So, you just bought these new Speakers (or build a pair yourself). Where do you put them? I take it for given that most of you, just like me will not be able to afford a special build, acoustically treated listening room with non-parallel but symmetric side-wall, all dimensions following the golden Ratio and so on. If you can build yourself such a room and keep spouse and children out, count yourself blessed and invite me around one day.
On the other hand, if Music is part of Your life then you may
not want to have a separate listening room?
I like having a good sound-system in the room of my Apartment where I spend most of my conscious time.
That means to share the living-room and listening room and likely to compromise. Now still being a Bachelor, I COULD hang my room full of Egg-crates, Tube-traps and Mpingo Dot's.
But I do not. I could not stand it. So audio has to be integrated into the living-environment in a fashion as unobtrusive as possible.
Still, the way you position your Speakers has a profound effect on the Sound you are getting. By positioning your Speakers acoustically correct, you can make all the difference. Reading the various News-groups and E-mail lists, I notice how many people seem to have severe room-problems and try to change equipment to alleviate this. There are interesting products around these Day's that allow you to digitally correct Room-Problems. However, my stomach turns on the very though of turning these nice and intricate analogue patters from my turntable into cold numbers. Also, I sort of currently lack the ready cash for this. If have the green ready, read about the Sigtech AEC-1000 digital time domain room/speaker equaliser and buy one for yourself and send me the other one.
That lacking, we will have to use our own brains trying to find solutions. As I did recently move and moved from an acoustically very nice Living room into an acoustic nightmare my experiences in sorting this out may help. My old living room was relatively large and high (18' X 15' X 11'- good). It had a suspended wood flooring (bad) and a shape and furnishing that suggested itself for Live-End Dead-End set-up (LEDE) with heavy Curtains on the Windows as "Dead-End" behind the listening Position. My new living room is a relatively small square (13' X 13' X 8.5'- bad) with a nice concrete floor (good). Now this room exhibited an extreme amount of Bass-Boom with the 'speakers in the usual positions. It was so bad that listening to music at louder level gave me headaches.
To understand the problems and physics involved a bit better, I suggest you read Placing free-standing control room monitors (PDF) by Genelec. This article views things from the Studio-view things and some of you may sneer at the very idea, but do have read nevertheless. In recent Years various techniques to set-up Speakers in rooms have been proposed. Room set-up by George Cardas suggests doing things using pure math.
I have to say, that while I do understand the underlying principle and the math of both these Methods, in my new room they simply did not work. They also did not work in my old room, as I had my speakers placed alongside the long wall of the Room and not the short wall of the room. In the End I discovered a method for Speaker-Set-Up that worked for me and I dare say will work for you.
My first exposure to the Wilson Audio set-up Procedure (or WASP for short) occurred during my research as to how the Wilson Audio Tiny Tot (WATT) and it's Woofer, the Wilson Audio Puppy (WAP) work. I did this to build my own pair (I was a bit short of the ten grand or so for a good 2nd Hand pair). In his review in Stereophile, Wes Philips went into a great length about WASP and emphasised two things.
One, using WASP does result in relatively living-room friendly positions for the Speakers and two, WASP provides an imaging and sound-staging that is exceptional. Non of the mathematical based Procedures even takes these two into account. WASP will work not only for Wilson Audio 'speakers but for any cone/dome 'speaker system on the market. The only speaker types I would not attempted to install using the WASP rules are: paneltypes, speakers which have specific positioning made mandatory by their designs (such as Klipschorns or Bose designs), various very British Designs which sound decent only when placed directly against the rear-wall (NAIM, LINN come to mind), multi-enclosure systems, such as panel/cone hybrids consisting of a dipole element and a bass tower (Carver Ribbon Speakers and Woofers, Martin Logan Designs).
Still, as boxy 'speakers account for the vast majority of speakers sold, I think that the WASP methodology will be useful to most of you. As you can see from the illustration, all distances are determined using fixed points on the Speaker being set-up as reference.
Click picture for a larger View.
To accommodate any type of speakers, simply stick to the basic angles and to the 1:1.1 to 1:1.25 ratio of listener distance from the speakers vs. Speaker-to-Speaker distance. The triangle in the drawing is a fine starting point to help you locate your listening seat prior to utilising WASP.
As for the distance of the 'speaker to rear wall and the side walls, well, WASP helps determining those distances exactly. Before you start WASP'ing in earnest, make sure the spouse is with the in Law's and the curtains are closed. Otherwise you may reap pointed remarks about the state of your mind if you are lucky (unlucky means the men in white come to "help" you).
Wilson's most basic requirement for WASP is to establish what he calls the 'Zone of Neutrality'. This area is found in every listening room and is usually two to five feet long (60-150cm). It is described as the region most likely to be free of the listening room's most severe acoustical interaction. The first stages of determining the zone will produce a largish area, but at this point the rough dimensions must be regarded only as a basic starting point.
With the aid of a friend who does not mind feeling foolish, place yourself in the target listening position while your assistant speaks in a moderately loud voice at constant level, projecting into the room. Alternatively, use your own voice and walk in similar patterns listen to how your voice interacts with the room. Give it a few tries and listening very hard you will know what it is about. I did it all by myself....
The first step is used to determine the zone relative to the back wall, so the person speaking should start at the back wall, in front of the listening position, walking toward the listening position while speaking. As the speaker approaches the listening position, the voice will appear to 'free up' as it is relieved of the low frequency energy imparted by the closeness to the rear wall. In other words, you are listening for the point in the room where the rear wall stops to reinforce bass. When this point is reached, mark the floor with a piece of Gaffa-tape. You have just discovered the rear border of the Zone of Neutrality.
With the person speaking continuing to walk toward the listening position while talking at the same level, listen for the next change in the voice's tonal quality. This will be the first interaction of the opposite wall and should sound like a loss of focus that seems to resonate because of the side and rear wall reflections. Again, mark the position on the floor when the artifact first appeared with tape. You now have the front and back borders of the Zone of Neutrality.
Using the same procedures, but with the person speaking starting at the side walls and walking across the room in front of the listening position, you can now determine the left and right boundaries of the Zone. Again, as the person speaking walks away from the side walls, you should hear the voice freed of the bass reinforcement provided by the side walls, eventually reaching a point where the opposite wall begins to interact with the voice. Repeat this for the left and right side walls, again marking the borders with tape.
Now if you do this alone as I did, you may find that the borders are marked fairly different for the various walls. Simply using these borders would result in an asymmetrical arrangement of the Speakers. So take some measurements and average all the different Borders you came up with. Then re-arrange the tape to reflect the symmetrical average of your various positions. After performing these procedures you will have two zones, like the squares drawn around the 'speakers in the illustration.
It's time now, to place your speakers in these zones. For the time being, leave off any spikes or feet because you will have to move the speakers about. Sliding them with smooth undersides is a lot easier than dealing with spiked stands or enclosures. If you have not got the floor carpeted (bad Idea acoustically) you may want to put something between speaker and floor that will allow you to slide the 'speakers easily.
Position each speaker in the center of each zone, pointing directly at the listening position. This may seem like an extreme amount of toe-in, but it seems to be the best option. Not only Dave Wilson suggests such extreme toe-in angles. Also Lynn Olson and Joachim Gerhard from Audio Physics suggest such a positioning. You should just be able to see either the inside walls (imaginary lines emanating from the Speakers meet behind the listener) or outside walls (lines meet in front of the listener) of the Speakers.
Next, you should 'calibrate' the floor with tape as shown in the illustration to help you shift the speaker in small increments, l/2" or one centimeter markings should be fine. The strips marked 0-1-0 (parallel to the back wall) should be located close enough to the speakers front-most corner so as to help you to gauge both left-to-right movements and to adjust the amount of toe-in or toe out. Again, you should enlist the help of an assistant for be next phase of the WASP, as it is a royal pain to do it alone. Using a full-range, well-balanced recording played at a moderate level, make notes regarding the sound quality as moves the speakers are moved forward/backward and left/right, using the tape rulers as accurate indication of the position. Thus you can move the speaker as far as to find the point where further movement into this direction does not bring further improvements and still return to the best position.
Listen for the best tonal balance and the ability of the system to portray dynamics as well as the beginnings of good imaging. Conventional wisdom applies here: if the system sounds bass shy, move the speakers back, bass heavy, move them forward. I found a very specific position where the ",Bass Boom" of my square Room was the least. This nearly coincided with the position where all other aspects of my systems performance seemed best too.
With the most important of the rough adjustment being the front-to-back distance, mark the speakers' positions on the floor where the front edge of the speaker would be with tape, so you can always return to this position. The tape should extend beyond the ends of the baffle, because you will be moving the speaker relative to the main rough position. Wilson recommends using the left channel-only of his Ragtime Razzmatazz piano CD for the next part, to fine-tune the position of the speakers relative to the side wall. As I do not have this CD, I use a mono-recording (yup mono and from LP) of the "Unsquare Dance" from the Dave Brubeck Quartet (original released on the "TimeOut" Album).
While the music is playing, your move the speaker with relation to side wall in small increments, while you listen for the 'attack', the dynamic or transient accuracy and how it affects overall harmonic integrity. Now you can fine-tune the toe-in to have the image "snap" into focus, taking care not to alter the front-to-back or side-to-side relationships. Toe-in adjustments mean only the rotating of the speaker on it's centered position. Again, playing a mono-recording is good here. Change the toe-in until the image "focuses" right in front of the Speakers with a good sense of "depth" remaining. You should cross-check using an orchestral stereo-recording (preferably with minimal miking and not multi-tracked). Make absolutely sure that the positioning of the 'speakers is truly symmetric and the degree of toe-in is identical.
Mark the positions again on the tape, refit the spikes and return the speakers to the exact locations indicated by the tape. Now you will get to the last bit of fine-tuning. The height of the 'speaker in the room matters too. What I say now applies specifically to Floor-standing Speakers although stand-mounting 'speakers will also benefit from experimentation. I have found in my new room that raising the 'speakers by about 1-1.5 inch (2.5-4cm) did remove the last traces of "boom". It should be noted that the 'speakers should be level (the Spirit-level from your turntable will work just dandy).
As really tall spikes are somewhat hard to come by, I used large Michell tender-feet cones, M6 bolts, 12 (2.54cm) diameter washers and "chemical metal" Epoxy to improvise tall cones. They work a treat. As I could still notice some boom (very little but notable with certain types of music where already an excess of bass-energy exists on the recording) I placed one Ikea "Bean-Bag" behind each Speaker. Also, my book and record shelves are located behind the 'speakers where they form a reasonably "Dead-End".
Thus using WASP and some small bit's of DIY and "misused" Household items (Ikea Bean-Bag's) turned the Room Of Boom into an eminently listenable environment, into which I can still invite people that are not hard-luck cases of audiophila nervosa. The Speakers are much closer to the wall's than conventional wisdom suggests, further apart and are thus about as "living-room friendly" as it gets. The sound-stage is wide and deep (though I still think I can improve things even further) and the bass is clean, tight and articulate. Maybe my new Speaker-Cables are not entirely innocent here, but that is a story for another Article.
© Copyright 1997 Thorsten Loesch - http://www.tnt-audio.com