, they need more capacity and their choice in subwoofer is the limitation, not the choice of content.

Don't blame the driver for a person's bad decisions.

Originally Posted by BeeMan458 

If a subwoofer system is not dialed into the room's acoustics properly, the room's acoustics are going rob the subwoofer of performance and the user is going turn up the volume to compensate for the cancellation and in the process, ask more of the system then it's capable of providing. Again, the problem is a user caused problem. The content is not a consideration as to why the subwoofer system is not performing according to the desires of the owner.

If one wants it loud, then dey gonna have to hit the hip and break out the Benjamins. If dey don't wanna break out the Benjamins then the owner of the subwoofer system is just going have to lower their sonic expectations and keep the MCV turned down to a level the subwoofers can handle. Content has nothing to do with the final results of a poorly chosen and integrated subwoofer system.

-

If a subwoofer system is not dialed into the room's acoustics properly ...

Originally Posted by craig john 

A sub with poor transient response, (overhang/ringing), might have a flat FR, but still not sound great for music. OTOH, it might sound great for movies in that it would make those explosions sound even boomier.

Originally Posted by Thomas 1966 

I was replying to a response of more subs all together side by side is just for looks and not much else just trying to say I know the increase was not in my head as I have no meter.new subs just arrived as i am writting this have to paint my roof first but later today can hook up the new ones. cant wait! Yes of course it will be louder I am not complaining at all was just statting facts of how more is louder and I love it for music could be better for HT as no number of these subs will make for great HT. will move on to having just dayton 18 inch subs some year but for now it is just ok
At least I learned allot from this.

Originally Posted by eljaycanuck 

As far as the whole "there is no 80/20" thing goes, you keep putting the cart before the horse. If someone is considering purchasing a subwoofer and he is asking for a recommendation based on certain criteria (listening preferences, room size, budget, etc.), telling him he needs to dial the subwoofer into his room's acoustics is not useful information at that point in time because - wait for it - he doesn't have a subwoofer.

Your ability and/or willingness to measure your room's response should be a factor in your buying decision.

If you are not willing or able, you should just buy some cheap sub(s) and be done with it. No need to spend the money on quality subs because you will never get your money's worth out of them.

Originally Posted by eljaycanuck 

The recommendation still has to be made based on the buyer's list of criteria (budget,...

Originally Posted by wvu80 

Hi, this is my first post, so please allow me to jump in, as I am following the discussion and it speaks exactly to my needs.

---snip---

I have researched this sub info to death, upgraded my knowledge base, and I am still completely unsure. I know what I like in music and what I like to hear when listening to equipment, which are two different things. I like to think I have some knowledge, but I lack wisdom. I have another limitation; a wife who HATES things that make sound that take up space in the living room.

I was also looking at the Klipsch RW-12D for $300. Just when I think I have decided on a single 12" sub with 250 watt power supply, I change my mind and think I need a couple of smaller 10" subs such as the Dayton Audio Sub 1000 10" sub with 100 watt power amp at around $125 each with shipping.

My usual philosophy is that for the same price, one quality thing is better than two less quality things, but because of the nature of the beast, subs seem to be different. I read further upstream that two cheap subs might have benefits over a single sub, so I am officially still undecided. I could afford something in the $500 range, but I'd like to jump in slowly at around $300 or so and evaluate for myself.

Please feel free to guide and advise me. All opinions are welcomed, and even if we disagree, I don't take things personal, and I always post with a smile on my face.

Originally Posted by Louquid 

If a person isn't willing or able to measure the in room response, then they should just buy the best sub they can afford. Getting 85% of your money's worth from a $500 sub will still give you much better performance than getting 85% of a $100 sub.

Originally Posted by eljaycanuck 

The recommendation still has to be made based on the buyer's list of criteria (budget, listening preferences, room size, etc.). His willingness to measure his room's response doesn't alter his list of criteria, and it doesn't change the fact that he doesn't yet have a sub.

Originally Posted by BeeMan458 
IIRC ...

wvu80: I want the musical support of a sub 80%, with explosions in DVD's 20%, less important.

BeeMan: Just an understanding, there is no 80% music and 20% movie based sound track as there's only the accurate reproduction of frequencies ...

wvu80: Got it. I wasn't clear, but I meant my priorities are 80/20 biased towards having a good musical experience.

BeeMan: I do understand. Uninitiated folks don't realize, one can't anthropomorphize frequency (sound) reproduction into a fractional based listening standard. ... And then there's this whole room based acoustical thing (echos) that is a natural based evil doer (exists sans humanity) out to ruin everybody's listening pleasure. A gremlin if you will and more important than the subwoofer choice itself, is the need to tame a room's acoustics (correcting for conflicting sound wave interaction; modes) so the listening experience won't be attenuated (nulls) due to poorly integrating one's subwoofer choice into a room's acoustics.

Originally Posted by Alan P 

Ummm...not neccesarily. If you're stiing in a null and have limited placement options, it ain't gonna matter what sub you get.

I cite the many, many posts here from members who have bought "quality" subs and are disappointed (from slightly, to greatly) with their performance and can't figure out why.

Originally Posted by Louquid 


Lets say you have a $200 sub sitting in a certain corner of your room. You've put it here because this is where you found it performed the best via a sub-crawl.

Now, lets say that you notice you have a peak around 45Hz and a null around 32Hz with this sub. Sub only has usable output down to 30Hz in ideal conditions. You can basically say that your sub is only usable down to around 33Hz, and you hear a bit of bass around 30Hz or so.

Now, put a sub that has usable output down to 20Hz in that same location and you will most likely see the same null and peak as the previous sub.

Difference here, is that you'll have output down further now, and most likely have higher quality bass all around.

I'm not saying a more expensive sub will remove the issues your room creates.

I'm just saying that the higher quality sub should give you more performance than the lower quality sub if everything else remains constant.

Originally Posted by Bill Fitzmaurice 

You will see the same null and peak as that's sourced by the room dimensions, not the sub.
Lower, yes. Better, not necessarily.
Good, because it won't. The only fix for room modes is multiple subs.
Maybe. For the most part what you get with more $ is a sub that goes lower and/or louder, but that doesn't necessarily translate to more performance. It does if what you need is lower and louder, but if the issue is room modes and the current sub goes low enough then the best place to spend more money is on another sub, which will help to fix the room and give more output as well.

Originally Posted by Louquid 

This is what I was trying to get at. Louder and lower is what I was considering when I spoke of better performance.

Originally Posted by craig john 

You're misunderstanding the dual subwoofer outputs. Just because you have 2 subwoofer outputs doesn't mean you can do "stereo" subs, or even run different outputs to the two subwoofer pre-outs. Your manual says:
http://filedepot.onkyousa.com/Files/own_manuals/TX-NR717_English.pdf?CFID=2454328&CFTOKEN=37093083&jsessionid=f0305697ed33d92f7bc1695b57bb05211665
Page 14.
(respectful snip, I just wanted to reference your post)
Craig.

Originally Posted by wvu80 

Thanks, Craig, your explanation is exactly what I was looking for. I have read the manual as much as I can, but I really don't seem to absorb information from computer based manuals as well as I do the old fashioned paper ones.

Are the two different AVR pre-outputs there just to accommodate different sub inputs? I was thinking an LFE Low Frequency Effects was something specific to 5.1 setups, and would not transfer musical information the same way. (ie, explosions are not music)

Originally Posted by eljaycanuck 

You selectively omitted a key part:
And yet, after all that, and after all your subsequent insistence that you cannot recommend a subwoofer without fully concerning yourself with integration and room acoustics, you were nevertheless able to recommend an RW-12d. Funny.

Mr. Bman was making a recommendation based on my VERY limited 2 choices, a big, cheap, $300 Klipsch 12" sub or two smaller 10" even cheaper $120 subs, the latter which I can better hide from my wife.

Well, it's been fun and, thanks to Bill and Craig, a bit of a learning experience. I'm out. My apologies once again for the interruption. [/quote

No apology needed, I appreciate your comments and input.

Originally Posted by wlhungdude 

Hi Thomas,

Your question is a good one, but also a dangerous one. There is no end. If you upgrade to one subwoofer that rolls off at 18 hz, then you'll wonder what 2 will sound like... then you'll wonder what a 15hz sub provides... then 2... see where I'm going here? Have you seen the rotary sub that goes down to 3 hz? At some point, you just have to smile, and enjoy what you have.

Upgrade-itis. It's contagious, and this forum can infect you. Whatever you do... don't go to the DIY forum here

http://www.avsforum.com/f/155/diy-speakers-and-subs

.

Joseph