Subwoofer positioning in bedroom

[Nostromo]

I have read so many conflicting opinions about do's and dont's about optimal subwoofer placement that I am beginning to think that I can't do too badly if I carried it around on my head when I'm home. And yes, I've read the 'subwoofer myths' link and am more confused than ever.

Happily, my options are limited with where I can place the sub of the Sony HT ZF9 soundbar that we are going to install in our master bedroom and so I'll just say what I am planning to do and you guys can tell me off if I am doing something audio-blasphemous.

So, the A-V cabinet is going to be against the wall opposite to head end of our bed, about 12 feet away from our heads. I am having other bespoke furniture built around it (with room for air circulation) but have planned to reserve a specific space for the subwoofer in a nearby corner. The speaker surface will be facing the open room and I'll give at least 8 inches clearance from the sides, top shelf and back wall. The sub will sit on an Auralex Subdude II isolation stand. Will all that be OK for reasonable bass output? Please advise.

 

[shadyJ]

That location is probably as good as any for that sub in that room. Unless it sounds particularly lacking there, it is probably fine, or at least about as good as it can get for a single subwoofer system. By the way, I doubt the auralex subdude will do anything to help that sub.

 

[Nostromo]

The subdude is more for (hopefully) reducing the bass effects to the people immediately below. Other than a year in 1986-7 in a job-allocated Birmingham flat where our kit was limited to a Ferguson Radio-Cassette (still working!) and a second-hand analog TV, this is our first forage into apartment living.

 

[shadyJ]

I don't think the subdude will do much to prevent sound from carrying to your neighbors place, but if you already have it, I doubt it will hurt anything, so might as well use it.

 

[Nostromo]

I don't think the subdude will do much to prevent sound from carrying to your neighbors place, but if you already have it, I doubt it will hurt anything, so might as well use it.

I have not bought it yet. So, is there an alternative that you can suggest that would work better?

 

[Pogre]

Subwoofers and flats don't usually play very well together. Bass frequencies really penetrate through walls and floors.

 

[CajunLB]

I’ve not heard of any way to contain bass frequencies completely, volume control is about the best.

 

[Nostromo]

Subwoofers and flats don't usually play very well together. Bass frequencies really penetrate through walls and floors.

Understood, but I have to do the best I can. How about if I got one of those granite worktop saver or whatever that others have commented in other posts and forums as helpful AND place the subdude on top of that and then the actual sub? Between the two of them, surely they should reduce the through-the-floor subwoofer effects even if they don't eliminate it?

 

[lovinthehd]

Try this http://ethanwiner.com/speaker_isolation.htm

 

[KEW]

Try this http://ethanwiner.com/speaker_isolation.htm

Nice link!

 

[KEW]

Understood, but I have to do the best I can. How about if I got one of those granite worktop saver or whatever that others have commented in other posts and forums as helpful AND place the subdude on top of that and then the actual sub? Between the two of them, surely they should reduce the through-the-floor subwoofer effects even if they don't eliminate it?

Hopefully the soundbar system includes some type of control for Bass or Subwoofer level.
Denon and Marantz have incorporated a feature called LFC (for Low Frequency Containment) which is marketed as solving exactly your problem. Of course it is not the perfect solution that they make it to be but in the end, all it does is turn down the bass. There may be a little of research behind what frequency it takes effect at, but ultimately, it is a relabeled Bass Knob! I suspect Yamaha, Pioneer, Onkyo, etc. have a similar feature, but if you don't have a way to lower the volume of your bass, turning the sub off during "quiet hours" may be your best option.

Just a topical anecdote - In college, I had a friend who lived in an older home converted into apartments. The guy upstairs was blasting their stereo late at night. My friend went up their to ask them to turn it down. I heard them turn it down, but by the time my friend got back they had turned it back up. I let him know and he said that is what he expected, but he saw where the turntable was when he was up there! At first, that didn't make sense to me, but then he pulled the cushions off of the sofa and made a pad on the floor, pulled a bowling ball out of the closet, carefully aimed and threw it granny-style into the ceiling. Wham! - Needle skates across the record and they kept the volume down for at least the rest of that evening!
The ceiling was hardwood. You could see where the ball had hit, but generally had to know to look for it before you would see it.

 

[ryanosaur]

I would add from personal experience... you cannot get away from the effects of low frequency soundwaves by "isolation..." You may be able to reduce the actual physical transference of some of the vibrations or distortions carried by lesser subs transferred throughout the structure. This is a small detail, but not completely without merit.

 

[Nostromo]

OK, thanks everyone. I looked at various links, the points you people posted and ideas from AV guys that I spoke to and decided on this.

1) I'll ask the joiner to place a layer of sorbothane between the laminate floor and wooden 'base' over the area where the subwoofer is supposed to sit. The wooden base will be part of the surrounding shelving but the subwoofer space will have 8" clearance at the back, sides and top and the speaker part will face the room.

2) I'll get a chunky granite chopping board large enough to take the footprint of the subwoofer. Then stick a layer of Polysorb-S Acoustic Foam self adhesive tile on each side of the board. Place this board on the wooden base mentioned above.

3) Place the Subdude II isolation platform on top of the board.

4) The subwoofer on top of the platform.

That would mean there is the subdude, a thick granite board with a layer of acoustic foam on either side, a thick wooden base and a layer of sorbothane between the bottom of the subwoofer and the laminate floor. The room backs on to the en suite and there are no shared walls. Just the floor that I have to worry about.

If that does not work, I'll buy my downstairs neighbour a set of earplugs every fortnight.

 

[lovinthehd]

All this for a bass module with a 6.375" driver (hard to call it a subwoofer) is more overkill than anything, but being a good neighbor

 

[ryanosaur]

Ya... I like the granite... and with some Cork and Rubber appliance vibration pads, I think u cool. in terms of absorbing transmitted physical vibrations, that is.

 

[lovinthehd]

Ya... I like the granite... and with some Cork and Rubber appliance vibration pads, I think u cool. in terms of absorbing transmitted physical vibrations, that is.

What about carpeting/padding underneath it all, too?

 

[ryanosaur]

I agreed: OPs whole description is overkill. His heart is in the right place. A granite slab on spike with some isolation between the Sub and Granite is all he'd need to cut the physical vibrations. Anything else between that and potential distortion will be a function of the soundwaves... and I don't think buying earplugs for the neighbor would help. I'd actually be more p!ssed if my neighbor gave me earplugs cause they listened to loud music. But unless they bought an Orbit Shifter or two... I'd win that battle!

 

[lovinthehd]

I agreed: OPs whole description is overkill. His heart is in the right place. A granite slab on spike with some isolation between the Sub and Granite is all he'd need to cut the physical vibrations. Anything else between that and potential distortion will be a function of the soundwaves... and I don't think buying earplugs for the neighbor would help. I'd actually be more p!ssed if my neighbor gave me earplugs cause they listened to loud music. But unless they bought an Orbit Shifter or two... I'd win that battle!

I was just actually wondering if the bedroom already has that, too. Yeah, earplugs not so much, but that offer of free drinks he mentioned in another thread....

 

[Nostromo]

No carpet in the bedroom or lounge. SWMBO confirmed that it was actually hardwood flooring in the bedroom and some kind of ceramic type tiling (very nice) in the lounge. We are going there today to meet some of the workmen for electrical and plumbing work that we plan to do before we actually move in. I can check, take measurements etc.
Seriously, I don't want to upset any neighbour and so it is OK if it is overkill. Maybe earplugs were not such a good idea. I'll try a bottle of chablis every fortnight; that might work better.