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Discussion Starter #1
I am a new home theater user/owner. Have bought a new house and am trying to figure out what to do w/ the subwoofer.


If I put a subwoofer in a cabinet in the TV room would I get the desired effect or will it be muffled?


What if the cabinet door was open or the cabinet door was mesh?


I know the subwoofer is non-directional, but I am trying to figure out how non-directional.


Do I need to have it on the floor and relatively unobstructed?


Sorry if this is a neophyte question.
 

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We have installed quite a few subs this way. We only do it if there is no other place for it that makes any sense. You have to be concerned about rattles and buzzing, etc. The cabinet should be internally braced and free of rattles. We have sometimes vented the woofer thru a hole cut and covered with a decorative grill of some type. Also, depending on the construction of the cabinet, you may be able to cut vent holes downward into the cabinet if it overhangs a jutted base unit. The sub should be mounted so that it cannot move within the built in. You might also want to consider in wall sub(s) or in ceiling. This would free up the cabinet to be used for something else.
 

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As Mr. Hookup confirmed above, you can most certainly enclose a subwoofer in an entertainment center.


There are obviously some issues to consider. There needs to be a sufficient means of airflow from the woofer/port/PR surfaces to the room, and you don't want the cabinet rattling apart. There are many different options depending on what your flexibilities are. Are you building the enterainment center? Working with a cabinetmaker? buying a pre-fab unit like Jay Rambo? Each case offers different avenues. There are many subwoofers which work well in such situations, NHT and Triad are two particulars I would check out from retailers, and there is also Adire Audio . Adire has their Rava subwoofer for $399, along with even more robust options, and if you really are willing to customize, would assist you in building a custom subwoofer into the cabinet. In fact, for some of my own projects (I still do freelance work) I've been talking to them about offering semi-finished custom subs for In floor and in-cabinet options.


That's another option as well, do you have a crawl space under the room in question?
 

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I tried this with my entertainment center, and it worked fine, until I put stuff in the cabinet. It was the stuff that rattled. I am telling you this so you don't make the same mistake I did. Test it with everything in it's place, not just the A/V equipment.
 

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I just want to lift mine off the floor. I have a horrible image of my cleaning lady slapping a wet mop around it. I'm not very handy at building things. Can anyone make any recommendations?
 

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Quote:
Originally posted by where1
I tried this with my entertainment center, and it worked fine, until I put stuff in the cabinet. It was the stuff that rattled. I am telling you this so you don't make the same mistake I did. Test it with everything in it's place, not just the A/V equipment.
This is why we often will construct or modify a cabinet to have an open bottom where the sub will be placed so it is not mechanically coupled to the cabinet. This way the only rattle inducing forces will be from acoustic power, not mechanical vibrations. Finding a subwoofer with opposing drivers like some from Mirage, Martin Logan, and our own ContraBass also solves this problem as the cabinet then does not rock, dance or shake. Of course the cabinet must be rather large to accomidate the space to build in a ContraBass. :rolleyes:
 

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Discussion Starter #7
thanks all for the input.


guess I should have put some more info. The entertainment center is built into the wall of the house. The cabinets are part of the entertainment center. I doubt it would shake. However, I can see other stuff in the cainets being effected. Interesting.


The house does not have a crawlspace. It is on a concrete slab. Wood floors. The unfortunate thing is that the wall w/ the entertainment center is not contiguous w/ the rest of the walls in the room, so if I ran wires, it would have to be up in the ceiling, then down the interior of the side walls.


Is a ceiling mounted or "in ceiling" subwoofer an option?
 

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Mr. Hookup and Mr. Seaton:


Sunfire makes a couple of Architectural subwoofers which they claim are made specifically for cabinet applications.


Here's a link to the True Architectural Subwoofer .


I would be interested to know if you have had any experience with these subs and if you have any opinions on this line of subwoofers. Do you believe that this design is superior to standard front-firing subwoofers? I'm assuming that downward firing subwoofers would generally be unsuitable for cabinet installations unless it were sitting on the floor through a hole cut in the cabinet.


Thanks.


Larry
 

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I have built a subwoofer in to an endtable in my living room. The endtable is a "Sauder" brand of build-it-yourself furniture at Walmart. It is a 12" with about 150watts (plays well with other speakers down to 25Hz). To keep down on vibrations, Phone books were relocated to the drawer in this endtable, other stuff was moved to the other endtable (no subwoofer in this one, yet).


The result is that I have a sub, that is much better looking (and sounding) than that big black Klipsch that was in the corner.
 

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Hi Larry,


I had stumbled across this microsub at the CEDIA Expo this year. At first I thought Bob was making a computer sub. :rolleyes: This is basically the 10" driver as used in a few other of his microsubs, but in this case sealed. The driver is front firing. It weighs an immense amount for it's size between the motor and the amplifier required to get any significant output from that small of an enclosure. I would imagine that using a pair in a room could work to decent effect and be able to reach more useable levels. I was at least impressed that the marketing didn't get tooo far ahead of the subs capabilities. Physics dictates that the sub is only going to produce its claimed 107dB (notice no distance or condition qualifies this number) down to about 30Hz at best when against a wall as cabinet mounting would imply, and at best down to the mid 20s. Not too bad for a tiny box, yet I do not know how much it costs.


This is not a down firing design, but rather just a single, sealed, front firing driver. While certain considerations need to be made, down firing designs can be used, yet the amount of air space around the bottom of the woofer and the exit area need to be considered. If you shoehorn a down firing design into an enclosure the exact same width as the sub itself you now have now loaded the woofer by closing off the other 3 sides of the box. You could likely raise the woofer up higher to maintain this amount of air space, or build the opening wide enough to allow similar air flow. Loading a down firing woofer will change the bottom end response, and can affect port tuning if one is used. Front and single side exit subs do make building in a more straightforeward process. For this reason we are creating application notes for our own subwoofers for just this situation. For example, in the case of the ContraBass , 4-5" are needed on each side with a woofer and PR of the subwoofer to not affect it's low end response.
 

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Quote:
Originally posted by hastalavista
It is a 12" with about 150watts (plays well with other speakers down to 25Hz). To keep down on vibrations, Phone books were relocated to the drawer in this endtable, other stuff was moved to the other endtable (no subwoofer in this one, yet).
This is precisely why I strongly recommend only using opposing driver configurations in anything used for furniture or anything which will be coupled to other items. I actually preffer this configuration for all subwoofers, as then the box is relieved of having to weight down the subwoofer to keep it in place, and only has to be rigid to do it's duty. Martin Logan has a very appropriate term they use for such a configuration... Balanced Force Configuration.
 

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Mark:


Thanks very much for your response.

Quote:
Originally posted by Mark Seaton
... Not too bad for a tiny box, yet I do not know how much it costs.
The Sunfire True Archictectural subs list for $1,395 in black and $1,450 in white.


Carver Corporation also makes the Knight Shadow which is nearly identical except the amplifier is smaller. I have one of these "poor man's sunfire architectural" subwoofers inside a cabinet and there's room for a second stacked on top of it. It lists for $800. I found that it hopped around inside the cabinet until I isolated it with the rubber feet provided. I use it almost entirely for movies. I have a second very average subwoofer in the back of the room dedicated to the surround channels and my old Polk SDAs also put out a bit of bass. I also have a pair of Buttkicker tactile transducers. Altogether as a whole I'm pleased with the arrangement, but someday I may stack that second subwoofer.


Thanks again.


Larry
 

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Would there be any problem with me placing my subwoofer on a cinder block (covered with fabric of course) to get it off the floor?
 

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PJ,


There's no reason you can't place your sub on a cinder block or other platform to raise the sub up off the floor. If this happens to be a hardwood or stone floor, you would probably be best served to place 4 or more small, hard rubber feet (look like stoppers) between the "platform" and the floor. There are many viable mean to prop up your subwoofer. You might want to find a local installer to help you out with something simple, but don't get caught up with fancy and quite expensive cones and other "isolation devices." A piece of cut stone or wood with some sort of feet below it can work great, and can even be made to thread into the threading of the factory feet.
 

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Larry: I have nothing derogatory to say about the Sunfire Sub, but I think that you should keep certain things in mind if you are to engineer one into a built in or cabinet. Despite the obvious advantage that you alude to (its small size), there are a few obstacles to overcome in such an installation. Bear in mind that the Sunfire incorporates, among other things, a huge amplifier of 2700 watts (although it is not, nor is it necessary to be a full range amplifier). That is how they are able to keep the amps' size down to a minimum. You are also dealing with approximately a 9" active cone along with a passive drone of equivalent size. The difference between this driver configuration and others is in the cone travel. Whereas a normal sub has a cone motion of less then 1", the Sunfire design has a cone motion of over 2.5"!!! It actually has a bore & stroke akin to that of a car engine! That is how the Sunfire is capable of moving more air then a 15" woofer. You must take this in to consideration when putting this miniature behemouth into any cabinet. Due to the large amount of air movement that it creates, you will immediately notice such things as rattles, vibrations, things moving around that are not bolted or glued down. Saying that this sub is made to go into a cabinet or built in with no problems is like saying its OK to put a jet engine on the back of your car for some added horsepower.
 

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Quote:
Originally posted by Mr. Hookup
...Due to the large amount of air movement that it creates, you will immediately notice such things as rattles, vibrations, things moving around that are not bolted or glued down. Saying that this sub is made to go into a cabinet or built in with no problems is like saying its OK to put a jet engine on the back of your car for some added horsepower...
I was wondering why the movie Air Force One sounded so realistic!!! :eek:


Seriously, I do appreciate the advice of a person such as yourself who deals with this everyday.


When I first placed the Carver Knight Shadow in a cabinet, I kept finding it located in different positions. At first I thought it was me moving it to make adjustments on the rear control panel, but then I realized that it was hopping around in the cabinet!! I guess I didn't immediately notice it because everthing in the room was rattling, even me, :D with tactile transducers being powered by a 2,000 watt amplifier.


Larry
 
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