[Veltinorian]

It has been a long time since my last build (in the signature) and I am planning to upgrade in order to reach the teens with maximum possible transperancy, detail and efortless in the below 25 Hz reproduction.

Initially a thought of building the Tuba HT, but the buil would be complex and at to the end what I would gain is maybe, besides the high spl, more natural sound..but i decided to go ported.

I came across couple of drivers that could really make from the build an upgrade from what what i have now:
Room is not a big problem

Dayton RSS390F-4 (limited in excursion)
TC Sounds LMS-R 15
TC Sounds LMS Ultra
RE Audio XXX 12
RE Audio XXX 15

So I did a WinISD Pro simulation:

I have found out that there are two WinISD files for the RE Audio XXX 12. The one is similar to the pdf specs and the other is Measured by Kyle Keating:

http://www.hometheatershack.com/for...on/14410-downloadable-winisd-pro-files-4.html

And so WinISD suggests different volumes but when i choose the same Volume and Tune Frequency the graphs overlap completely.

The LMS-R 15 cant really go that low compared to the XXXs and I think am going to exclude it from the equation.

Win ISD suggests fo RE Audio XXX 15 392 Liters (13 cubic feet) Ftune is 15 Hz which results in F3=13,2 Hz. For XXX 12 Kyle Keating version i get F3=15,2Hz in 125 Liters. The other file yeilds F3=16,5 Hz in just 95 Liters. So this comparison leaves me thinking right now that the XXX 12 is a good candidate. In such case I would be 10 Hz below what i have right now (http://www.hometheatershack.com/for...projects/47399-nice-black-satin-finish-9.html).

LMS Ultra doesnt simulate very well/ I couldnt achieve nice graph thats why i excluded it. I suspect it is the best sub out there but the price makes me think twice. And being from Europe, Germany makesm the delivery costs high.
There is another driver CSS SDX12 but i think the RE Audios and TC Sound are superior.

What do you guys think, which way would you go?

 

[Mike P.]

You should show what the SPL graph is. Have you kept the cone excursion in check with the appropriate hi-pass filters in your modeling?

 

[Veltinorian]

Thank you Mike :wave:. I included the SPL levels, and the excursions with the HPFiltering. With 1000W seems everything in control.

TC Sounds beat the XXXs in this department, but XXX reach lower what is more appealing for me



Also there is a problem with the port air velocity, i need to increase the port diameter.. What is an acceptable air velocity?
Or i need a very flared port.

 

[Mike P.]

Is your air port velocity set as M/S peak?

 

[Veltinorian]

Yes should I changed it to simething else?

I have changed it to rms:

 

[Mike P.]

Can you upload the Project File for the XXX? I'll have a look at it when I get back from a hockey game.

 

[Veltinorian]

Thank you dear Mike, appraciate it man

here are the files, the second one os done with the T/S Parameters measured by Kyle Keating. The file i downloaded from the database here at hts as well.

 

[Mike P.]

Concentrating on the XXX15, the port air speed will be affected by how much power the sub will get. It is capable of handling a 1800 watts, would you give it this much power?

 

[Veltinorian]

To be honest i dont think i will use more that 200W, but what i want to use every now and then, to show off :bigsmile: i will use up to 1000W, intend to use iNuke 3000 DSP model, but very rarely though. I directed my attention to those drivers because of the possible low distortion, higher detail and transparency. When it comes to high SPL i will always have the option to turn the knob up.


P.S.Mike, if there is another sub that i am not aware of that comes close to the LMSs and the XXXs let me please know (especially when it comes to sound reproduction below 20Hz with the lowest distortion around 110dB)

 

[Mike P.]

The Mach 5 Audio UXL-18 would be a contender.

 

[Veltinorian]

I remeber those speakers, i checked the T/Sparameters, it has low fs of 18.6., Qts is low though which would reuire larger cab volume, what is your opinion between maybe XXX 15 and UXL18?

 

[Mike P.]

Both the XX15 and the UXL-18 model the same. 13 cu.ft. tuned to 15 hz, 1000 watts input, a 10 hz hi-pass filter and a 8" round port 40" long. My choice would be the UXL-18 since it is designed specifically for home theater.

 

[Veltinorian]

The UXL seems pricy with 530usd or 530 canadian dollar which is 477usd. Nonethe less i have found on ebay is the XXX 15 549usd, which is very similar. The xxx 15 with.its 54mm xmax is the more capable driver, heavier motor.

The question is which one of the both, the xxx15 with F3 13.6Hz in 13 cu.ft. and xxx12 with F3 15.6Hz in 4 cu.ft. It seems to me that it.isnt worth the.extra 2.Hz..maybe in room i.would get practically the same output in terms of low extension, so xxx 12 seems for.me to be the favourite.

Edit: aproppo the UXL is a 94dB/ 2.83V driver ..what so efficient? Bl is very strong as.well 22.33..

 

[Mike P.]

If you are comfortable buying a used driver from eBay then go for it. It's is an awesome driver.

 

[Veltinorian]

It is new i have been looking to those XXXs for some time now. It is remarkable how those subs dropped in price.

Are there other subs form the car audio scene that can make the live of the XXXs difficult? I habe seen some Digital Design, Fi etc., but they are 30Hz+ Fs drivers, hence not suitable for ht.

 

[Mike P.]

As far as Xmax and power handling go it would be pretty hard to beat a XXX.

 

[Veltinorian]

I have applied the corresponding maximum power to each driver and played with the filters so that Xmax is in check for every one of them. Also included the LMS Ultra, for which i have applied also a LPF at 70Hz to take care of the hump:

As expected LMS Utra comes on top, followed by XXX 15 and UXL-18.
Low extension wise XXX 12 and UXL-18 are pretty identical. LMS Ultra doesnt position itself that low. And the lowest sub is the XXX15 with F3 13.5 Hz. LMS Ultra has F3 15.4Hz.

The XXX 12 in 4.8 cu ft. will produce 114 dB at 18Hz and will have 111dB at F3 15.2Hz..:hsd: For me guys those results are outstanding, can i trust those that in reality i will get something very simular? This low extension is unbelievable for a 12 inch driver. As a 21Hz Fs speaker (or even 22Hz as measured by Kyle Keating) is it reasonable to tune the box at 17Hz? And on top of that room gain, what could I gain realistically (my room is 430 sq. ft)?

 

[Mike P.]

The problem with the XXX12 is porting, maximum port air speed should be 26 m/s and the first port resonance needs to be higher thn 125 hz for home theater.

 

[Veltinorian]

Thank you for helping me Mike.
Those are requirements that are necessary but also seem hard to accomplish. I am thinking of using passive radiators (alike my previous build). I am considering of 2x TC Sounds VMP 15 or 1x VMP 18. Do you have also something in mind as alternative?

Just curious, in case i use.ports, about the first port resonance, where can i.see it.in winisd and how is it to tackle?

 

[Mike P.]

You'll have to try modelling different PR's and see if they can handle the XX12. The first port resonance is under the Vents tab in WinISD, the longer the port the lower the FPR goes.