The GRS looks like a capable woofer, what does it cost. You will need 3 of them to match one Dayton UM15.
To your first point….dual opposed subs in one enclosure serve one purpose by design….to stabilize the enclosure with the moving mass of each driver countering the other…..that’s it. You wind up with one very large and heavy enclosure and has limited placement options and requires EXTENSIVE bracing to keep the longer cabinet panels from resonating, increasing the complexity of the build and weight.
Now let’s look at the two drivers firing opposed in a linear direction from a fixed point in space……the absolute BEST way to produce really massive waves with greater amplitude where low ( or long )frequencies are concerned. Wave propagation is the same regardless of the medium….water, light, sound, etc……..the boundaries make the difference and given typical home construction and the freq we’re concerned with here, irrelevant. Even if you were to build two separate enclosures which would offer placement flexibility, you still wind up with greater peaks and deeper nulls than if you had one driver/box and the flexibility to place it where results were optimal in your space.
Now 3-4 individual boxes and the performance gains and smooth in room response become evident…..you have an exponential increase in wavefront combination and smoothing……large rolling waves simply can’t exist in a closed space as they’re continuously bombarded with opposing waves from multiple directions. You could also look at overall sound quality and control advantage with 3-4 motors and the flexibility of 3-4 smaller boxes to place optimally.
I’m not suggesting you build 3-4 subs…..but what I am suggesting is that one sub is going to be better than 2 in a closed space and two subs in one big box is the worst of the three options……..
If you have such a build, it is quite easy to shut one woofer down and compare. I'm pretty sure he will prefer the two woofer setting. The reproduced frequency is too low to have such a negative effect as long as the distance of the cones is lower than half a wavelength.
1/2 a wave at 100Hz is about 1.7m. So no problem here.
By the way, if you listen to stereo from two boxes giving a mono signal, as usual in the low end, what happens there?
1/2 a wave at 100Hz is about 1.7m. So no problem here.
By the way, if you listen to stereo from two boxes giving a mono signal, as usual in the low end, what happens there?
Unfortunately, I’m from canada. And it’s 125$ USD to ship to my place.
If I take 3 or 4 12” 180-240usd
+ 125 shipping
305 to 365$ usd.
30% conversion rate.
405-475$
15% sales in Quebec/custom/duty.
465-546.
I get 2 mx15, from a shop in Quebec, for 610.
I don’t get to save a lot going 12in drivers.
You need 6x to replace 2 UM15-22
On the other hand, for you in the US, two for 60$ would make a very capable sub, using up less space.
On the other hand, for you in the US, two for 60$ would make a very capable sub, using up less space.
yeah, but I’m not in the us! Hahah.
What you think of the Dayton mx15?
I’m about to pull the trigger on those.
Octave math:
Fh = Fl*2^n
Fl = Fh/2^n
n = ln(Fh/Fl)/ln(2)
where:
Fh = upper frequency
Fl = lower frequency
n = octave spread
FWIW I came up with a ~141.58 L net Vb/dual series 15UM-22, so a calc'd ~0.96 Qtc (1.0 Qtc HR) based on published specs with max power limited to ~430 W/115 dB_m/25 Hz/2 pi.
Id say so. Why?
I’d have to re-read all the post to see where I got lost.
But I’ rather respect my budget and space available.
My fiancée really want leg under the table like the legs I did for the kitchen island, so I get a 16” height box. Um18 doesn’t fit there anymore.
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Ideally need a lot of dynamic headroom down to <20 Hz built in for 'chest thump' since your room doesn't appear to have much LF gain.
Just build that 155 liter 2x15" monster. You will blow the glass out of your windows with it and rattle any object not securely screwed down. Your room will add a ton low frequency gain. Your current baby sub is just not able to activate these frequency at all, as it has a low cut to protect it.
This size sub, even with one 15" chassis, in such a small room, is considered ridiculously over sized by any serious person. Which is exactly what a HT fanatic wants.
The Behringer iNuke6000DSP amp you will use is able to drive the cones to any excursion they can do and even further. Find any commercial sub that fit's these specification and does not have cost cut's of some kind. I know of no commercial HT sub that is powered by 2x 2200 Wrms / 2x 3000W peak (Behringer Data from 2011) or even half of that.
The only "downside" compared with extreme expensive, giant subs, may be with the DSP. It does not work by it self in auto mode, but has to be adjusted by you, with the help of real in room measurements. IMO this is an advantage, as any auto function can fail, if you have a somehow special room. It may work in most cases, but not all. On the other side, your manual adjustments will get the best out of any room there is, tailored to your ears and butt.
That beside from Audessey maybe making some final touches. Audessey XT32 in fact is a very capable system, even with unconventional rooms. As mentioned it has, as any automatic function, sometimes limits.
This size sub, even with one 15" chassis, in such a small room, is considered ridiculously over sized by any serious person. Which is exactly what a HT fanatic wants.
The Behringer iNuke6000DSP amp you will use is able to drive the cones to any excursion they can do and even further. Find any commercial sub that fit's these specification and does not have cost cut's of some kind. I know of no commercial HT sub that is powered by 2x 2200 Wrms / 2x 3000W peak (Behringer Data from 2011) or even half of that.
The only "downside" compared with extreme expensive, giant subs, may be with the DSP. It does not work by it self in auto mode, but has to be adjusted by you, with the help of real in room measurements. IMO this is an advantage, as any auto function can fail, if you have a somehow special room. It may work in most cases, but not all. On the other side, your manual adjustments will get the best out of any room there is, tailored to your ears and butt.
That beside from Audessey maybe making some final touches. Audessey XT32 in fact is a very capable system, even with unconventional rooms. As mentioned it has, as any automatic function, sometimes limits.