First DIY project for a guy looking to upgrade - multiple sealed 18s? - Page 15

Bosso, are you basing the above comment on the published xmax of the Dayton? Eventhough Ricci noted approximately 20mm of usable xmax on the HO after independent testing? That obviously has to be the case given the UXL isn't capable of 60mm of xmax.

Gorilla83,

The flat packs for the single Daytons should be done this upcoming week and I'll be ordering shipping boxes.

I'm working on a dual opposed cabinet for these as well. Do you think they should be mdf, Baltic birch, or a domestic birch plywood?

The domestic birch plywood would be lighter weight for shipping. Maybe not as strong as Baltic birch, but still as strong as most other plywood anyone would use. I'm not sure what type of plywood you used on yours or what the end weight was.

MDF would be cheaper, but more expensive to ship due to the weight. All of these large dual opposed flat packs will need to be shipped in 2 boxes anyway.

Erich, if you do BB can you make sure it's void free.

the results are cea max burst for the drivers. push two drivers to the same limit and you get +6db. uxl does not have 3x the displacement.

What's the volume of the single driver box? How much are you planning to sell these for? If it was discussed elsewhere I'd appreciate the pointer.

Thank you

Whatever the CNC company quotes, plus packing material, plus Paypal fees. Once these come in, I might need help boxing them up. I asked a friend if he would help for $5 per sub package.

The single box is about 4 cuft. Dual opposed was 7. That's what most people thought would be best.

Awesome. Would it be reasonable to expect the price to be close to the 4.5 cu ft pack you are selling? I am just trying to ball park it.

I'm basing the conclusion on output. But, the output differences in Josh's results also just happen to correlate closely to the ratio of difference in both drivers published X-max #s.

At 20 Hz, 16 Hz, 12.5 Hz and 10 Hz, the UXL gives +5dB more output, which has nothing to do with X-max and everything to do with displacement.

Whatever the 2 drivers actual X-max is, whether those #s are based on the VC overhang or 70% * Bl, the UXL equals 3 Daytons in dBSPL, which translates directly from throw and does not necessarily translate to X-max.

Why would someone who gets two HO drivers not double the power for 6 dBs of output? Why would they not add power when adding another driver? You can run 8 of these on one clone or 4 of the UXL's and won't you get the same spl at 10hz to 16 hz?

"Whatever the 2 drivers actual X-max is, whether those #s are based on the VC overhang or 70% * Bl, the UXL equals 3 Daytons in dBSPL"

that is incorrect. backing out the numbers from ricci's test results, the uxl has a burstable aes excursion at 20hz of around 44mm and the dayton has about 23mm or so.

also, you are confusing sensitivity with excursion limited results.

two drivers driven to the same excursion limit give +6db. always has, always will.
Edited by LTD02 - 11/25/12 at 6:25pm

"Why would someone who gets two HO drivers not double the power for 6 dBs of output?"

that is a tricky question to answer mk. the simple answer is that you should.

the more complicated answer arising from the bosso-ricci bet is that the uxl and the ho drivers have pretty much the same sensitivity in the test enclosure at 20hz. 1 driver for 1 driver.

1300 watts takes the dayton to its limit.

the uxl requires something like 5000 watts to get it to its limit, but its limit is about 6db higher.

add a second dayton and another 1300 watts and you get a hair higher spl at 20hz than the uxl with 5000 watts.

so the uxl requires 5000 watts, while the dual ho rig requires half that for the same spl at 20hz.

how is this possible? it is from the +3db increase in sensitivity that comes by doubling drivers, which means that you need half as much total power for the same spl.

More confusion.

A 120V 20A clone would give 300W per driver, so no, what LTD is suggesting is an amp for each driver.

Let me repeat: a UXL has the displacement of 3 Daytons. So, no, the 4 UXLs wins. That's what I said originally, the test results confirm it and LTD is building subs with a pencil again.

Gorilla uses 1 amp (and it certainly isn't a K-10 amp run off a 220V 50A home run), not 4 amps.

As LTD02 mentioned, with two drivers and doubling of power the HOs would still use use only 52% percent of the power required to get full output from a single UXL.

It seems to me that power limited tests would put the UXL in a distinctly disadvantaged position.

Is there a way to model how a single UXL and two HOs would compare if powered by 2000W amplifier for example?

I just don't understand at all. I know you only get 3 dBs of output with doubling the drivers but why would you not double the power because you can? Basically the UXL with max power will hit 92 dBs at 10hz and dual HO's with max power will hit 92 dBs. It takes the UXL more power to get there. Max testing is max testing. This is the same reason why we like the UXL compared to the LMS 5400 driver, you get enough power and dual drivers and you will exceed the LMS 5400's. If ricci runs duals with his same amp will he not get 92 dBs at 10hz? He will only get 89 dBs and need one more driver?

"Let me repeat: a UXL has the displacement of 3 Daytons."

repeat until you are blue in the face. it is just plain wrong. maybe it would help more if ricci posted ricci's data for you?

the bet was two ho's vs. one uxl. you said the uxl would stomp them. as it turns out, the ho's produce more clean spl as per ricci's measurments.

"Is there a way to model how a single UXL and two HOs would compare if powered by 2000W amplifier for example?"

sure. the dual ho's are 3db more sensitive at 20hz, so watt for watt they will have a 3db advantage until you go past the halfway power mark of the uxl, which is somewhere around 2500-2600 watts or so (aes max bust, not sustained). at that point the ho's are hitting their excursion limit, so they are done. the uxl however can continue to be powered up to the 5000 watt mark or so filling in the last 3db.

so, at 2000 watts, the daytons would have a 3db advantage.

Rilla keeps his HO's in line!

thank you

"LTD is building subs with a pencil again."

spl relative to volume of air moved has been empirically investigated. winisd and linkwitz's spreadsheet both show similar results.

here is what linkwitz uses for excursion limited spl:

dB SPL @ 1m = 94.3+20*LOG(xmax in mm/500)+40*LOG(frequency in hz)+40*LOG(piston diameter in mm/1000)+6

(the +6 at the end is for two pi space)

it is not possible to get the spl that ricci measured with the dayton ho spec of 12mm xmax. you need about 23mm each way.

also, the uxl has usable excursion out past its xmax rating. i calculate it to be around 44mm.

so, two drivers with pretty much the same sd. the ho has 23mm one way usable excursion, while the uxl has 44mm. that is why the dual dayton wins by a hair at 20hz. they move just a little bit more air.

It's like the SI thread all over again. Unbelievable...

No. This thread has actual progress in it with happy customers using finished products.

You can ignore the side conversation(s), easily.

Bosso, I'm not sure I'm following. I know how to read Josh's results on DB.com and everything I've known about acoustics lines up with LTD has said. My math shows that two 18HO's in two enclosures would nearly equal one UXL/LMS-U in one enclosure. I'm not saying you're wrong or lying but I'm just trying to figure out where you're getting the numbers from. What I do know is that the UXL/LMS-U drivers on their own are much more capable than a single 18HO but I think we all know that already.

I'm at a loss. I don't understand why you dislike these drivers. They aren't displacement champions but they aren't exactly expensive either. Used in multiples they can acheive great bass output, SQ and extension. We all know that is the direction to bass bliss. I have to say I've lost the thread here on why you aren't at least giving them the 'ok' even if they aren't your style.
Edited by Scott Simonian - 11/26/12 at 11:25am

^^^ and like a ton of other threads. Lol. Why the surprise? This is what happens here--a forceful statement of competing arguments. As long as no names are called or blood drawn, there's nothing wrong with it. I, for one, am reading with great interest. Like, the OP, the UXL is on my radar, but the HO and SI offerings seem very attractive. Can't wait to see the in-box measurements of the SI to compare apples to apples.

Unfortunately this noise is polluting another thread, and when I get an email notification it's hard to tell if it's legit until I read it. Sadly, most of them of late haven't been.

Wouldn't it be better to start a new thread to debate all of this instead of it being posted all over the place in other peoples threads? If the arguing does eventually produce something of value you can simply post a link to the conclusion, thereby saving the rest of us having to watch it play out in public. Andrew has made it clear which direction he's going in, so why bloat his thread with something he's obviously not interested in? Maybe it's just me, but I don't see the value.


The UXL is not on his radar though, and he said as much three posts above yours: "The UXLs for me are officially out of the picture guys". That's why continuing the debate here makes no sense to me - it's not part of this build, and it never will be.

This is the nature of threads in the DIY section. OP asks about a JBL driver. someone mentions an Alpine alternative, and awaaaay we go. They spring up organically. For me, and likely many others, good information comes out of these disagreements. It's the nature of the beast and given that the discussion is directly related to the 2 different drivers the OP considered, it is very informative to those also considering those same drivers.

My 2 pence.

ordered a EP4k today. walmart.com of all places has them on sale. Erich said the boxes for singles should be ready for ordering in a week or 2

someone is prob getting me a driver or 2 for xmass

gonna be hard waiting a month for these

That is hilarious! I had no idea...wow, Wal-Mart?!? lol. That's a killer price too...ships free to store as well. Nice!