...got bass?

[rigtec]

Blown one W3 so far with the amp at 1/2 gain. Think I might hit up a W6

Hi BowJanked,

Yeah, the W-3 series is kinda like the Lexus 350 series or the BMW 325i; much lower build quality but wears the same badge for those into the status game but can't afford the real deal! The W-6, now that's a whole different sub! If possible, you can try to find a W-6 vers 2. If you analyze the specs/parameters, the Version three doesn't really supersede or improve on the sub's capabilities by a measurable margin; at least not by enough to justify those $500 (plus) price tag. You can find a W6-v2 for $300-$350 (new) and it is capable of the very same amount of apparent volume output as ver three!

Cheers

 

[BowJanked]

Hi BowJanked,

Yeah, the W-3 series is kinda like the Lexus 350 series or the BMW 325i; much lower build quality but wears the same badge for those into the status game but can't afford the real deal! The W-6, now that's a whole different sub! If possible, you can try to find a W-6 vers 2. If you analyze the specs/parameters, the Version three doesn't really supersede or improve on the sub's capabilities by a measurable margin; at least not by enough to justify those $500 (plus) price tag. You can find a W6-v2 for $300-$350 (new) and it is capable of the very same amount of apparent volume output as ver three!

Cheers

Yea there 650$ where I live for a W6 gonna have to save up for a bit

 

[rigtec]

Yea there 650$ where I live for a W6 gonna have to save up for a bit

You mean the W6-v3 costs that much, or the v2 and I was running four in one box? That's far more than I've ever paid for a W6-v2. JL and Crutchfield will try to get that much for that sub But if you shop online e.g. ebay, amazon... you'll pay half that!

Never paid more that $350 for these unless they were boxed!

 

[BowJanked]

You mean the W6-v3 costs that much, or the v2 and I was running four in one box? That's far more than I've ever paid for a W6-v2. JL and Crutchfield will try to get that much for that sub But if you shop online e.g. ebay, amazon... you'll pay half that!

Never paid more that $350 for these unless they were boxed!

I'm in Canada

 

[rigtec]

I'm in Canada

Oh, I get it... S&H issues. Do you like to travel lol!!

 

[BowJanked]

Oh, I get it... S&H issues. Do you like to travel lol!!

Cost more then it's worth most of the time. Grrrrrrr

 

[rigtec]

Cost more then it's worth most of the time. Grrrrrrr

You know, JL's are NOT the last word on subs, nor are they the supreme choice in subwoofer technology! There are other brands with the same level of quality but with a less ominous name! JL has become a status symbol; even though I give them credit for some of their own proprietary developments! If you're not bent on their name, shop around for newer name exceptional drivers that have incorporated some of modern technology's best developments!

Even I (once a die-hard JL advocate) have switched from JL to Alpine because they've not only borrowed some of the available improvements in subwoofer design, but have also developed a few of their own patents; and they're a lot cheaper. So don't be afraid to experiment with different brands! Rgds!

 

[BowJanked]

You know, JL's are NOT the last word on subs, nor are the the supreme choice in subwoofer technology! There are other brands with the same level of quality but with a less ominous name! JL has become a status symbol; even though I give them credit for some of their own proprietary developments! If you're not bent on their name, shop around for newer name exceptional drivers that have incorporated some of modern technology's best developments!



Even I (once a die-hard JL advocate) have switched from JL to Alpine because they've not only borrowed some of the available improvements in subwoofer design, but have also developed a few of their own patents; and they're a lot cheaper. So don't be afraid to experiment with different brands! Rgds!

Been using JL since 1997. Always liked them. Also won a few comps running Type R 12s.

 

[Superjet]

You mean the W6-v3 costs that much, or the v2 and I was running four in one box? That's far more than I've ever paid for a W6-v2. JL and Crutchfield will try to get that much for that sub But if you shop online e.g. ebay, amazon... you'll pay half that!

Never paid more that $350 for these unless they were boxed!

Ya sorry, but that looks like 90 degrees out of phase. Ditch the top subs.

 

[rigtec]

Ya sorry, but that looks like 90 degrees out of phase. Ditch the top subs.

Low Frequencies are 'Omni-directional' as are the drivers that reproduce them... which is why you only need one in your home theater stereo or surround sound system. I'm kinda surprised that anyone would instruct that kind of 'unsolicited' advice without knowing that, or first asking if I was having any trouble with P/C. You can face your subs in any direction preferred (even in a 'Clam-shell configuration') and experience no combined destructive sound anomalies at any time 'as long as the drivers are identical'.

'Best to you'!

 

[rigtec]

Hey gang,

There was a new member (a gentleman), who posted a comment about one of the subs that he saw in one of my photos (which I just became aware of) that may have others confused. His theory is, it seems, is that if you need to face your multi-driver subwoofers in different directions of one another, then you'll somehow be creating some sort of low frequency anomalies that will combine destructively. So I just want to set the record straight for those of you who will be building subwoofer systems in your own 4Runners that, due to space constraints, may need to arrange the drivers around the box; this is perfectly fine!

As long as the inner chamber of your sub is large enough to provide the manufacturer's recommendation for adequate inner box volume for each driver... and all of the drivers specs and operating parameters are identical, you'll NEVER have a problem with regard to your speaker angles. Below, I have posted pictures of one particular audio engineer's HUGE infinite baffle "Eight eighteen" subwoofer design for his home theater system; have a look:

Because the backwave of the drivers MUST BE kept completely separated from the frontwave (or they will cancel each other out), he's venting the frontwave into his backyard but the rear wave is channeled into his H.T. room via a louver grille behind a bookshelf... you can read all about it in this link: Infinite Baffle Subwoofer

If this thread started off as my question about subwoofers or car audio bass speakers, then it wouldn't matter if some (well meaning) individuals posted their uninformed opinions about what they heard that someone told somebody else; happens all the time. But the objective of this thread is to properly inform others about low frequency systems, explain some of the design theory or physics involved that work for and against us, and to dispel some of the wive's tales, myths and folklore that is flooding our airwaves these days; mostly by the marketing agents and manufacturers, hoping to exploit the uninformed.

I truly hope that those of you who may have an interest in bass systems or subs will read William Cowan's design theory papers on the subject... it's a very interesting read even if you don't understand everything that he has written about in the link posted above! Well, that's it for now folks... keep having fun with your own audio build experiments and please be sure to post your own audio system build threads (with plenty of photos) for the rest of us to benefit from!

Cheers!

 

[tigger]

That just does not look like an effective design. I guess at home theater volumes it would work, but it would seem to me that pushing any power to that box would create a vacuum when the woofers were trying to extrude. (unless the box is vented.

Eight 18" drivers move a lot of air and it would seem like all eight trying to move at the same time would actually limit how far they would travel. Maybe not though. It could be the box is big enough to supply air space for all of them, but I would have tried to isolate at least each pair to reduce back wave resonance in the box.

And with no internal bracing, that thing has to have some serious flex.

I bet it rumbles his house though :music:

 

[rigtec]

"That just does not look like an effective design. I guess at home theater volumes it would work, but it would seem to me that pushing any power to that box would create a vacuum when the woofers were trying to extrude. (unless the box is vented..."

Hi tigger,

This manifold hits 130 dBs @30hz and is hugely efficient at that frequency range; I have two of those "Eighteen Sound LW-1400 18's in my stage folded-horn bass amps. These drivers are designed to be used in BR alignment, sealed environments, or I.B. (Infinite Baffle) manifolds. This means that the driver can work in a "Free Air" (Half space) environment... like cutting a hole in your attic floor to mount the driver (magnet end up) and the front of the driver (cone side) is in the theater room ceiling! As a result, this design can go extremely low because the cone has nothing to prevent it from excursing it's full mechanical limits (X-mech) so the power provided must be governed very closely by the audio tech and the compressor or the limiter in the input signal.

The system pictured above is such a system. The Back-wave (actually the front side of the cone seen outdoors) is vented away from the house to prevent any interaction with the front-wave (actually the magnet end of the drivers); which is the business end of that sub in this case and through a short duct, goes through a louver vent into his theater room. But even when operating in a sealed environment, you have to remember, the pressure, that you referred to as a vacuum, is depended on to keep the drivers from self destructing by over excursion. The same force that they produce when creating low pressure in a sealed box (when moving outward), is then creating high pressure when moving inwards; which again is a part of the sealed box design... the sealed box increases it's power handling capability and helps to flatten the frequency response for a smoother, tighter bass.

Every alignment has it's own special area of superiority. The bass reflex is the most efficient but the the sound quality will suffer. The I.B. will likely go the lowest but it's power handling capability will suffer. The Sealed box exhibits the smoothest frequency response, but it's maximum dB output will suffer due to it's poor efficiency. And the band-pass alignment will have the strongest low output... but in only one narrow pass-band (affectionately known as 'The one note wonder' as a result of it's extremely narrowed bandwidth due to it's design and being a resonator; it doesn't develop very much sound output until the tube begins to resonate at whatever frequency it's tuned to!

Cheers!

 

[flyinhawaiian01]

Its interesting to read about stuff like this, there are so many designs that just don't look "proper" that folks would think that it would not work correctly! Take an 8th order bandpass box, that alone should say that the front and rear soundwaves should cancel one another, but it actually amplifies the signal due to timing of the waves!

Now, if this box was sealed with 4 subs positioned like that, I would think that there would be some SERIOUS vacuum/pressure in that box, enough to damage the speakers themselves as they're fighting the pressures while each speaker moves forward/rearward! But, because the designer built the vents to the side(s?), pressure moves freely within the enclosure and allows the sound to be expelled by the cones. What interests me is that he has it OUTSIDE of the home! That means there is a good amount of sound outside too, I'm sure if his neighbors are even remotely close, they will hear that quite clearly for a good quarter mile away at 130db!!!

As for your box with subs above and facing rear, there is a possibility of sound cancellation between the two sets, but one would also have to take into account the timing between the sound reflecting off the rear as well as the roof of the vehicle, and while sub bass is mainly non-directional, you could possibly amplify or nullify the bass just by moving the placement inches back/forward, as well as tilting the sub too. I know for many subs that I've worked with over the years (many of them 4th order boxes, I do like the versatility and ability of lower frequencies of the design), if I have the sub firing at a panel, if I move it slightly away, or sometimes closer, the bass is "directed" in the cabin where you get a null or overamplified signal sometimes.

This is part of the fun with subs though! [MENTION=120209]tigger[/MENTION] has done a TON of subs in all the vehicles he's owned (I've been lucky enough to experience many of them!), and we all have found that some subs work much better than others in the same vehicle, depending one where its placed and what type of enclosure is used. Might I add, almost every one of his systems have been top-notch in build and sound quality!!! And if its not perfect, he's anal enough to go back and re-do stuff until it sounds fantastic! :eyebrows:

One of my favorite things I used to do was to install a 6" 4th order sub in a customer's car and let them hear the difference of it against 2 8" subs! Most folks never understood how such a tiny box could create so much more bass than their 2 speaker subs that were larger in size!

Of course, I never told them about the fact that they work with a smaller frequency range! Luckily, most folks who look for big bass only want that 30hz boom, which is where the 6 and 8 inch 4th order boxes really come alive!!!

Keep rockin' Rigtec! Keep disproving those myths of what folks think won't work properly with real-world, firsthand data!!! :rockon:

 

[jwatson]

This thread is so great, thanks!

 

[Superjet]

Low Frequencies are 'Omni-directional' as are the drivers that reproduce them... which is why you only need one in your home theater stereo or surround sound system. I'm kinda surprised that anyone would instruct that kind of 'unsolicited' advice without knowing that, or first asking if I was having any trouble with P/C. You can face your subs in any direction preferred (even in a 'Clam-shell configuration') and experience no combined destructive sound anomalies at any time 'as long as the drivers are identical'.

'Best to you'!

If you place one sub facing another sub that would be 180 degrees out out phase, and the sound pressure cancels each other out. Same thing with 2 subs side by side wiring up one reversed positive/negative. The sound waves cancel each other out. Remember, subs more or less push air pressure.

This isn't unsolicited advive either, you can find my name as a contributor in both basic and advanced MECP books.
You want to have multiple subs working together

 

[BowJanked]

Wow that escalated quickly. Great info. On a different note I blew yet another 12W3 [emoji35] so not happy. 12W6 time.


Sent from my iPhone using Tapatalk

 

[tigger]

If you place one sub facing another sub that would be 180 degrees out out phase, and the sound pressure cancels each other out. Same thing with 2 subs side by side wiring up one reversed positive/negative. The sound waves cancel each other out. Remember, subs more or less push air pressure.

This isn't unsolicited advive either, you can find my name as a contributor in both basic and advanced MECP books.
You want to have multiple subs working together

If you place one sub facing another that is an isobaric configuration and is not out of phase as long as they are wired correctly. If you mean facing each other from a distance they would only be out of phase if you reversed the polarity on one driver so it was moving in as the other was moving out. Then you will have cancellation the sound waves.

His subs were rear firing and top firing, and there is a variance in the distance to each surface plus a variance in the shape of those panels. Although the sound waves may collide at some point, they will not cancel each other out. The wave hitting the tailgate will reflected down then up to the ceiling. By that time the top firing drivers sound waves would be hitting the ceiling then reflected forward because of the sunroof contuse.

 

[rigtec]

If you place one sub facing another sub that would be 180 degrees out out phase, and the sound pressure cancels each other out. Same thing with 2 subs side by side wiring up one reversed positive/negative. The sound waves cancel each other out. Remember, subs more or less push air pressure.

This isn't unsolicited advive either, you can find my name as a contributor in both basic and advanced MECP books.

C'mon, you're kidding me right? this is a ridiculous statement!

First off, I didn't solicit your advise on anything so how's it not unsolicited? ...And secondly, If this is the kind of information that you're passing around in all those those books you mentioned then perhaps you're in the wrong field. This is the kinda stuff that we who 'actually study' Pro-Sound Audio call "Snake Oil!" There's plenty of accurate information out there to be learned but based on your post it would appear that you've missed the boat! I'm only posting one link below because I shouldn't even have to take the time to correct a self proclaimed "professional instructor". ...For those of you who are interested in the subject of 'low freq driver coupling' there thousands of threads online that you can learn from!

Sonnie
HTS Hillbilly
HTS Administrator
There are numerous choices in how you might install your drivers in an IB system. Below is merely a few various examples of manifolds and line
arrays that are attached to floors, ceilings or walls. (This is an excerpt from the engineer's thread. To read his article, Please see the link provided below) *PS: All of the speakers pictured below are low-frequency drivers and subs and are arrayed at different angles for where space constraints are an issue!* ...and no destructive phase anomalies with any of these designs!

"If what you say were true, these subs wouldn't be Thee' Industry Standard for Low-Frequency pro-Audio systems!"

Engineer's link>>Weiterleitungshinweis

Cheers

 

[rigtec]

If you place one sub facing another that is an isobaric configuration and is not out of phase as long as they are wired correctly. If you mean facing each other from a distance they would only be out of phase if you reversed the polarity on one driver so it was moving in as the other was moving out. Then you will have cancellation the sound waves.

His subs were rear firing and top firing, and there is a variance in the distance to each surface plus a variance in the shape of those panels. Although the sound waves may collide at some point, they will not cancel each other out. The wave hitting the tailgate will reflected down then up to the ceiling. By that time the top firing drivers sound waves would be hitting the ceiling then reflected forward because of the sunroof contuse.

Hi tigger,

What you're saying is exactly true; I couldn't have said it better... but we're talking about two very different things! What you've focused on is what can/may happen AFTER the low frequency wave-front leaves the box. Gotta remember: We're talking about wavelengths of over the length of two 4Runners e.g. 50 hz has a wave length of 22.5 ft, 40 hz 28 ft, 25 hz 40 ft. So when you have a sub that is utilizing (Identical) multiple drivers, the sound wave coming off of the driver cones will actually believe that it's just one cone that it's radiating off of (no comb filtering in very low frequency boxes). We're only talking about a couple of inches between the driver cones; relatively too small a distance between drivers for the huge soundwave to perceive, and so driver coupling (multiple drivers working together as one) takes place.

And low frequency waves aren't directional; they envelop the listening space in a circle relative to their box source. In my case, when I was using the four ten sub, I never had a problem with phase issues; positioning (as you have referred to) can be a challenge sometimes because of reflected soundwaves hitting the walls, windows and ceiling then coming back to the box at different times; no way to control that unless you're willing to insulate every hard surface (including window glass) in that listening space. Recording studios do that for that reason, and to keep the sound leakage to a minimum in both directions (in and out). Thanks for your post and sharing your experience with the rest of us!

Best to you