maxx, so I would just look at the build of the parts express 113L cabinet and build a bigger one from scratch out of raw 1" plywood which I would love to do, and could do? I will use the UM18-22 driver as you suggest. What do you think my final volume should be?
Bentoronto said: "avoid large flat walls" (not sure what that means. If I build what you suggest, would I be avoiding large flat walls?
Bentoronto said: "avoid large flat walls" (not sure what that means. If I build what you suggest, would I be avoiding large flat walls?
1) You could use this calculator:
Subwoofer Box for 12 inch subwoofer | Ported Box | Pipe
One liter is equal to .0353147 cubic feet, one cubic foot is 28.3168 liters.
2)Bigger can be louder, but a bigger driver in the same size box will generally roll off in the low end more, requiring more EQ.
EQ is a good thing, if you are looking for decent low frequency in your room, regardless of cabinet design or speaker type and size.
Multiple smaller boxes can result in much more even room response than a single big box. They are also a lot easier to build, requiring less bracing. If you are using 1" plywood, dimensions smaller than 2' x 2' would not even need to be braced, but with something large enough for 21", extensive bracing would be needed.
You don't need to "avoid large flat walls", but they require a lot of bracing to keep them from flapping.
Like Carrol Shelby used to say, "there's no replacement for displacement" (or was it "too much power is just enough") but I'd much prefer to use three 12" speakers that equal the displacement of one 21".
Displacement in a subwoofer can be determined by multiplying the driver's bore (Sd) by the stroke (Xmax).
To make a lot of low frequency sound requires moving a lot of air, to move twice as much air (doubling displacement) requires four times (+6dB) the power.
Ported, tapped horn, and horn cabinets can increase output for a given displacement, reducing driver and amplifier requirements, but require more space, which when spreading out the cabinets to achieve even room response, can be an issue.
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It's hard to tell without design it, but i mostly count to guess about 1/5th of the volume as extra for the bracing with this kind of subs, so that is an internal volume of 360L, wich with 1" plywood (25cm for us in Europe) the outside size is about 610x1220x600cm (24"x48"x23.6"). I took sizes that fit a EU standard panel right. This is to give you an id. The actual form of the box is not that important, and even the internal volume is not that critical (read: more or less 300L is good).
About the large flat wall, he means, that if you got large flat walls, you need to brace them to break the resonances and push them out of the passband and low in volume. That means divinding the free surface of the wall in smaller pieces with reinforcements like in the picture attached (not mine, and i don' t know where it came from actually). The space that the brace takes, need to be added to the needed volume of speaker to get the real internal volume needed.
A sealed cabinet also need to be loosly filled with a damping material. This can be a lot, some use long hair natural wool, so use fiber speaker damping stuf (polyfill), some use fiberglass or rockwool isolation...
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I would definitely go with the 21 inch Devastator design.
The mid bass peak will make room interaction and cross over much easier as I have conclusively shown in my ROAR, HROAR and other threads.
The mid bass peak will to some extent compensate the room gain profile in many "normal" indoor listening rooms. Band pass boxes tends to sound very bottom heavy and lacking punch and attack if they are designed for flat FR outdoors.
A long throw, low Bl and high(ish) Qts driver in a bass reflex or closed box will never be able to reproduce music with the emotional impact and effortless organic abundant power of a high Bl, low Qts driver in a high efficiency enclosure (horn, band pass, tapped horn etc). A theoretical flat FR in an anechoic chamber is very far from flat in a normal listening room. I can't understand why a simulated flat response in a purely hypothetical listening space is something to strive for. I have never listened to loudspeakers i a perfect anechoic chamber, and the day that I get te chance I will make sure to bring my cheap MiniDSP2X4HD so that I can EQ the FR of the loudspeakers to my liking in that rather unique environment.
Once you drop the old pre-universal-DSP dogma of "flat FR without DSP" then you will find that there is a lot more available performance to be had from designs like the Devastator (and ROAR/HROAR).
The mid bass peak will make room interaction and cross over much easier as I have conclusively shown in my ROAR, HROAR and other threads.
The mid bass peak will to some extent compensate the room gain profile in many "normal" indoor listening rooms. Band pass boxes tends to sound very bottom heavy and lacking punch and attack if they are designed for flat FR outdoors.
A long throw, low Bl and high(ish) Qts driver in a bass reflex or closed box will never be able to reproduce music with the emotional impact and effortless organic abundant power of a high Bl, low Qts driver in a high efficiency enclosure (horn, band pass, tapped horn etc). A theoretical flat FR in an anechoic chamber is very far from flat in a normal listening room. I can't understand why a simulated flat response in a purely hypothetical listening space is something to strive for. I have never listened to loudspeakers i a perfect anechoic chamber, and the day that I get te chance I will make sure to bring my cheap MiniDSP2X4HD so that I can EQ the FR of the loudspeakers to my liking in that rather unique environment.
Once you drop the old pre-universal-DSP dogma of "flat FR without DSP" then you will find that there is a lot more available performance to be had from designs like the Devastator (and ROAR/HROAR).
After Circloman's post, I am more confused than ever. I thought I had it down to the Dayton UM18-22 in a 300L sealed box then Circloman throws a monkey wrench into the system back with the Devastator. The thing that concerns me with the Devastator is that many of you have said that it's not good at the real low but good at the mid range low. I want the real low. Remember I said I wanted, Remember I said I wanted a sub that would "rattle the windows and a sound you could feel and would also cause the neighbor to come knocking on the door" If I can interpret what some of you are saying, the sealed subs do a good job for quality precise sound, I'm 76 years old and my ears are no longer good at picking up quality precise sound so I'm more into the feel. So, based on this information, maybe the devastator would be the best choce?????
Well, if you see what most use in high end setups, than it's not folded horns, but direct radiator types like sealed. The horns are an old outdated principle of subwoofers from a time they could not make drivers go low or loud enough for their needs. In PA land they now use tapped horns or (in most cases) transflex mainly and in hifi they use sealed with modern drivers like that dayton, or ported enclosures.
This tuba HT is an old design (also seen on their website btw), that was rather good at the time it was launched, but loudspeaker technology moved up fast the last decades and bills designs not... It's not that it can't work, but it's not what you want i think and working arround it's problems is not what you wanted i could see from your initial posts.
C'mon folks, if you have Windows, please provide johnr9q with the HR plot for a bunch of drivers mentioned already. Plots for 300 and 200 litres and infinite baffle are needed (maybe even a BR plot). Less speculation and more HornResp... soon.
My own opinion remains as stated in post #15. A big box filled with stuffing and no back (or large opening) or a labyrinth (which plays organ pedals with spectacular good body feeling in my house to 12 Hz). But if one of those sealed box simulations looks OK down to 32 Hz (just fine for organ and lower is hard to reach without EQ), then that's great.
B.
My own opinion remains as stated in post #15. A big box filled with stuffing and no back (or large opening) or a labyrinth (which plays organ pedals with spectacular good body feeling in my house to 12 Hz). But if one of those sealed box simulations looks OK down to 32 Hz (just fine for organ and lower is hard to reach without EQ), then that's great.
B.
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You seem to be set on the Deviststor so why not just get it? The internet is full of opposing opinions of which thing is best, whether these opinions are correct of based on personal bias is up to you work out.
There are plenty of other options for massive subs, seems like you might be better served by checking out more of the home theatre forums as they do like ridiculous sizes.
Then if you can't work out a cut list for whatever sub enclosure you fancy then maybe stick with a flat pack kit or just buy a ready built one.
There are plenty of other options for massive subs, seems like you might be better served by checking out more of the home theatre forums as they do like ridiculous sizes.
Then if you can't work out a cut list for whatever sub enclosure you fancy then maybe stick with a flat pack kit or just buy a ready built one.
It's not that the Devastator lacks low bass, it just has a lot more upper bass output than most would typically desire in a home situation, and if that upper bass is not "tamed" (reduced with equalization) it will sound "thin" when turned down for music or video use at a conversational level.
The 19 Hz model of the Devastator will put out similar low frequency to a large bass reflex cabinet, but a lot more (+10dB or so) more upper bass given the same power. If you want levels loud enough to make your vision go cross-eyed and feel your chest punched with each kick drum hit, huge horn/BR cabinets with rising upper bass response like the Devastator can do that. You would need a lot more of the smaller subs to achieve the same level.
Rattling windows, sound you can feel, and sound that can cause your neighbor to come knocking on the door all occur at different frequencies and levels. The neighbor bit is very dependent on your and their house construction, distance, and how tolerant or aware of sound they are.
The diagram below can give you an idea of the resonant frequencies of various parts of your body, where you tend to "feel" various tones.
Art
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I told you one possible size, external measures 24"x24"x48" in 1" thick wood should do it, even including a 1" bracing panel (with holes like in the picture above) every 6" to brake the resonance. But a real detailed drawing is a lot of work that not many willl do for free (and i don't have the tools for that to do a cad).
Waxx, after all the looking around and listening to you guys I forgot the dimensions you provided. I am looking for a 21" driver that I could build a sealed box for like the Dayton UM18-22. Which one of these Dayton drivers would be best 21" driver - Parts Express Ships Fast and Ships Free. What would be the approximate dimensions of the enclosure?
None, they are pro audio drivers for horns or ported cabinets. Not fit for sealed. And they don't go lower, they just go louder (wich is not needed in a normal living room).
Surely if you can build the enclosure with your woodworking skills then it will be easy to do the math to work out what size your enclosure will be?
Maybe try the Parts Express specific forum for ideas if that's where you'll be buying it/them from.
Plenty of people are very happy with enclosures that aren't sealed, don't limit yourself.
Maybe try the Parts Express specific forum for ideas if that's where you'll be buying it/them from.
Plenty of people are very happy with enclosures that aren't sealed, don't limit yourself.
bentoronto, your opinions herein (as well as others) give me reason to think highly of your ideas (especially because of your interest in pipe organ sounds). Can you tell me specifically what you suggest, not specifications or technical data but models of Drivers and specific type of enclosures. Others chime in also. (some of you have been specific and I appreciate that) (I really like the 21" size cause I think bigger is better and I want something bigger than my son-in-laws who has an 18")
I hope you all can see how little help the following terms are to someone like me who knows nothing about audio but just wants a pipe organ sound in his house. (actually I have had a couple of pipe organs I installed in my house but that is not practical for me now)
Minimize compression, upper base not tamed, reduced with equalization, tapped horn, resonances, pass band, long throw, low BL, bass reflex, sealed, ported, tapped horn, transmission line, two way tuned port, high efficiency, low tuned, less extension etc
I hope you all can see how little help the following terms are to someone like me who knows nothing about audio but just wants a pipe organ sound in his house. (actually I have had a couple of pipe organs I installed in my house but that is not practical for me now)
Minimize compression, upper base not tamed, reduced with equalization, tapped horn, resonances, pass band, long throw, low BL, bass reflex, sealed, ported, tapped horn, transmission line, two way tuned port, high efficiency, low tuned, less extension etc
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Just buy a ready made one and save everyone the grief.
Wow! A pipe organ in your house, your sub is going to have some act to follow.
Not sure how listing random speaker terms helps. But in for a penny in first s pound so, bandpass, 8th order, dbr, rcf, b&c, close to the edge, massive excursion, size of a house.
Wow! A pipe organ in your house, your sub is going to have some act to follow.
Not sure how listing random speaker terms helps. But in for a penny in first s pound so, bandpass, 8th order, dbr, rcf, b&c, close to the edge, massive excursion, size of a house.
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simple but expensive
Hi John,
Please see attached PDF for my suggestion on the best way to bring church organs into your home...Its very simple, but expensive.
It will give you peace of mind knowing that without any tech knowledge you can simply follow a proven design" recipe" and buy the bits and "plug n play"... results are not in doubt!
DriveRack PA2 | dbx Professional Audio This little beauty is the key that really makes Rods design so easy to set up and use... Bargain of the century!
I have built "ELF" subs Sub-Woofer Controller using
Beyma 15 inch and Precision Devices 18 inch drivers and been totally blown away by the results.... The attached 21 inch PD driver is the ultimate version, if you build it it will rattle the walls and floors never mind the windows!
Cheers
Alex.
Hi John,
Please see attached PDF for my suggestion on the best way to bring church organs into your home...Its very simple, but expensive.
It will give you peace of mind knowing that without any tech knowledge you can simply follow a proven design" recipe" and buy the bits and "plug n play"... results are not in doubt!
DriveRack PA2 | dbx Professional Audio This little beauty is the key that really makes Rods design so easy to set up and use... Bargain of the century!
I have built "ELF" subs Sub-Woofer Controller using
Beyma 15 inch and Precision Devices 18 inch drivers and been totally blown away by the results.... The attached 21 inch PD driver is the ultimate version, if you build it it will rattle the walls and floors never mind the windows!
Cheers
Alex.
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