A bit of a thought experiment at the moment with not much else to do...
I'd like a sub, but live in an apartment and don't want to annoy the neighbours
I thought I could have near field subs, probably behind the head cushions on the sofa, or with a slot exit behind the sofa near head height
The mains are approx 4 meters away, so if the subs are 0.5m away from my head, they could be approx 18dB quieter
If they were too close, any head movement would change the sound level too much, and too far away would need too much output for the neighbours, so there's going to be compromise. Also, they wouldn't add much if walking around the room, but since I'm mainly thinking about movies, this wouldn't be an issue
The mains are flat to about 50Hz and another octave would be nice
Any thoughts please? Thanks
Brian
I'd like a sub, but live in an apartment and don't want to annoy the neighbours
I thought I could have near field subs, probably behind the head cushions on the sofa, or with a slot exit behind the sofa near head height
The mains are approx 4 meters away, so if the subs are 0.5m away from my head, they could be approx 18dB quieter
If they were too close, any head movement would change the sound level too much, and too far away would need too much output for the neighbours, so there's going to be compromise. Also, they wouldn't add much if walking around the room, but since I'm mainly thinking about movies, this wouldn't be an issue
The mains are flat to about 50Hz and another octave would be nice
Any thoughts please? Thanks
Brian
Brian,
Should work fine, though you may want to delay the mains by around 10-12 milliseconds to time align them to the subs.
That said, what you hear first will be perceived as sounding louder, so you may actually prefer no delay if you like lots of low end.
Art
Brian,
I live in my own house (in fact, my house is the only house on the block), so I don't have to worry about neighbors. I have 3 subs in the room and two of them are within 1m of my couch. I find the near-field subs are better at subjugating the rooms influence on bass response. (make no mistake - the room is still in control of <150Hz - but with the subs close by they have more influence than they would otherwise)
Art is correct about delay. But I will warn you that with a multi-sub system, where each of the subs is at a different distance to the listener, the delays are hard to get right. The good news is that I don't seem to notice much difference. My perceived difference in listening to what measures better of worse is pretty minimal. That kind of surprised me.
I live in my own house (in fact, my house is the only house on the block), so I don't have to worry about neighbors. I have 3 subs in the room and two of them are within 1m of my couch. I find the near-field subs are better at subjugating the rooms influence on bass response. (make no mistake - the room is still in control of <150Hz - but with the subs close by they have more influence than they would otherwise)
Art is correct about delay. But I will warn you that with a multi-sub system, where each of the subs is at a different distance to the listener, the delays are hard to get right. The good news is that I don't seem to notice much difference. My perceived difference in listening to what measures better of worse is pretty minimal. That kind of surprised me.
I use three subs in a room around the back seating area, they are time aligned and EQ’d to combine in a even response across the seating area and over the sub frequencies, you then just need to ensure the sub roll off and front speaker roll on are in phase and level match. Having removed my processor and moving back to analogue out in a cinema room you can align up to 4 subs and EQ using a mini dsp HD
I have managed to get within 3-4 db over 17-60 Hz over a 2m searing area, this would obviously not be possible with only 1 sub
I have managed to get within 3-4 db over 17-60 Hz over a 2m searing area, this would obviously not be possible with only 1 sub
In my experience it is exactly as Brian says. Never did I have better bass than with the Audio Concepts Titan diy subs 30 years a ago when listening nearfield with one sub at each side of the couch. The sense of envelopment and thightness of bass (with just a handfull of watts) was just astonishing. These subs were impossible to set up and blend with mains in the far field. As it happened, in Speaker Builder magazine thereviewer of the AC subs, Garry Galo, also ended up with a nearfield setup after much experimenting.
Art, You have the delay backwards... the sub is near the listeners, so its sound will arrive first. Therefore you need to delay the SUB by the distance of the mains divided by the speed of sound (roughly).
If the HP and LP filters used on the subs and mains result in a 180 degree phase shift AND the distance between the two happens to correspond to multiples of the acoustic crossover wavelength, a polarity inversion may result in an "in phase" output at the listening position, although may not be "time aligned".
Thanks for the replies, I had initially thought of something like this, just a simple sealed box on some kind of compliant base (I'll probably drink the beer first). I would be using DSP, so delay is no problem to match the main speakers
How would I do a dipole sub here?
I hadn't thought of a butt shaker, would the sound/vibrations go through the floor to the neighbours?
Brian
How would I do a dipole sub here?
I hadn't thought of a butt shaker, would the sound/vibrations go through the floor to the neighbours?
Brian
It would be interesting to see/hear what happens. An H-frame along the wall, technically your seat is in the null but the sound is going to be reflected around the room numerous times before your brain even registers it.
It doesn't have to. What you would do is securely attach it to he frame of your chair, centrally if possible..I added a small piece of wood to my 3 person couch as I had no central beam under the center butt - not sure if it mattered, but I'm sure it spread the effect better across the couch. I sit to one side. If you find the sound propagating through to the floor for some reason, you can add some rubber under the feet or something, but with a carpet and pad, it'll be ok as is I'd think. I have a cement floor, so I cant speak from experience.
It gives you like 80% of the effect of a LFE, especially below 40hz, without the noise propagation. At night, I run just the buttshaker and little to no subs if I don't want to wake the wife. So cool. I actually run mine 5-80hz, and just strong enough that I can feel it during explosions and dinosaurs walking, but low enough that's it not vibrating the chair parts all the time or during male dialog (although when I first got it, for a couple weeks, I cranked that sucker!). The first time you feel it playing loud, it'll make you jump!
Its amazing how strong they are. I run mine at -20db from the rest of my subs, but I am using too big of an amp for it (200w). I have a second one on a lazyboy chair and run them both to present the amp with a 8ohm load (they are 4 ohm natively). Give it a try, you'll love it!
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I’ve been thinking of where to hide a subwoofer in my living room, and was thinking about building one to either go under the couch, or simply build one in the shape of a couch, add cushions and some upholstery... voila! it would make it a lot easier to build a big box if that’s what the driver needs.
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