# Placing downwards-firing sub into cabinet



## pret (Mar 5, 2015)

Greetings to all
I'm new to home theater topic, albeit have a very general acoustics understanding (due to engineering background).
I'm doing a renovation in our condo, there will be entertainment cabinets in "float" design on the wall underneath the TV, the cabinet will be raised above the floor by ~8" fixed to the wall. Due to decor constrains and also due to having pets I've chosen downwards firing sub of DALI E-9F that will have to be enclosed inside the rightmost cabinet that is approx 8-10" from the room side wall.
I'll be doing a failry large hole in the cabinet bottom to allow the sub port to fire onto the floor, however not sure what to do with the driver (9" driver). There are two options:
1. Leave the entire unit inside with the appropriate hole at the bottom for the port (so that the driver will work against cabinet inside wall
2. Cut a large opening at the side of the cabinet wall and position the unit so that the driver would work against that opening allowing approx. 10" to the room side wall

In both cases there will be the appropriate opening at the bottom of the cabinet for the port of course.

So that question is whether is is necessary to allow the driver to breathe outside or it is not necessary, the port opening is enough ?

What do you think ?


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## theJman (Mar 3, 2012)

I vote for option 3: none of the above. 

Placing a subwoofer in an enclosure is never advisable, for several reasons. It's virtually impossible to eliminate cabinet resonance, meaning something will ultimately rattle. The restrictions in space will often lead to a compromise in sound quality and quantity as well. Lastly, the amp is cooled strictly by convection. Limit the air movement and you're likely to have problems, ranging from thermal shutdowns, compromised longevity or even fire hazard in extreme cases.

All-in-all, a subwoofer needs to 'breath'. For many reasons.


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## tonyvdb (Sep 5, 2007)

Fully agree ^^
It is not advisable to put a sub inside something else. Vibration, heat and sound quality issues will result in doing so.


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## pret (Mar 5, 2015)

Obviously, no question, leaving it alone on the floor would be the best option, would I have that option available no questions would be asked 
However, given the restrictions forcing to have the sub enclosed as described, so far it appears option 2 is more appealing, also allowing better convection cooling then with a single opening at the bottom. Am I wrong ?
The question that I still cannot comprehend, technically speaking...for proper operation (bearing in mind downwards firing) is it mandatory to have the driver to face open space rather being enclosed ?


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## tonyvdb (Sep 5, 2007)

do you have an option to place it behind your sofa or other seating, maybe a plant can hide it?


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## pret (Mar 5, 2015)

Unfortunately not really, nothing that would allow to blend it into the decor in seating area.
Besides, we have pets (two cats) of my wife and kids, these creatures (pets I mean) may be curious enough to give hard life to the sub at nights would it be sitting on the floor...I can imagine the fur getting into the port wouldn't it be downwards firing type, tearing the driver membrane...


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## robbo266317 (Sep 22, 2008)

Since it is driven by a class D amp you may get away with option 2.


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## pret (Mar 5, 2015)

Thanks a lot
Why class D amplifiers allows a headroom for option 2 better then other amplifier types ?


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## willis7469 (Jan 31, 2014)

Agree with Tony and Jman. I think it would also suffer from some strange type of cabinet gain making it boomy and muddy. If there really is zero chance of leaving it out, I might look at a real in wall sub. Maybe a diy sealed section integrated into the cabinet?


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## pret (Mar 5, 2015)

Well, the particular sub has been purchased already and I think would compliment the rest of the setup nicely once appropriate solution could be figured. We he a carpenter doing for us the furniture, Perhaps there is some way to ask some particular reinforcements in cabinet section that will hosts the sub ?
I'd also would consider some kind of absorbers to stuff that section inside the cabinet to try to diminish the coupling. Any ideas about that ?


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## Chromejob (Feb 19, 2015)

Having just read up on bass management and sub placement (including Subwoofer Crawl how-tos), I'd say that if you can only put the sub in an airborne cabinet, then get mains that can handle low freqs and eliminate the sub. Until you can get a model that you can actually place where it will perform best. Maybe get a model like the SVS SB-2000 or better with a fixed grill that the creatures, er pets, can't mess with.

The recipe you've sold yourself on sounds like a guaranteed failure or case of buyer's remorse. 

Just my 2¢. 


// Posted from Tapatalk 3.2.1 for iOS - later versions are //


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## pret (Mar 5, 2015)

Thanks a lot guys, appreciate your honest opinion.
I'm going to try to get approval from my wife to relocate the sub somewhere on the floor perhaps in the corner area behind the sofa or something in that direction. Need to consider some kind of enclose for the sub to protect from the pets when not in use (it has not grill protecting the driver)


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## robbo266317 (Sep 22, 2008)

The class D amps don't generate as much heat as other types of amps so that is one issue that you don't need to consider as much when finding a location for it.


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## Lumen (May 17, 2014)

pret said:


> Thanks a lot guys, appreciate your honest opinion.
> I'm going to try to get approval from my wife to relocate the sub somewhere on the floor perhaps in the corner area behind the sofa or something in that direction. Need to consider some kind of enclose for the sub to protect from the pets when not in use (it has not grill protecting the driver)


I use decorative, iron fireplace grates to keep my dogs away from speakers and bass traps. They're curved and heavy, so they don't topple easily. I suppose a cat might knock one over with a running start, but I'd be more worried they'd leap over one. Just some food for thought onder:


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## robbo266317 (Sep 22, 2008)

So, what are your plans now?


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## pret (Mar 5, 2015)

Well guys, all of you sounded so convincing that I changed my mind and will be locating it on the floor where it belongs to, in the oppopposite room corner to the entertainment wall with th TV and fronts, more or less behind the sofa. Or along the wall. Just need to figure some decorative solution to protect it from pets when not in use.
Recently got the respince from DALI customer support, they also where quite clear of avoiding my idea at all costs...also elaborating that excessive distance to the floor for down-firing subs is bad idea resulting in weak and muddy bass, while woofer opening would certainly be neccesary...still csbinet rattling, resonances will most certainly unavoidable

I"m onsidering now wiring the RCA cable inside the wall towards the intended corner and installing there in-wall RCA outlet for sub

So


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