Page 1 of Subwoofer Placement

Can someone help?
I have recently bought a DTT3500 Cambridge Soundworks kit.
I know it`s not the ultimate home cinema but it was only £100 from a mate & to be honest the difference in quality from a prologic TV is amazing. I didn`t realise what all the fuss was about Dolby Digital until I got this kit. WOW!! But......................
I have tried various positions of my sub & can`t seem to get it right, but I was wondering in which direction should you face the " port"?
Into the room or towards a wall? Any ideas?
Also at what level should the sub be for movies?

This is pretty much trial and error, Lee. The subwoofer belts out non-directional sound-waves so it doesn`t really matter where you put it - some favour in between the front speakers, others between the rears, yet others on side walls between one front speaker and one rear speaker.

Depends on all sorts of things, the most important one being space. Stick it where you can (hell, I know some people that even use theirs as a coffee table, but I wouldn`t advocate that !).

As for `volume`, well - it`s more to do with output really. Basically if you`re watching a movie that has lots of bangs, crashes and wallops in it, you`ll soon be able to guage whether the bass is taking over the soundtrack. Again, however, this is down to personal taste. I like a good KER-WAPP and a THWUMP now and again, esp. when the neighbours are down the pub.

Half the fun about this home cinema malarkey is getting your soundstage work the way you want to. I`m still not convinced about my rear speaker placement, funnily enough !!!

Happy experimenting

This item was edited on Monday, 19th March 2001, 23:59

Low frequencies cannot be `placed` directionally by the human ear, so in terms of that it is not important, but the soundwaves can interfere with other emmissions from your other speakers - i`d recommend putting it low (on the floor) underneath or behind you.

If you want to drive it louder, put it on a set of spikes and not touching anything that touches walls or floor - that way the sound is in the air, not travelling through the floor and walls, and therefore you can have it louder without annoying your neighbours - you may also get a much tighter, punchier, more focussed sound.

The ideal position for a sub should be on the same plane as the front speakers. Either between the TV and right speaker, or left. Purists tend to go for the right, because this is mainly where the bass element of an orchestra is situated.

The port sucks in and blows out air. This can cause a "chuffing" sound as the air is drawn in and out. You really don`t want to be listening to this, so my advice is to turn the port towards the wall.

The level for the sub is a sod to get right, and depends on your listening preferences for the sound as well. The experts say that you should turn it up loud enough so that you can just about hear it during the normal part of a film soundtrack, and then turn it down one notch.

You shouldn`t be able to hear the sub during normal play. The sub is there to underline bass notes and reinforce explosions. However, at the end of the day, if it sounds right for you... it IS right!

Gilesy

I agree that the `buy the book` volume should be set so that it just starts to enrich the base on normal bit of the film/music.
You should point the sound output away from a wall and at an angle. If it points directly at a wall, standing waves can be set up and give hot & cold spots. This can even happen off a back wall that is several meters away.
Cheers
SteveC

Thanks for the reply.
The sub on this kit is only rated @ 30W so maybe I shouldn`t be expecting too much............but is the content of some DVD`s such that the LFE doesn`t seem to be present?
I have tried X-Men & this is awesome, but I tried The Matrix at the same volume & although I could hear some LFE present it didn`t seem as dynamic or loud, I had to turn the volume up on the amp to achieve this.
Now I know I will not get room shaking effects from this system ( although X-Men & Fight Club come close) but I have played CD`s & the bass is absolutely amazing, so much so that I have to have everything at a lower volume. Why is this so?

Most "real" (ie guitar, piano, woodwind but not electronic keyboards) musical instruments will produce low freq harmonics. These will be amplifies out of all proportion by the sub. I turn mine off for music. It is only really useful for the engineered base that you get on films.
SteveC

The hardest work for an amplifier is to produce low frequencies. It involves a lot of energy to push and pull the speaker cones in and out. What you have done is given the main load of work to the sub`s own internal amplifier, meaning yours doesn`t have to work so hard.

This means the amp spends more energy on getting the rest of the sound right. You generally find that the speakers sound "cleaner" and yes, "louder".

Gilesy.

Good to see you passing on all that subwoofer experience Gilsey ;-)

DanB
DVD Reviewer

For those out there who have upgraded from a stereo amp to and surround sound system don`t throw out the stereo amp with a T-piece connection it could be used as a make shift sub. That is assuming you have another set of speakers kicking around also. Just use the T-piece to turn the mono bass signal out the surround sound amp into 2 and connect as normal to the old amp. Just be careful with the stereo amps volume control as the bass output seems to be set at quite a high level .

I have done this and the results have been very good.....especially when playing any sort of dance music.

Oh the joys of improvisation as a skint student.