Speaker placement within the room . .

[jimdgoulding]

and that would include ye olde listening position. Has there been a topic about this? To reveal what our systema are working to deliver, it matters as much any component, er, all components. It's the end game. Comments?

[jimdgoulding]

Well, the picture didn't import. Damn.

[The Grand Wazoo]

From The Grave





Note: The AoS Library needs a good article on loudspeaker placement & how to do it. I'm hoping that reviving this thread will allow us to edit some of its content into a definitive piece on the subject.
At least two of us have been reaping the benefits of taking a second look at speaker placement over the last few weeks, so there are no excuses!

[Alex_UK]

Well, as it was me that resurrected it...

As you can see from above, Jim struggled to get this thread off the ground, (we will forever be wondering what that picture was!) but the essence I think is reasonably clear... Are there any universal "rules" (or at least starting points) for speaker placement? Roughly, I aim for about 6ft between the speakers, plenty of free space around them, and roughly the same distance to me as between the speakers (so 6ft) - to form an equilateral triangle - with the speakers toed in (by about 30 degrees I would estimate.) Tweeters need to be at ear level, and if possible, your head forward from the rear wall.

I recently moved my speakers a foot nearer to my listening position than normal (previously around 7ft away from me) - and the difference was quite staggering - a much bigger improvement even than a new component!

So - any advice on speaker placement, or rules of thumb? As Chris suggested in the "From the Grave" thread, it would be great if we could use this thread as "Intelligence gathering" to write an AoS Library article - so it would be fab to get your experiences and pearls of wisdom.

[goraman]

I learned that tilting them back servery changes the response mostly from the tweeter + 2db. and that toeing out will in general diminish upper mid range. Rear ported will do better bass in corners and closer to the rear wall. Bi polar speakers and electrostatics have to be at least 4 feet into the room from a rear wall and need to have heavy curtains behind them.

Since all speakers seem to have different designs and topology s there really isen't a steadfast general rule. But guide lines maybe?

[YNWaN]

IRear ported will do better bass in corners and closer to the rear wall.

Actually, I would quite strongly disagree with the above - rear ported speakers will produce more quantity of bass if moved closer to a wall (and particularly if placed in a corner), however, the quality of the bass with be poor and my experience (as well as the theory) would suggest that rear ported speakers will produce worse bass if placed close to a wall or corner (worst of all).

[synsei]

That was certainly the case with my Rogers LS55's Dave, which required a bit of space to 'breath'...

[Dominic Harper]

rear ported speakers do not generally like being close to rear walls, the wall will produce overblown bass and swamp the other frequencies. Open baffle speakers are a little odd in that although they do not loke being too close to rear reflections, they are not too bothered by side walls.
Have a look at this http://www.blackseaaudio.com/Sound-files.html
I am working closely with Karl of Black Sea Audio and will be supplying his bass traps etc very soon along with consultation.

[bobbasrah]

Agreed Dominic, but rear ports require that space nevertheless and are rarely at right angles to the wall. Corners (and at the end of the day we all have them and generally that is where the speakers have to go) tend to be the focus of room modes, so trial and error of spacings and toe-in/out is inevitable, without taking account of the needs for domestic harmony. Soundstage and focus is rarely an issue, point and shoot a-la-equilateral, but bass is where the trouble starts. Room modes and divorce are the real challenges, the rest is compromise..

With rear ported, front ported, and TL respectively, the side and rear space requirements are IME less restrictive. Cabinet resonances can induce reactions (I presume this is where OBs score highly), as can the oft forgotten transmission through the timber floor. Strangely, placing wideband absorbers in the corners I've found lessens the space requirements despite being acoustically transparent at those frequencies. Odd.

[Reid Malenfant]

Best system I find is as near as possible an equilateral triangle, with the bass units a different distances (& not a multiple of either) from the side walls to the back wall. That way you minimise the chances of building a massive standing mode at one frequency & spread it a tad.


Nobody appears to have taken into account the way the speaker rolls off in the bass end. This is incredibly important to positioning to get a flat as bass response as possible, & depending on the room size postioning will alter once again to get an optimum balance.

While I do tend to agree about rear ported speakers, you'll generally find that the reason they exit out of the rear is to get a certain amount of wall reinforcement. As an example the Celestion DL6 is tuned to approximately 45Hz with a rolloff that is -3Db at 65Hz or so. Because the driver is in such a small enclosure compared to it's VAS (compliance equivalent volume) it forces it to roll off at 12Db/octave, just like a sealed box. Another effect is that the port output is much lower than normal but spread over a much wider bandwidth & damps the bass driver effectively over the best part of a full octave.

That kind of speaker is designed to get wall reinforcement to boost bass below where it rolls off. Positioned correctly it will have a nice smooth bass down to approximately 35Hz.

Marco's Tannoys have an extended bass shelf response at -6Db to approximately 30Hz, -9Db @ 25Hz. While most people would think they won't or couldn't work in a small room they should work very well indeed due to room gain below the lowest room mode. Again they need to be positioned carefully, but with a rolling off response it's much easier to as it's like they have designed to work in a room & use it to flatten things out into the deep bass.

The problem comes when speakers are designed to be flat & then put in a room, just about no matter where they are placed the bass will generally be overblown