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yeah there are several very knowledgeable folks there. thy, jethro, warbleed, geolemon.. there are a few trolls too. average dispersal really. few very smart, few very dumb, and a lot in the middle seeking to learn more.

Mounting depth is about 8 3/4". Ryan, let me know if you are interested. This isn't a bash XXX thread, i just wanted to light a flame in the board, its been dead recently.

There are some fairly smart people around there. However almost all are arogant and very cocky/rude. A few smart ones that are nice.

Many idiots that dont do anything besides troll/harass people also.

It simply has a ton of members, but watching the forums for a few months will tell you they have a certain "base" members that form a "core" if you will.

I would say there are about 10-24 core members on the areas I frequent on that board. Seems some people are very teritorial on which parts they use, and which parts they are welcomed on...

Sure, your "lower Xmax" rated sub may be louder. But you apparently don't understand the context of what Xmax is.

Xmax is a measure of linear excursion. The XXX will have far less distortion at 32mm excursion than his "15mm Xmax" sub. But, you aren't comparing THD at such excursion levels. You're simply comparing max output, which is simply a matter Xmech (how far the sub can mechanically move).

Take the IA Death Penalty. Only has 19mm Xmax, but can really throw down in the SPL lanes. Why? Because SPL numbers aren't concerned with linear excursion, which is what Xmax is a measure of. There are some low Xmax subs that can move over 40mm before they start approaching Xmech. CV Stroker is another good example; only has an Xmax of 5mm. But, since SPL numbers aren't concerned with distortion, it doesn't really matter how much linear excursion a sub has.

Heck, the SX can get louder than the XXX. But that's not the point. David did a head to head test between all the RE drivers; same box, same car, same power; and the SX had the highest SPL number. But the XXX will have far less distortion anywhere throughout their excursion, because it has a higher Xmax.

Actually, I totally understand the content of what xmax is....

Justin from Detroit wrote:Actually, I totally understand the content of what xmax is....

So then why are you using Xmax in any kind of context as to your "SPL challenge"?? Xmax has nothing to do with sheer output, only linear displacement. If you wanna challenge Xmax, then do it properly by measuring THD, Bl & Kms curves, and not with a nonesense challenge that only proves SPL #'s aren't related to Xmax (which most people with common sense already understand).


Push them both to 32mm excursion, measure THD, the Bl & Kms curves and see who wins

ok what car/truck will you be driving i have to watch these people get beat.

I wouldn't call the X.X.X. overrated or labeled improperly, RE lists the specs correctly. The X-max of the subs have been dumax verified, XBL^2 is a very good design and provides what it promises. It is the person that interprets these specs that overrate a product, people that aren't aware of how a sub truly performs in a given application. RE didn't guarantee a decibel number that you would hit or that it would beat all in comparisons, they simply designed a subwoofer that they felt would perform well in the application it is intended for, and that is as far as they can go. It is up to the consumer to use a product to it's fullest capabilities. As far as the ultimate supersub, though, that's subjective, but I'm more of a SQ fan than SPL anyway so I don't necessarily want the absolute loudest sub out there, so that influences my opinion on it.

I agree that X-max is a specification that fools a lot of people, you must have excursion to have SPL, but how much excursion is what fools people. Many don't realize that you won't reach rated x-max in every application, or many applications at all, really. Just because it may not have been as loud ported vs. your Elevation subs (just as an example) doesn't mean it is overrated or incapable of achieving it's rated x-max, it would just boil down to the enclosure used, power applied, and frequency of the tones that were used when comparing the drivers. Remember x-max rating is achieved by measuring the difference between coil length and gap height, they didn't overrate it, they simply told it like it was, and you could verify that by simply measuring both. Linear excursion is different from an X-max rating, and in many cases they don't necessarily relate to each other. Like said above, it is the interpreter that takes that into consideration, not the company that designed the product. As far as the subs though, I haven't seen many car audio subs that can provide a BL curve as wide as XBL^2.

"So come on all you XXX lovers, step up. I'm not denying that RE makes good products, but I am stating that they are over-rated in many, many aspects. xbl2 is using 2 small voice coils and having two magnetic gaps, one at the
the top plate and one at the bottom plate, the theory is that you have use
smaller coils to have more effieciency, however, i feel that it has a lot of unsolved issues with out of the gap movement! this is why I believe the 32mm xmax rating is wayyy too high! The same motor structure is being used on Orion H2 subwoofers, and how many of them do you see at SPL competitions??"

XBL^2 was designed to provide a large BL curve into high excursions, but this was for sound quality purposes, not SPL. While it does aid SPL to an amount, it isn't the end all be all determining factor nor did Adire Audio or Resonant Engineering try to decieve you into thinking it would be. It was designed to provide a solid motor assembly that not only offered high linear excursion, but decreased production cost so that people could afford these woofers, particularly with a shorter top plate. It also added the benefits of an underhung design, which are low inductance and reduced moving mass, and the short coils and high linearity reduce cost again because you don't have to use dual spiders to achieve resistance to rocking, which again aided SQ the most, and SPL a little. I would think anyone serious about SPL competition from RE would be looking into MTs instead of X.X.X.s.

"Xmax is more then what you think it is, voice coil has a lot to do with how loud a subwoofer can get, too. The Pros, at full power, have almost 3" peak to peak, so xmax doesn't mean as much as you may think."

Peak to peak is less useful than linear excursion. Once you leave the magnetic gap you're losing tons of power to the driver itself, comparing linear excursion to mechanical excursion, linear will always win out, whether in SQ or SPL. I'm sure this is what you're basing the X.X.X.'s being overrated upon because of their loudness, be it metered, percieved loudness, etc, but really a sub won't reach peak to peak or full linear excursion very often when referring to SPL type enclosures such as ported or bandpass enclosures near tuning, or even sealed enclosures in many cases, especially when you're referring to powering it with near rated power. Excursion does help, but you have to match the suspension of the subwoofer to achieve that excursion, which is what SPL inclined subwoofers are designed to do. The suspensions of subs that do provide high SPL also tend to reduce SQ, which is a compromise that has to be made.

Out of curiosity, what were you using to compare the two, and what did both meter at in a similar environment, and at what frequency? It is well known that Brahmas and X.X.X.'s have a rolloff above 60hz, which typically is where cars reach their highest SPL due to cabin gain, that could have made a big impact on the tests you were doing, especially if using music like rap, rock, etc. and not test tones. Excursion doesn't come into play until you begin getting lower in the frequency range anyway. Even distortion can increase the percieved loudness, high levels of distortion are fatiguing and many interpret that as being loud. Just curious how far off they really were from each other, from a more scientific standpoint.

Justin, since you are so confident, you wont have a problem shipping me 2 12's to put in my car, with less than 2000 watts total. I don't have XXX's, but SURELY if they are that great they can beat two Stereo Integrity 12's. So, until you send out some subs, put up or shut up. PM me for the addy to send them to. I'll gladly return them after testing.

Justin from Detroit wrote:That's right, the XXX's are over-rated. Yes, I said it. On a board where every single "what sub should I get?" post immediately gets answered with "RE", I said it. Your precisious XXX's are over-rated, improperly labeled subwoofers.

you don't quite understand the specs, or the design of the XXX to be anywhere near qualified to make that statement... read on..

because xmax is a bullshit rating.

you don't understand it... read on

xbl2 is using 2 small voice coils and having two magnetic gaps, one at the
the top plate and one at the bottom plate

buzzer... 100% wrong... woofers using XBl^2 topology have 1 voice coil.. not 2... 1... using a split gap, via a notched Topplate and Pole..

since BL is simply flux times wire lenght immersed in it, its easy to see how this cofiguration yields a flat Bl curve...

oh wait... lemme explain it better for you...

if you have 40 feet of wire immersed in each gap (80 feet total), and you begin to move the coil forward, you lose wire in the bottom gap, yet gain it back in the top gap... say 50 feet and 30 feet, then you continue forward until the entire 80 feet of wire is immersed into gap 1... still the same amount of wire as it was at rest.... still the same BL spec...

since BL related distortion accounts for a BIG portion of the driver based distortion (Cms is the other big piece) you can see why flat BL is good...

wait... Cms = suspension :)

the theory is that you have use
smaller coils to have more effieciency, however, i feel that it has a lot of unsolved issues with out of the gap movement! this is why I believe the 32mm xmax rating is wayyy too high!

you don't understand how efficiency works.... do you :) think harder and get back to me...

The same motor structure is being used on Orion H2 subwoofers, and how many of them do you see at SPL competitions??

sorry.. its not.... orion uses a cheap knock off of what Adire came up with, and its a completely different, and much worse design...

while testing loudness holds value, you're proving basically nothing by doing a swap in and out and just testing output.... other than if that customer wants to drive around listening to that specific frequency, one driver is louder than the other...

however, the XXX will have FAR less distortion, at any output level, and that's important to non-spl competitors.... unless you like listening to crap... and you may...


btw.. Xmax is the LINEAR amount of one way travel a driver has....

its defined as "the shorter of the Xmag and Xsus values, in each direction of cone travel."

now since I doubt you know what xmag and xsus are....

xmag = linear travel of the coil to the point where BL has dropped to 70% of its at rest value...

xsus = the point at which the compliance of the suspension has dropped to 25% of the value at the cone's rest position...

as stated before, the XXX has a dumax verified xmax spec... if you don't know what dumax is, I suggest a short across town trip to DLC, and let Mr. Clark teach you...

and I bet if you were an RE dealer, you'd be singing the "this other woofer is crap song" because you're in it for the money, and considering the outreagous markup on your drivers.... well.... I can see why.... :)

fyi, I have a box design here that ultilizes 1 RE 8, with 400 watts, that's 1.2 db louder than any 12" driver in a basic 2.5 cuft ported box, with a 35hz tuning.. does that mean those 12" drivers are junk? nope... just proves if you wanna build a box that'll fart a high number, you can.... but you'd be a complete moron to drive around listening to that 8.... its louder at one frequency, and thats it... and it sounds like crap doing it..

and finally, since I think you're in severe knowledge lack about motor topologies... I have a post I made that'll help you out..

http://www.splbassx.com/forums/index.php?showtopic=4654

toodles

Loyd L.