New Dayton Audio Ultimax 15" Subwoofer at PE - Page 2

Ignore my ramblings above. I went back and double checked and had somehow put the listening position at 3m instead of default 1m for the LMS and MK3.

Dual Dayton MK3 and UM15 are pretty much a perfect mirror in the same box/power combo. As per WinISD they should get around 97db @ 10Hz
The dual LMS-R gets to about 100db @ 10Hz

Hopefully by month end we will have a better idea just how good it really is.

Is this statement on the Parts Express site even close to correct?
"• Sealed 3.1 cubic ft. (net internal) with 1 lbs. of Acousta-Stuf polyfill, f3 of 35 Hz with a 0.707 Qtc alignment"
Either I'm using WinSD all wrong or that is some magical polyfill they have there.
Looks like this driver models almost exactly like the 390HF, except with more travel and power handling, giving it the ability to reach about 4db more output across the entire range.
Below each driver was modeled in a 5.0 ft^3 box with enough power to reach xmax at 15 hz.
Have I done something wrong?

Excursion Plot


SPL Plot


Or if space is a concern two Stereo Integrity HT 15's in the same 5.0 ft^3 box with 1200 watts. (yellow plot)

Edited by DavidK442 - 2/2/13 at 3:33am

"Is this statement on the Parts Express site even close to correct?"

i don't believe so.

winisd shows an enclosure around 6.6 cubic feet gives q=0.707.

winisd shows an enclosure around 3.1 cubic feet gives q=0.880.

it would seem like acousta-magic to synthetically double the enclosure size, which is akin to saying almost doubling sensitivity at 20hz in this case.

i think ricci tested stuffed vs. unstuffed in the same sealed cab at data-bass. maybe there is some data there that will help inform their claim.

edit: here is his study: http://www.data-bass.com/data?page=content&id=79

conclusion: stuffing will not double the effective enclosure size. somebody at pe needs to make an edit.

edit 2: oh, and the driver could use more motor. bigger magnets, not more vc layers, but that's not daytons style. :-) good inductance control though. nice xmax. driver looks cool. almost got everything right. ferrari with a prius motor.
Edited by LTD02 - 2/2/13 at 6:35am

I appreciate those folks who posted graphs, but I do not have any idea of how to interpret those graphs, so can someone break this down in how it would compare, in real world performance, versus the HO15 the HF15, or the DVC385? Also, in comparison to the HO18, how low does this new sub go down to, and how is the output versus the HO18?

Marty, you can compare the low freq output yourself with this simple formula:

(x-max in cm x 2) x (Sd in cm) / 1000 = displacement in liters

So for the ultimax 15:
1.9 x 2 x 814.6 / 1000 = 3.09 L


Edit: fixed. It's / 1000 not 100.
Edited by nograveconcern - 2/4/13 at 8:34am

Based on WinSD modeling in a 5 ft^3 enclosure the Dayton UM15 and the RSS460HO would be virtually indistinguishable. The 18 would be marginally louder in the upper bass (50hz - 100hz) but below 50hz the maximum SPL is identical. The UM15 has a smaller driver that travels further (xmax) to give the same output as the 18 inch cone with limited excursion. The HF 15 and UM15 have almost identical frequency response but the UM15 can be driven harder to sound louder IF you have the power. Unless you are really space challenged, have lots of power and a decent equalizer I wouldn't consider the HO 15...though of course this is just my oppinion and I am probably one of the least learned DYI sub guys on this forum.

Though specs and theoretical graphs certainly don't tell the whole story, if you are interested in "rolling your own" learning some of the lingo will make it easier for you to get the results you want.

I am confused, is the end of the formula / 100 like you stated in the first formula or is it / 1000 as you laid out in the example?

It should be 1000 as 1000cm^3 = 1L

Should be noted that the 18" HO xmax is pretty conservative, it has a lot of throw that might not be within the 80% BL curve (or whatever the standard definition of xmax is that parts express follows)

Good to know. I thought the 18" just used the motor assembly for the 15".

even better a 21 !!! yeah Thanx buddy

Would this driver be a better choice for a sealed 3.5 - 4 cubes than say the Fi SSD or Q? If performance isn't vastly in favor of the Fi subs the price difference may sway me towards the Dayton.

Yes.

Has anyone purchased one of these? Is this sub geared towards pure sq or spl? Im thinking about putting one these in my car. For those of you who are proficient in winisd, how big of an enclosure (sealed) will I need if I am sending the sub 500 watts? I'm not sure if car type and music type matters but it will be going into my daily driver, '90 Honda CRX HF, and I listen to mostly trance, with the occasional rock/pop/metal.

500 watts wont be an issue for this driver in any kind of reasonably sized sealed box (under 6 ft3). You could probably get away with a 2 ft3 box for a car audio application... Qtc is 1.0, but the anechoic F3 would still be 38hz, so with cabin gain factored in you will have very good extension. This should be considered a "high SQ" driver, with impressive low frequency output capability. SPL capability is limited by the drivers power handling.

Thanks for the response Jay1. 2 cubed enclosure sounds a lot more friendly. If that's the case I might have 2 enclosures built just to see which I prefer. Since you mentioned 2 cubes, I was thinking about a 2 cubed enclosure with polyfill and a 4 cubed with polyfill. If this was your setup, which would you use?

So you are saying that in a 5ft cubed enclosure the U15 is close or everybit equal to the HO18 below 50hz and above 50hz the HO18 wins by a small-ish margin? If so, then this sub has got to be a heck of a deal! Is that 5ft cubed enclosure sealed or ported? Which do you think, sealed vs ported, would be best for extension and output?

So you are saying that in a 5ft cubed enclosure the U15 is close or everybit equal to the HO18 below 50hz and above 50hz the HO18 wins by a small-ish margin? If so, then this sub has got to be a heck of a deal! Is that 5ft cubed enclosure sealed or ported? Which do you think, sealed vs ported, would be best for extension and output?

If your goal is SQ and deep extension the larger box will make things a lot easier. If you can try both that would be pretty cool. Please report back.

The UM15 can be ported and get a lot of deep bass output, but unless you can handle a massive enclosure, you have to get creative with the venting to make it work. Boxes in the 7-8 ft3 range look good tuned to 16hz, but you'll need the equivalent of a 6" port to avoid chuffing issues, which means a very long port. Here's a guy with a pretty good plan

http://www.avsforum.com/t/1457245/looking-for-diy-sub-advice-volume-2/30#post_22996633

Bringing this back up but with a different twist.

I'm thinking about adding a second sub to my system to be used as a mid sub. The mid sub would be crossed over at 80hz and start to roll off no lower than 35-40hz. My current sub is a 15" CSS XDS in a sealed box tuned to 15hz. The idea would be to have the mid sub give up its duties between 35-40hz to the XDS for the lower frequencies. Not sure if anyone follows Andrew Robinson or not but he just finished an article about this very thing. The idea sounds fascinating enough to try. I'm running a Behringer EP2500 and a FBQ2496. What I like about the Dayton Ultimax according to PE is the power handling, clean fast bass, and the tuning in a sealed box comes close to where a mid sub could work in.

Does anybody have any input on this idea and do you think I'm heading in the right direction with using this driver as a mid sub?

Here is the link to Andrews article in case you missed it.

Thanks in advance for any input.

http://www.andrew-robinson-online.com/take-her-down-using-two-subwoofers-to-achieve-low-frequency-bliss/

it can work.

basspig employs this approach which was documented long before hsu filed for a patent on the idea btw.

http://www.basspig.com/

the problem starts with the low sensitivity of a typical long throw ht driver, is compounded by non-linearities in bl and inductance, and further by the typical resonant frequency (impedance peak) which determines what frequencies the most current is flowing through the coil at. all this adds up to distortion and power compression in the upper bass. many companies are now paying attention to bl and inductance linearity in their designs and sensitivity and power compression can be overcome by using multiples of multiples or even horns.

for a mid-bass module, should you choose to pursue the idea, a um15 is the wrong driver. something like a peavey low rider 18 in a big ported cabinet will be about 10x more efficient in the upper bass than a um15. then based on impedance location, the peavey will pull about 25% as much power at 60hz, so overall, the driver is about 40x more efficient in the upper bass and that can solve a lot of problems.

on the other hand, bass is also about the mains, so they have to be up to the task too...

Thanks LTD for the reply. I'm still wanting to pursue the idea but a large vented cabinet is not in the works. I just don't have the space for it. It took me a long time to find a driver in the XDS15 that would fit into a 4.6cu.ft sealed box that could perform well. Looks like I need to keep doing some research in this area. It is difficult to find much info on it that's for sure. I'm still intrigued by this driver and I do have a second channel sitting there empty.