subwoofer position?

[looics17]

does the position of the sub really matter? the sub needs to be felt but not heard right. does it need to be pointing in a certain direction? ie towards the central listening position or pointing away from the screen location?

looics

[HDJK]

If you use the crossover function in your receiver the position does matter a lot. It will be the deciding factor wether you have an integrated sound from top to bottom or tiny speakers and an undefined wobble underneath.

A good start is to place the sub at the listening position and then walking around the room. Where it sounds the best is a good starting place for the sub.

[JimPullan]

Yes, the position of the sub does matter and no, a sub carries very low information, like the foot pedal notes from a pipe organ, not simply the boom of an explosion from cinema.

Determining the best location will take time AND two people. One (hopefully you) seated at the prime listening location. The other person will be moving the sub within an arch of 60 degrees from the seated position. The sub being away from the wall and the corner (the corner makes it too boomy). As the second person moves the sub, you'll hear differences, and when you hear the best sound coming from the sub at your location, your done. Use a low bass recording from a CD and play a continuous loop of it as you move the sub around within the arch. A real instrument is better than a test tone for this task. Once you discover the 'sweet spot' for the sub, it will sound wonderful for both cinema and music. Enjoy !!!

Jim Pullan
Audio Excellence
http://www.audioexcellenceocala.com

Originally Posted by looics17

does the position of the sub really matter? the sub needs to be felt but not heard right. does it need to be pointing in a certain direction? ie towards the central listening position or pointing away from the screen location?

looics

[kingofgrills]

Those tips on sub placement are right on. For ideal placement you have to be very methodical with your experimenting. Unfortunately, there are many times where sub placement may be limited due to room geometry or furniture placement. Just do the best you can with placement, and be sure to adjust your levels to help compensate, if necessary.

Also, be sure to check the phase of your subwoofer as well. Often people forget to check that if their sub has a phase adjustment on it.

[Marcusarilius]

Originally Posted by kingofgrills

Those tips on sub placement are right on. For ideal placement you have to be very methodical with your experimenting. Unfortunately, there are many times where sub placement may be limited due to room geometry or furniture placement. Just do the best you can with placement, and be sure to adjust your levels to help compensate, if necessary.

Also, be sure to check the phase of your subwoofer as well. Often people forget to check that if their sub has a phase adjustment on it.

Hi. Can someone explain to me what the "Phase" does on the sub please?

Thank you.

[jomari]

you do it once, you do it right.

try using an sound meter to get the most accurate of response from your subwoofer.

heres a complete article for your assesment.

http://www.soundandvisionmag.com/fea...p-secrets.html

[CAB]

There's a section here with a simple description of phase a easy method of setting it without the use of a tone and SPL meter.

[jomari]

your most important tool to achieving sonic bliss...

http://www.radioshack.com/sm-digital...i-2103667.html

[tofur69]

The phase shift change the cone from pulling to pushing or vice versa. You ALWAYS want your speakers to be in phase with one another. Most speakers have a negative and a positive connection points on them. You should make sure that positive from the receiver is connected to the positive on the speaker. If you reverse it, it will be ok but you must keep it consistant with the rest. Subwoofers alot of the time use RCA connectors just requiring one cable. The positive is the center and the outer shield is ground.

If you reversed the polarity (phase) on the regular speakers (purposely or not), you should make sure your sub matches. Since you cannot do that with a single RCA cable, the switch on it will do it for you.

If two speakers are out of phase from each other, they will virtually cancel each out. This causes dead spots in the sound field. Almost sounds like cotton in your ears.

For you math geeks out there, it will be like comparing a sine wave to a cosine wave. Both waves will cancel each other out.

Hope this helps...

[Marcusarilius]

Originally Posted by tofur69

The phase shift change the cone from pulling to pushing or vice versa. You ALWAYS want your speakers to be in phase with one another. Most speakers have a negative and a positive connection points on them. You should make sure that positive from the receiver is connected to the positive on the speaker. If you reverse it, it will be ok but you must keep it consistant with the rest. Subwoofers alot of the time use RCA connectors just requiring one cable. The positive is the center and the outer shield is ground.

If you reversed the polarity (phase) on the regular speakers (purposely or not), you should make sure your sub matches. Since you cannot do that with a single RCA cable, the switch on it will do it for you.

Hope this helps...

Thank you very much for the great information on Phasing. I just picked up this Sub from Amazon and I hope this one delivers some clean power...
http://www.amazon.com/gp/product/B0000632GP

[tofur69]

That sub should do you nicely. Just make sure your receiver can deliver a clean signal to it. I used to have an older Sony receiver (no HDMI)and the bass from the sub sometimes distorted at high levels and rolled off completely. With my new Yamaha, it was like buying a new sub and speakers. Very clean sounding. No distortion or roll off anymore. The receiver also runs a a self EQ with a mic attachment so it put everything at a proper level so nothing was being strained.

[Marcusarilius]

Originally Posted by tofur69

That sub should do you nicely. Just make sure your receiver can deliver a clean signal to it. I used to have an older Sony receiver (no HDMI)and the bass from the sub sometimes distorted at high levels and rolled off completely. With my new Yamaha, it was like buying a new sub and speakers. Very clean sounding. No distortion or roll off anymore. The receiver also runs a a self EQ with a mic attachment so it put everything at a proper level so nothing was being strained.

Thanks Chris. I have the Onkyo 805. Should be fine. I appreciate your expertise!

[Sylin]

If bass is non-directional, can someone please explain why placement of a subwoofer is relevant? Provided it is in the same room, and isn't being artificially drowned (by being behind a big piece of furniture) or enhanced (such as sitting in a corner), then shouldn't putting it in an open part of the room be good enough? All this talk of finding a "sweet spot" by moving it a few inches left or right seems like FUD to me.

[musicman1999]

Furniture, wall covering even the number of people in the room have an effect on the bass.All these things combined with the room shape create room or bass nodes the cause irregularities in bass response.Proper placement is key.

bill

[jomari]

Originally Posted by ikcizokm

If bass is non-directional, can someone please explain why placement of a subwoofer is relevant? Provided it is in the same room, and isn't being artificially drowned (by being behind a big piece of furniture) or enhanced (such as sitting in a corner), then shouldn't putting it in an open part of the room be good enough? All this talk of finding a "sweet spot" by moving it a few inches left or right seems like FUD to me.

its about how the subwoofer would perform in certain locations.

for example, if you places it closer to a corner you get yourself 'greater output' (but not necessarily cleaner) than that to it located farther.

its also about experimenting and finding the appropriate location for your subwoofer to get a 'cleaner' sound.

albeit bass is non directional, you also want to make the most out of it, using it efficiently to provide you with what sounds best to you.you also want to make sure that it doesnt cancel out the fronts, and or cause any time delays. Thats why some people 'prefer' to place it in the front area/soundstage of the room and not necessarily at the rear part.

as per an article in audioholics forum...

http://www.audioholics.com/tweaks/sp...ent-guidelines

some reading material...

http://www.sencore.com/newsletter/Ju...alibration.htm

and lastly,

http://www.axiomaudio.com/newsletter_index.html

how fud is that?

[Sylin]

Originally Posted by jomari

its about how the subwoofer would perform in certain locations.

for example, if you places it closer to a corner you get yourself 'greater output' (but not necessarily cleaner) than that to it located farther.

its also about experimenting and finding the appropriate location for your subwoofer to get a 'cleaner' sound.

albeit bass is non directional, you also want to make the most out of it, using it efficiently to provide you with what sounds best to you.you also want to make sure that it doesnt cancel out the fronts, and or cause any time delays. Thats why some people 'prefer' to place it in the front area/soundstage of the room and not necessarily at the rear part.

as per an article in audioholics forum...

http://www.audioholics.com/tweaks/sp...ent-guidelines

some reading material...

http://www.sencore.com/newsletter/Ju...alibration.htm

and lastly,

http://www.axiomaudio.com/newsletter_index.html

how fud is that?

OK, well, that answers my question. Thanks.

I wasn't trying to condescend... just wanted to be sure there was some actual merit behind this, as opposed to one of those "urban legends" that CE companies use to sell products and services.

[HDJK]

Some more links:

http://www.audioholics.com/tweaks/ge...r-calibration/

http://www.audioholics.com/tweaks/ge...or-bass-part-1

http://www.avforums.com/forums/showthread.php?t=176978

[jomari]

Originally Posted by ikcizokm

OK, well, that answers my question. Thanks.

I wasn't trying to condescend... just wanted to be sure there was some actual merit behind this, as opposed to one of those "urban legends" that CE companies use to sell products and services.

well, it did somewhat come across that manner, considering that you mention fud in the first place. i dont see any fear uncertainty and doubt in any myths regarding subwoofers...

urban legends or myths as you would call it, would be in my opinion be bi-amping, or bi-wiring speakers. or the fact that certain wiring products give exponential results compared to other 'non-branded' ones.

when you start learning a lot more about how to tweak your system, finding how much an effectiveness you can manage to pull from it.

try using a spl meter, and calibrate your sub to see how good it can perform, and experiment with it. it always is a bit of a hassle, but well worth it once you get both your fronts and your sub to work hand in hand.

[richteer]

Originally Posted by jomari

urban legends or myths as you would call it, would be in my opinion be bi-amping, or bi-wiring speakers. or the fact that certain wiring products give exponential results compared to other 'non-branded' ones.

The positive effects of bi-wiring (and bi-amping) are anything BUT urban myth. I have heard improvements with every bi-wirable speaker that I've bi-wired.

My first experience with bi-wiring was years ago, with a pair of Tannoy Mercuries. Being a sceptic, I was curious to see what effect (if any) bi-wiring would have, so I modified the crossovers to allow bi-wiring. I was amazed at the result, and have been an advocate of bi-wiring ever since. (I guess it is possible that some speakers are so crappy that bi-wiring won't help, but I think anyone using those wouldn't be interested in bi-wiring in the first place!)

I've heard changes in cables too, but that's another story. :-)

[jomari]

Originally Posted by richteer

The positive effects of bi-wiring (and bi-amping) are anything BUT urban myth. I have heard improvements with every bi-wirable speaker that I've bi-wired.

My first experience with bi-wiring was years ago, with a pair of Tannoy Mercuries. Being a sceptic, I was curious to see what effect (if any) bi-wiring would have, so I modified the crossovers to allow bi-wiring. I was amazed at the result, and have been an advocate of bi-wiring ever since. (I guess it is possible that some speakers are so crappy that bi-wiring won't help, but I think anyone using those wouldn't be interested in bi-wiring in the first place!)

I've heard changes in cables too, but that's another story. :-)

true, but to a certain point. i find it pointless to biamp or biwire speakers IF you are using a mid-range reciever. as to certain points, you will get its benefits if you, how do i say it, have the proper equipment to use.

passively bi-amping is using the same amplifier to power both speakers, thus ineffective. In an active bi-amping situation, the woofer amp is only reproducing the bass and the tweeter amp is only reproducing the treble. This is where all the efficiencies of bi-amping are realized

Passively Bi-Amp Speakers are when two amplifer channels are used, one for the high frequency and another for the low frequency. The straps that connect the posts together on the speaker are removed (very important).

In an Active Bi-Amp Speaker setup, the crossovers are removed from the speaker system and an active crossover is placed in front of the amplifier channels. This way the amplifiers are directly coupled to each speaker. It is VERY important the active crossover be used and adjusted correctly for the speakers being used.