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Loudspeaker Setup Tips


A few preliminaries:

Ground Loops

If your TV is connected to the system (which we most heartily recommend), you have an outdoor antenna, or you get FM from your Cable System, then you need to read the Ground Blocker section of Hi-Fi Tips.


Un-driven Transducers
Anything that is designed to turn electricity into a sound or a sound into electricity can screw up the music.  Some other things that you may have in the room can do this as well.  See the Un-driven Transducers section of Hi-Fi Tips.


Cable & Wire

See the Cable Selection section of Hi-Fi Tips


Feet

Make sure that all loudspeaker cabinets or stands set firmly on the floor via spikes or solid feet (three are self-adjusting, but four are more stable).


Using a Subwoofer?

If so, determine the main loudspeaker placement with the subwoofer removed from the listening room.  See the Un-driven Transducers section of Hi-Fi Tips.


Heavy Speakers?

Although it will handicap your efforts, if the speakers are so heavy that with the spikes on them they cannot be moved with the personnel at hand, you can try all of the following with the spikes removed, replacing and adjusting them once you have decided on the speakers' final locations.


Where?

Usually the initial placement will be based on the way the room is furnished.  For optimum performance you may have to arrange the room around the system.  In some rooms the system works well when placed either way (on either a long or short wall).  In problem rooms (such as those with dimensions that are even multiples of each other) the system may only perform adequately one way, and may even have to be positioned off-center in order to minimize the effect of the room, especially on the bass response.   (To find out why, click here.)


Polarity (Absolute Phase)

Before experimenting with placement, try the speakers wired normally and with the phase of both reversed, as some speaker models are phased wrongly.  (We have even found a model or two who’s correct absolute phasing varies with its placement within the room, which is quite a nuisance.)


Get Started!

Now you can work on placing the main loudspeakers.  Each time you move them you must listen for the accuracy of the pitch relationships of the notes. In the following order, experiment with:
bulletHow far apart the speakers should be (the speakers should usually be kept at least 3 feet from the side walls).
bulletHow far the speakers should be pulled out from the wall behind them.   (Many speakers give their most accurate rendition of pitch and rhythm placed much closer to the wall than the manufacturer recommends.)

(Every room has response peaks, the frequencies of which are dependent upon the room's dimensions.  Commonly, the best sound will be when the distance from the woofer to the wall is 1/2 the smallest room dimension.  To find out why, click here.)

bulletHow much the speakers should be toed-in.  (The music will usually be best rendered when the speakers are pointed somewhere between straight ahead and at the center of your sofa or chair.)
bulletWhether toeing the speakers in altered the optimum distance from the wall behind the speakers.
bulletWhether the optimum speaker spread (distance apart) has been altered by the changes in rear wall spacing and toe-in.

(It is also useful to note that the consistency of the system's bass performance can vary greatly throughout the room.  For info, check the Ripple Applet Page, where you can see what happens when you alter the number and placement of sound sources in a room.  (Click "Stop" then "Edit".  Now move the sources and add or delete sources.  Then click "Calculate" to see what happens.)


Subwoofer

Once you have determined the optimum placement for the speakers, you can bring the subwoofer into the room.  To properly integrate a subwoofer into a system can be a lot of work.  How the subwoofer is connected and how it is placed are both trial and error intensive.

The common wisdom is that the low-frequency signal to the main speakers should be rolled off with the high-pass section of the subwoofer’s crossover (if it has one).  This is said to "clean up" the midrange because the drive unit will have a lot less work to do.  More often than not the degradation caused by the high-pass will be greater than the degradation caused by the driver’s having to reproduce the bass.  We find that you are usually best off leaving the main speakers alone and adjusting the subwoofer so that it merely fills in the missing low-frequency information.

There is much debate about subwoofer placement.  Some say that the center of the wall is best because it gives the same phase & time relationship to each of the main speakers, but others say it’s worst because there are always "dead" spots in the response.  Some say the corner is best because the subwoofer "loads into the room" most efficiently, but others say it’s worst because the room nodes will be excited excessively.  Some say 1/3 or 1/5 of the way along any wall gives the most even frequency response, but others say the "sweet spot" will be room dependent.  Another approach is to temporarily put the subwoofer where your seat is, then listen as you move about the room: where ever the bass response is the smoothest is the place to put the subwoofer.  Assuming that few if any of the "experts" used truly musical criteria to assess the results of their experiments, we recommend the following:

At first place the subwoofer exactly between the main speakers, so that you have the same phase and timing relationships from the subwoofer to the left speaker as from the subwoofer to the right speaker.  Play the system with the woofer "in phase" and phase reversed.  You will also have to adjust the subwoofer level and/or crossover frequency in order to determine which way to phase the sub, as well as to obtain optimum system performance.  This will take a while. (Again, listen for the best pitch accuracy.)  Once you are done, make a note of all the settings.

Try the "subwoofer in your chair" method.  Once you find the "smooth spot", tune the system as above (phase, frequency, and level will have to be tuned).   Once you are done, make a note of all the settings.

(If you have not done so already, click here and here.)

Once you have decided which of the tested placements and settings allow the system to reproduce the pitch relationships most accurately, remove the subwoofer from the room, and listen again.  Did the subwoofer really offer an improvement in musical performance?  If so, great!  If not, sell the subwoofer and get a better CD player, or get another amplifier and passively Bi-Amp the main speakers.  These will always improve the musical performance of the system.

 

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