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8x ultimax 18"

5K views 81 replies 26 participants last post by  lknhomeaudio 
#1 ·
Hello guys i'm new here i want to say that i'm sorry because of my bad grammar if there's any ( im not from the us uk or australia ) i'm looking to build a 8x ultimax 18" setup, i dont really know which boxes to get so i'm looking for advice, they are mainly going to be used for home theatre, rap and edm music so in the 19-60hz range. I found some boxes on parts express but they are 4ft sealed are they any good for what i want to use them for? Also space is really not a problem i have a huge room, also any power amp recommendations? I was thinking about just getting one crown xti 6002. Thank you for any and all help in advance. Also i may be willing to go for 16x 18" ultimax's if there really are any benefits but i think it's not worth it with the price spike
 
#35 ·
svs pb 16 ultra's
Those are horrible subwoofers for the money paid IMO, glad you didn't buy any of those... even though you literally rush-dove, head-first, into the depths of the DIY rabbit hole, or should I say northern euro December ice fishing lake? ;)

Hope the wife doesn't break your neck. I don't have a wife because no woman would tolerate 8 hours of continuously loud bass, day after-day after-day, for years/decades. As it continuously gets louder and louder after every paycheck, or while I disappear in the middle of the night for months at a time with no reason given. Level 9000 uncompatible. (and just the way I LIKE IT! ;))

YMMV...
But with 32 18's, that's definitely divorce territory. Hell that's even Lorena Bobbitt/OJ Simpson territory. hehe! :D
 
#6 ·
#8 ·
I feel like you are much better off building 16 VBSS tuned to about 20hz. Your music output will blow the UM18s away, be way way cheaper, and still be amazing for movies. You would be looking at $1600 in drivers for 16 PA460 instead of $2400 in UM18 drivers, and I think one iNuke6000 will power all the VBSS, you will need 4 iNukes for the UM18s.
 
#14 ·
People on here defy logic when it comes to a drivers specs. There are ways to trick dsp amps as well. I would expect 16 vbss pa 460s to hit 10hz very strongly.

It's not uncommon for people to get notes from neighbors on their doors, or texts telling them their house is shaking.
 
#15 ·
Was about to order 16 ultimax-es with boxes, apperantly parts express wants me to pay 4000$ for shipping!?! + import fees which are around 500$ so its like almost as much as the subs ... i hate living in norway lol is there any way to avoid paying for shipping as much for the subs or do i just bite the bullet and check out?
 
#43 ·
As a fellow Norwegian I know it can be frustrating to see the prices in US compared to Norway. I have however bought a lot of HT gear from US: 8xdayton subwoofers with flat packs, 4xcustom spec PAP sub drivers, speaker power amps, Seaton and JTR speakers and some rhythmik subwoofers back in the earlier days of my HT.
To keep the shipping cost down I’ve always used ground shipping in the US to a postal box address in NJ and boat shipping from NJ to Norway. JetCarrier.com have a online portal to arrange these kinds of shipment to Norway.
 
#16 ·
a minidsp 10x10 and 2 fp20k's and 16 UM-18's would be a good start.

You should buy the house next to mine. We would get along just fine... ;)

If you needed another 3db you could get 2 more fp20k's.
Those amps require a 60a 120v breaker or a 30a 240v breaker, each.
You have to order the specific voltage you want. Although it's interchangeable with a few solder points.

That amp would beat the pants off of a xti6k, I know because it even beats the pants off my it8k... so there ya go!

I still think you'd be much better off with 16 of these though: https://www.parts-express.com/bc-21sw152-4-21-neodymium-subwoofer-4-ohm--294-689
 
#17 ·
Welp guess i'm not getting them with sealed boxes from parts express they are 350 each shipping included without the box, guess its expensive to ship mdf xd still havent decided tho, those 21" subs are 2 expensive i could only get 10 of them and they cost a fortune to ship lol. Could you guys help me design box'es for these puppies? I've never built any before so i need like a real step by step guide cuz i aint about to pay 3k$ for shipping cut mdf 😂
 
#22 ·
Download winisd, and put it all the parameters for a few drivers that peak your interest, and play around with different quantities and sizes of boxes and sealed/ported.
http://www.linearteam.org/

There is a very good reason people use the PA-460, it's cheap and it's also 98db/w/m, the UM-18 is 88db/w/m.
3db is a doubling of driver performance.
~10db is about ~10x. It's also 4x cheaper, especially with bulk discount quotes and coupons.
https://www.parts-express.com/dayton-audio-pa460-8-18-pro-woofer--295-036

95% of music is > 30hz
90% of movies is > 30hz

A lot of people think they need more 1-30hz, but what they actually need is more 30-300hz.
 
#24 ·
Excellent Smithers! That's the spirit...

Now, what amp will you use for all these?
There is always the PowerSoft X8 (44kW in 1 RU, with PFC, uni-supply and +90's efficiency)
The 20k still holds good value too.

The good news is that it takes about 32watts to push 32 18's to 1mm but it takes 3200watts to push 1 18 to 32mm, and both are the same SPL.

Of course pushing 32 18's to 32mm is gonna require a nuclear power plant in the back yard. Likely a dedicated 200a service just for the HT room. The rest of the house will require another panel of its own of course.

When they arrive I think this thread is gonna require lots of pics/vids on your part, people will be dying to see the array.
 
#20 ·
Boxes for subs aren't hard to make. Either learn to do it yourself, or subcontract it out to a cabinet maker locally. If you choose to try the first, I'll bet there is a place locally that will cut panels to size for a nominal fee; for me it's ~US30 per full size sheet and they're very accurate.
 
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#40 ·
As you have no speace restrictions, I'd start with 4 UM18-22 in full Marty enclosures (ported). There are plans and cut lists in Imperial, but there should be some in metric as they've been built all over the world.
 
#30 ·
I was going by the following post "The wife is going to kill me 🤣" to mean he'd made the purchase.
 
#33 ·
Well i still havent made the purchase still thinking about it. I know its better to go for the pa subs but i wanted an ultimax from since they came out. Also no its not a troll post i was just saving up for 2x svs pb 16 ultras the ultra towers and the ultra center which add up to about 10k$ and i decided not to get them, so i've got the money ready just cant decide what to get. Also i'm going to call an electrician because i've definently decided to go for 32 subs, 8 against every wall. I have a feeling ill have trouble powering them lol
 
#37 · (Edited)
Have you read all of the detailed measurements charts and commentary for each/all of these subwoofers?
As per here -> https://data-bass.com/systems

You will need anywhere from 2-8 fp20k's to power 32 subs at full excursion, depending on exactly what driver you buy.

The fp20k is basically two 14k's in one box and half the price. There is a fp22k but it is proven to be less reliable in use and in internal guts.

When powering 32 subs, you'll likely need to do some level of series-parallel wiring. Unless you can vastly increase your amplifier budget to power each driver individually.

IMO you are better off with 16 PA-460's for the 40-300hz (ported?), and the rest in RE-18's for 1-40hz(IB?)...

The RE's don't like small boxes (winISD it.)
 
#36 ·
I ordered one um18 and one pa460, i'll see how they sound because i've never heard niether before. They should be here before the 19th of december, and i'll make my final decision than, thanks for all the help, i'll post some pics and give you an update when they arive
 
#38 · (Edited)
If not already, you'll need to download REW and buy a CSL UMIK-1 if you want to do measurements accurately.
http://cross-spectrum.com/measurement/calibrated_umik.html

Sweeps at 95db 2inches and 10ft should do (i.e. nearfield vs farfield.)

To measure at the full SPL, you'll need something like this:
http://spllabusa.com/us/products/bass-meters/usb-bass-meter.html
It's not high res, but it handles uber-high SPL. The UMIK clips at 120-130db, the SPL Lab and Term Lab clip north of 183db...

Pro subs are optimized for >40hz and car subs are optimized for
 
#39 ·
No idea what shipping prices to Norway are for various options. Ignoring that variable...

I understand about the desire to buy the UM22-18. Its a sexy good looking driver.

Speaking practically, if you are looking to buy one or two subs because that's all you have room for, it makes sense to look at top notch drivers because the equation is simple... which gives the most performance at a price I can still stomach. The UM, drivers from SI, BMS, RE, many others are worth considering.

But when you start talking about a dozen or more drivers the equation starts to shift a little. There are now two valid ways of approaching it. One is displacement per dollar. Either you have a fixed budget and are looking to get the most displacement you can for that budget, or you have room for a certain max number of drivers and are trying to get the most value out of that purchase that you can. The other is surface area per dollar, because while the max SPL your system will be capable of is governed by displacement and available amp power, when talking about an array of drivers the real world everyday performance is going to much more closely follow surface area rather than displacement. Things like smoothness of FR across all seating locations, distortion, the mythical tactile impact that accompanies the sound are all more closely related to position and distribution of subs around the room and total surface area available. Cliff notes version... for a single driver in a box there are easily measurable and reasonably audible differences between a PA460, UM22-18, REXXX, and a Pyramid Pro Best Ever Woofer. But for a dozen drivers, other than the rare showoff session that is much much less than 1% of your listening time, there will be vanishingly small audible difference between the PA460 and Ultimax drivers. That's because running either at 1mm for a dozen or two drivers is going to be quite loud. A few mm is going to be as loud as you'd ever play them with the rest for headroom on the rare subsonic notes.

For the first approach, the UM22-18 is actually a pretty darned good value for the money. Better value per liter of displacement than the PA460 and most any other choices. An alternative to check out if you have the space to do an infinite baffle setup is the Ficar audio IB3-18.

For the second approach, the PA460 is a great choice. For any budget of Ultimax drivers, you can just buy twice as many of the PA460 drivers and have same real use output with lowered excursion, lower amp requirements, etc.

Neither approach is wrong. Ultimately everything becomes a budget choice. Your budget seems unlimited to many here, but even you would probably stop short of pulling the trigger on 16+ of the RE XXX drivers. All things considered, 16 Ultimax drivers are going to have more maximum output, plenty enough output at minimal excursion levels to not worry about that difference, and be a little easier to fit and distribution in a room compared to 32 of the PA460 drivers... but for a little more cost (maybe not that much more for you if you save on shipping half as many drivers).
 
#42 ·
Probably.

Here is my ULF Score card, whatever that spreadsheet is supposed to calculate...

https://www.avsforum.com/forum/113-...cers/1488059-your-home-theater-ulf-score.html

To be honest I couldn't even hear my 24 when I powered it on, at this level it added no additional SPL to my room.

Or maybe it did... but I'm just that far gone. hehe! :p

I'd like to add another 4 24's or 6 UM-18's to my room. I have the space, money and amp channels for it...
I figure that is a difference "big enough" that I'd "probably" notice it.
Been pondering and planning that upgrade for 8 years now actually... but definitely more in the last 1-2 years. :)

Besides being able to say >32subs is "cool" too I suppose! :p
29 is so damn close to 32 that it would actually be silly NOT to just keeping going at this point... (Thanks I feel all better now! :))
Inmates running the asylum is how we got this far! It's self-reinforcing. Even crackheads don't like to inject alone etc! :p
 
#44 ·
Whatever you do, dont use partsexpress shipping. Use Jetcarrier. You will save a TON on shipping,especially if you choose shipping by boat, instead of plane.
Partsexpress have free shipping in continetal US, and jetcarrier gives you your own address when you make an account. So you just use that address when ordering from partsexpress.
 
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