Official Epik Subwoofer Thread - Page 9

The eD sub is still a work in progress ... I cannot get it into our theater room without a LOT of help. It is huge and weighs 435 pounds. Beast is right ...

Once again, there is a good possibility that you are right about the BMF.

I just have this annoying habit of wanting to actually TEST a product before declaring what its performance is.

A prediction ... I test a BMF against a Conquest. The Conquest "wins". Someone will then tell me how I said the BMF was going to win, and that I was wrong, again.

Anyone want to take this bet ?

Maybe, since no one has measured a BMF, and unless I missed something there aren't a bunch of similar designs out there to benchmark the BMF from. But you go right on with your paper racing.

Yes, cause we all know size, appearance, distortion and other sound quality characteristics are completely unimportant for subwoofers. Only SPL and extension matter.

Perhaps you can further explain yourself. A bandpass works with Helmholtz resonators. Both ports and passive radiators are Helmholtz Resonators. How does the presence of a port on the Conquest automatically seal it's victory?

Look, I'm not saying the Conquest won't have or can't have more output than a BMF, or that it can't play or won't play deeper than a BMF. All I'm saying is that it seems everyone is assuming an awful lot about the performance of a rather unique product.

The BMF is clearly not in the same "category" as the PB13 and the Fathom either. Mark Seaton's Submersive-1 is about par with JL's Gotham, not Fathom, (per his comments), and Mark has stated that the BMF will have quite a bit (~6dB if I'm remembering correctly) of additional output over the Submersive-1 below 30Hz until you get below the tuning point of the BMF. So the BMF should have no problem walking all over the PB13 or Fathom. But you just keep making your assumptions and mischaracterizations of the BMF while some of us wait to hear one.

See!, I can paper race too...

By category, he simply means smaller-driver subwoofers (or non-18" high-excursion drivers). In which case, the BMF is, even if it has more output than a Fathom (easy) and a PB13 (remains to be seen). I would say, down low, the PB13 and the BMF will be pretty close in output, however, the passive radiator reproducing the high-end, should give the BMF an advantage, up high.


Because it guarantees higher low-end output. We know the Conquest uses a high excursion 18" driver. The best the BMF can do is a high excursion 15" driver (it could be moderate, we don't know). There's no way that the BMF will improve on SPL over the Conquest. It's a simple matter of physics. Now, considering the passive radiator, reproducing the high end, of the BMF can trap distortion products from the 15" driver, it's quite possible it'll perform better, overall. But, it won't be able to perform better, down low, where displacement rules the game.


It's only unique in application - low-tuned high-excusion drivers. It models similarly to a 6th order bandpass design, which is certainly nothing new - it's based on an expired Bose patent from the 70s(?). It gains a few dB over a simple 15" ported subwoofer up high, but this isn't anywhere enough to make up for the difference in displacement from an 18" driver driving a port, down low.

Whoa whoa whoa, Stereodude there's no reason to be offended. I own an AV123 Rocket set, but lets not lie to ourselves here.

The BMF is a product geared to a specific consumer. None of the subwoofers we've mentioned look anywhere near as good. No one here is saying its incapable or underdelivering. What everyone here is stating is that the BMF
1. on paper
2. when it comes to extension

is NOT going to perform as well as the Conquest. Hell even Craig believes so and everyone respects him.

The Conquest is a subwoofer that looks amazing on paper. I haven't measured it- but I do own an Avalanche 15- in a 6 cu foot box and I know the history of this company. If this driver is better than the Avalanche, fits in the proper sized box, and has proper amplification - the numbers Chad is quoting are not unreachable. The fact that we are all gushing about is the price of this type of performance. Kind of like the same thing that happened when AV123 first hit the scene and the 750s retail for 1399.

Here is what Mark Seaton had to say about the BMF and Conquest:

I'm neither offended, or lying to myself. I'm waiting to hear one before forming my opinion.

Mark Seaton seems to disagree, but apparently his opinion doesn't count by your tally.

Well I guess the BMF is going to shock a lot of people when it comes out if you're expectations are so low. The BMF has 2 18" passive radiators pumping out the low end displacing air and you think it's tied with a 13" driver and a port.

Clearly you don't understand those physics nearly as well as you think you do. The 15" driver in the BMF doesn't directly dictate the performance because it's inside the box. It doesn't matter how big it is or how much it moves. What matters is how much the passive radiators on the outside move. They dictate the performance, and last time I checked the BMF has more moving surface area than the Conquest, but you keep ignoring that.

How do you know how it models? Has Mark Seaton shared the models with you? Futher you don't really seem to know how a bandpass sub works. Yes, there's passband in which the has better performance. The passband is not necessarily up high. The pass band can be at the low end too. If Mark is worth his salt as a designer (and he most certainly is) the passband is at the low end.

Hi Guys,

I'm not here to threadcrap on sherv's/Chad's party here, but I did think I should jump in to correct a few points.


Hi Seth,

There hasn't been a lot of info on the Gotham's acoustic performance, and all of the comparisons I've made with the SubMersive are more to the Fathom F113. Above 40Hz the SubMersive might not be far off a Gotham, but power and box size still set certain practial limits.

Before I add any more, know that Chad K, & I are acquaintances from long ago in our DIY adventures before either of us were "in the business." Chad has probably built as many large vented boxes as anyone I know, and I expect the displayed Epik products will be prodigious performers. Personally I like that his offerings add another set of characteristics to the list of subwoofers that deliver the goods as compared to the options retail consumers usually are exposed to. I think it's a great thing for the market that we begin to have more capable options so we get start to get past the basic need of reasaonable LF output.


Hi Lindahl,

In any reflex system (which the low end of the Conquest and BMF both are), the displacement of the driver is rarely the dominant factor, as the resonator (Port or PR) does the legwork around the low frequency tuning. System efficiency and resonator capability usually determines what is more effective around tuning.


From the perspective of a black box analysis, both the Conquest and the BMF use a reflex loading at the low corner. As frequency raises, both subwoofers use an 18" cone to produce acoustic output. That acoustic output comes from the 18" cone's displacement. It' doesn't matter if the cone is directly driven with a voice coil or if it's acoustically coupled to an internal driver, X distance of fore-aft motion produces Y dB SPL at a given frequency.

Chad,

I'm sure that a few of us would like to know what the tune of the Conquest is (if you don't mind divulging that info)? And what it could be lowered to by plugging one port? I know that the one port would get overloaded, but I wonder what kind of useable extension this would get you for "moderate" listening levels? Any thoughts of including port bungs? Are there any plans to release the driver from the conquest in a smaller sealed app?

Keep up the good work, these subs look like first rate performers, and I'm actually starting to rethink whether I want to spend the time to DIY my next subs now.

Sorry but I don't agree. The BMF has three 18" passive radiators which produce the output. The single 15" is there just to excite them, so to speak. So anywhere above the tuning frequency the BMF has probably more (we don't know the maximum excursion for any of these drivers) displacement there (at least more cone area). Around the tuning it will be dual 18" PRs vs. two 6" ports. I would say it will be a tough call.

My mistake... Maybe I was thinking of a pair of F113's. Either way the BMF should have no problems outclassing a single Fathom F113, which was my point.

Not to thward the attention, but what is the price expected on the bmf? It looked like someone mentioned 2k but i'm not sure. Given the size/look and possible performance that may be a great deal.. The new price of the conquest though is a fantastic deal. Man this is going to be a tough decision.

Yes it's $2000.

More info here: http://av123forum.com/showthread.php?t=13824

oooooh, look the epik store is back up..
Hey chad, can you give any kind of comparisons between say the valor and the knight in terms of performance? I'm really hoping to see these get tested soon.

Yes, but the passive radiator is being driven by the excursion of the 15" driver. When the 15" driver starts to give up, the movement of the passive radiator is affected, as well, no? The same way a driver's performance can be limited by it's voice coil capability, no?

You can't just ignore the excursion of the 15" driver. Sure, it'll exert less, given that two passive radiators alleviate the low and high end, but you're still limited by the excursion of the 15" driver in the mid-low end of the passband (25hz?), and it's 2nd and 3rd order distortion products will also drive those passive radiators (higher order is limited by the upper Hemholtz resonator), along with movement limitation of the passive radiators when the 15" driver starts to compress.

Low-end performance in a reflex system is limited by the performance a bit above tuning. The bass reflex 18" driver's low-end limitation also lies around these mid-low frequencies. Since both subwoofers are limited by the driver's excursion in the same region, the 18" driver, having more displacement, will also have more low-end performance, since it's limited less than a 15" driver.

Am I wrong here? Maybe I was misunderstood, before?

Oh, and Mark, do you mind sharing the upper-end limitation of the BMF? Where it begins to roll off?

Indeed it is back up! This looks good right here:

"Tower specs:

* Price: $1099 - Textured black
or
$1299 - Rosenut veneer"

$1299 for a high excursion 15" ported sub with a (what should be) a nice looking veneer? Nice.

$400 less than the PB13 for the black finish and $300 less than the PB13 with the veneer. I just love competition.

Oh, you're definitely wrong.

This is pretty funny... You're lecturing Mark Seaton and telling him where he's wrong... This must be the very definition of irony.

Your problem is that you're assuming there's a 1:1 relationship between displacement of the inner driver driver and the displacement of the outer passive radiators. This is not the case due to resonance.

Looks like they just have the textured black for now. Man I was just ready to pull the trigger on a PB13 but now I'm really thinking about that Conquest! Same price but much more powerful. I think it might be an overkill for me. I'm sure I would be extremely pleased with either one though.

No, I'm not telling him he's wrong. Nor am I lecturing him. I'm telling him what I know to be true and asking him if it is, or not, and why I'd be wrong. I'm trying to learn here, and you're just getting in the way, pissing around. You can leave at any time.


No, I never assumed a 1:1 relationship, but neither are resonators 100%/0% devices. I said the distortion and compression at the point in which the 15" driver is working the hardest (in between the two resonances, biased heavily towards the lowest resonance), will definitely affect the movement of the passive radiators. To assume you can just throw the 15" driver into over excursion, without reprimand, would be a mistake, and I doubt Mark is doing this in the BMF, especially looking at the 1000 watt amplifier.

With bass there is no such thing as overkill. Your only constraints should be budget and size of the enclosure (And the aesthetics to some degree ).

Lets do not pit a product that was not released to an existing unit in production(Conquest).

For me it will be Conquest,Ultra13 and big ED and BMF....These little fights are hilarious,just buy the sub that suits your budget and performance expectations.




BMF,the design is unique,I can tell you this type of design even with a 15" woofer capable of "only" 1.5" Xmax will have tremendous output(3 18" PR's will move far more air any 15" woofer can(even at 4" Xmax).

Any good pics of the Epik subs? Not from there web page. The pics aren't very good. In home with someone who actually has a good camera
Does anyone have anyone of the lower end subs that can give the opinion on sound quality??

Have you tested that though? forget theory and plotting... real world testing.
In my test's one big port is always louder then multiple small ones even if tuning is the same and if port area is the same. I remember gaining 1 db going to 1-8" port from 4-4" ports Where do I get big ports from well I make them . Plotting predicts the spl will be the same but in my real world test's in multiple box's 1 big port is always louder. I myself haven't tested PR's so for all I know they could be just as loud as a port or louder or not as loud who knows....

Its not overkill when you wanna play 10hz at a moderate volume . A pair will insure you to get something at 8hz!