Do you guys subscribe to Cardas math for speaker distance from front wall?

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bmckenney

Here's some other positioning methods/tools:

http://www.barrydiamentaudio.com/monitoring.htm

http://www.hunecke.de/en/calculators/loudspeakers.html

http://www.higherfi.com/speaker_position.htm

Barry's approach says it's a simpler approach that combines Cardas and Thirds.  I can't say it's simpler than Cardas.  You can't get more simple than entering the room width in to the Cardas calculator and putting your speakers in the location.  And I do not see how it incorporates the Cardas approach, it seems to be basically the rule of thirds to me.  And the rule of thirds can result in the speakers out further than the front wall than what Cardas results in.

The hunecke calculator gets a big A for effort and aspiration.  Interestingly it gives me the same results for distance from the front wall as the Cardas dipole math.  But the distance from the side wall is closer in, which I think is a big mistake.

And the Higherfi approach seems pretty bizarre and a lot of work.

Thanks for adding the links to the thread.

Bryan

bunnyma357

Couldn't find any info online with just the words Master Set.  Suggestions?  In a rectangle room, how could speakers be out of phase if they were positioned exactly the same with no large objects obstructing their radiation?  Thanks, I don't understand this statement.at it didn't ask for the length.  Am I missing something?  Thanks.

http://www.audiocircle.com/index.php?topic=64320.0
http://www.audiocircle.com/index.php?topic=64321.0
http://www.audiocircle.com/index.php?topic=65908.0

Jim C

stvnharr

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I don't doubt that Master Set is a good method.  I've heard too often that it works.  The benefit you say it results in, the one sound  source in the room affect, is exactly what Cardas can provide too.  It's what I hear.  What I like about the Cardas method is how much easier it seems to be to setup compared to Master Set.  Master Set is a lot of work.

Bryan

Okay, just a few things.
If both speakers are acting together as a single sound source, in correct Master Set alignment, the sound is stable from anywhere in the room. It doesn't move with you when you move. A singer's voice in the middle will always stay exactly in the middle no matter where you sit in the room.
I listened to Cardas sets for years, the sound always moved when you moved. The sweet spot of listening is pretty small.

In a correctly designed speaker, all the drivers in the one speaker should be in correct phase with each other.  That's for that one speaker only.  But what I am referring to is one speaker to the other speaker, as they sit in the room.  It's a difficult concept to understand because everyone just assumes the two speakers are in phase with each other automatically. In anything other than a MS alignment in the room, there is a small phase variance between the speakers which manifests itself much as intermodulation distortion in an amplifier.  Everyone has heard this forever and doesn't know that it exists. When you hear a properly done Master Set, this distortion is removed and you get a clarity of sound that will stun you.  It certainly did me.

If you want to read more about Master Set, there is a thread on the Aspen Forum.  Also, you can do a search on the audiogon forums for Master Set or Iron Chef.

It's difficult to do as a diy'er. Easy/difficult is irrelevant to the end result. When you've got it done, you're done. Whether it took 20 minutes or 3 hours is irrelevant a day or week or years later. It's what you end up with that counts.

If you want to read more about Master Set, there is a thread on the Aspen Forum.  Also, you can do a search on the audiogon forums for Master Set or Iron Chef.

PS. Easier to just add to this post that write a new one.
After re-reading the original post, a refreshment with the full Cardas site, which now has a lot more information on it than when I last looked, and a couple google searches on Golden Cuboid and Fibonacci numbers, a few things pop into my head.
George's nearfield and long wall setups are fairly good designs.  The equilateral triangle will always give a good sound, though with a smallish sweet spot.  But if you only listen my yourself, it's fine.
Most people set up speakers on the short wall as it just seems to be the most convenient thing to do.  I always used to do this too.  BUT, you are always subject to sidewall reflections no matter how you do it, unless you sit up close.
All I can add otherwise is that after being all around the wheel with setting speakers, Master Set is a far cut above anything else.


« Last Edit: 22 Nov 2009, 11:15 pm by stvnharr »

stvnharr

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stvnharr, what are the dimensions of the room and location of your speakers?  I am curious if the position is the same as the Cardas approach.  The original purpose of the thread was to get some feedback on how far people locating their speakers out in to the room.

Master Sets are always done along the long wall of the room.  They are generally not far out into the room.  The rear of the speaker will be 12-18 inches out from the wall.  How far out the front baffle is depends on the depth of the speaker cabinet. There's always a pretty good toe in, and the speakers are 2 1/2 to 3 feet away from side walls.  Final positioning is all done by ear, and generally looks fairly similar to most other close in placements.

Cardas usually get you out somewhere around 5 feet into the room.

vinyl_lady

Bryan,

Thanks for starting this thread. I have been following it, learning a lot and experimenting with my speaker location. My room is 17' x 25' with a 17' peak cathederal ceiling on a 9/12 slope. I have a 57" rear projection HDTV the speakers that extends 25" into the room.I worked with Rives Audio on an acoustic treatment package for the room that included accounting for the TV. I cover the reflective front of the TV with an afgan throw when listening to music. The room is described in my system posting link in my signature block. Rives calcualted the distance from the fornt of my woofer to the wall behind my speakers (he leaves the side wall distance to the listener through trial and error). At the time I was listening to B & W Matrix 804s. When I purchased the Daedalus Audio DA-1s in 2006, Richard recomended that I bring them out into the room 8 to 14". I had the Deadalus about 44' from the side walls, 68" from the wall behind the speakers and was satisfied with the sound.

After reading some of the posts, I used the Cardas calculator and moved my speakers 56.25" from the side walls per the calculation. All I can say is WOW! Insturments became more focused, much better bass extension, detail and slam. I am hearing the individual strings of a bass guitar on good bass runs. There is greater clarity, more "air" around the different instruments. What amazed me is that the center stage instruments and vocals actually seem to move back in the soundstage--more recessed as Jim has posted. The Daedalus DA-1.1s have two tweeters offset by 10 degrees with gives me a very wide sweet spot and speakers that fill the room with sound. In the new location the sound remains stable when I move out of a center listening postion. I still have a wide soundstage but there has been a marked improvement in focus, detail and soundstage depth. I don't sense that I have lost any warmth.

The speakers are 72" from the front of the woofer to the wall behind the speakers, an increase of 4" and still within the Rives calculation (68 to 74). The Cardas calculator would locate the speakers 91" from the wall behind the speakers, which puts them too far out into the room given that the room also doubles as a family/entertaining room. My listening position is 11' from the speakers and the speakers are 7' 6" apart (center of woofer to woofer).

The Cardas calculated distance from the side walls sure made a noticable improvement. Count me among the believers on the side wall distance. Rives took into account my furniture, the big TV, etc. when he designed the treatment package and claculated the front distance. That distance which is 19' less than Cardas works great in my room. Here's a picture (more are posted in my gallery)


Happy listening to all,

Laura
 

Wind Chaser

My room is 17' x 25' with a 17' peak cathederal ceiling on a 9/12 slope.

Excellent.  That's the kind of room I wish I had.  I've never used a "formula" to set things up, just my ears.  The basic principle that works for me distance.  The more the, the merrier!  As a kid I use to take my gear outside at every opportunity and turn things up loud when parents were out.  Things always sounded much better outside than in, the only exception being Magnepans.  Never bothered with taking my Acoustats outside, too much hassle, but because they are so directional, they seemed to be less impervious to the sidewalls.  They also required considerably more effort to get set up right. 

JackD201

All the methods listed including the Audio Physic methods are all starting points worth considering. That's all they though, starting points.  The biggest danger is to follow the methods to the letter and then condition one's self that THAT is the correct sound instead of trusting one's own instincts.  Personally, I've tried them all and all work well enough. The limiting factor has never been the method in use itself but rather practical considerations like total usable space, listening position/furniture layout, access to doors and storage, access to the wall outlets and where to place the equipment racks. Sooner or later compromises will need to be made especially taking into consideration bare room acoustics. All these will probably make one stray from the presets of the methods. My point is that it's okay to stray for as long as the end result is satisfying.

The beauty of trying to optimize as many method (as well as experimenting with speaker height and rake angles) one can is that in time the interactions between loudspeakers and rooms becomes almost instinctive turning you into a human ray trace machine and will prepare you for setup of even the strangest rooms like those we routinely face at trade shows. All this work plus the added benefit of a good bunch of workouts makes me very supportive of the said methods.

bmckenney

Laura, you have a great room and acoustic treatment.  Definitely worthy of all the nice components you have too.  Or vice versa.  It is great to see someone who went beyond just having nice equipment.  I'll bet a midfi system would sound great in that room, assuming good speaker placement.

I'm glad to hear the distance from the side wall made such a big difference for you.  I think it is a pretty important parameter, maybe even more so than distance from the front wall when using direct radiators.  It is interesting that with such a nice system and acoustically treated room, and with help from Rives, you can still make such a big difference using the Cardas approach for sidewall placement.  I've been thinking a lot lately about pictures I've seen of nice systems with acoustic room treatment and what looks to me like poor speaker placement.  I see all kinds of pictures like this on websites including GIK and Real Traps.

Is there any way you can move them out to 90 inches just to see how it sounds, even though you have to move them back?  I'd love to know if it makes a big difference with your speakers and room.  My theory is it might not because your speakers are not dipoles, which I think might be more sensitive to the front wall distance.

Bryan

bmckenney

All the methods listed including the Audio Physic methods are all starting points worth considering. That's all they though, starting points.  The biggest danger is to follow the methods to the letter and then condition one's self that THAT is the correct sound instead of trusting one's own instincts.  Personally, I've tried them all and all work well enough. The limiting factor has never been the method in use itself but rather practical considerations like total usable space, listening position/furniture layout, access to doors and storage, access to the wall outlets and where to place the equipment racks. Sooner or later compromises will need to be made especially taking into consideration bare room acoustics. All these will probably make one stray from the presets of the methods. My point is that it's okay to stray for as long as the end result is satisfying.

The beauty of trying to optimize as many method (as well as experimenting with speaker height and rake angles) one can is that in time the interactions between loudspeakers and rooms becomes almost instinctive turning you into a human ray trace machine and will prepare you for setup of even the strangest rooms like those we routinely face at trade shows. All this work plus the added benefit of a good bunch of workouts makes me very supportive of the said methods.

I really don't think the Cardas placement is a starting point in the sense I think you mean.  I suspect you'd not deviate much at all from the math if you were to try some experimentation.  I agree with the living space limitations being a big problem.  I still managed to get my speakers in the best room acoustic position and have furniture in and around the speakers which is not ideal, but at least the speakers are in the best location.

Bryan


bmckenney

Cardas usually get you out somewhere around 5 feet into the room.

Really?  It's based on a ratio of the room width (and ceiling if dipole).  I don't know why you would think that.

Bryan

vinyl_lady

Laura, you have a great room and acoustic treatment.  Definitely worthy of all the nice components you have too.  Or vice versa.  It is great to see someone who went beyond just having nice equipment.  I'll bet a midfi system would sound great in that room, assuming good speaker placement.

I'm glad to hear the distance from the side wall made such a big difference for you.  I think it is a pretty important parameter, maybe even more so than distance from the front wall when using direct radiators.  It is interesting that with such a nice system and acoustically treated room, and with help from Rives, you can still make such a big difference using the Cardas approach for sidewall placement.  I've been thinking a lot lately about pictures I've seen of nice systems with acoustic room treatment and what looks to me like poor speaker placement.  I see all kinds of pictures like this on websites including GIK and Real Traps.

Is there any way you can move them out to 90 inches just to see how it sounds, even though you have to move them back?  I'd love to know if it makes a big difference with your speakers and room.  My theory is it might not because your speakers are not dipoles, which I think might be more sensitive to the front wall distance.

Bryan

Thanks Bryan. I appreciate your comments on the room and gear. I feel very blessed.

I think I got a little lazy initially with the side wall placement, thinking that after treating the room per the Rives design that an equilateral triangle between the speakers and my listening position would sound as good as any as long as I used the Rives calculation for the forward position. I found out last night and today that my assumption was wrong. Even with an engineered-designed acoustic treatment package, moving the speakers out from the side walls per the Cardas formula made a big improvement in the overall sound. The equilateral traingle method placed the speakers too close to the side walls which muddled the sound, especially the bass, compared to what I hear with the speakers farther from the side walls. It wasn't that the sound was bad before, it's just that it is better now.

Richard Bird told me that side wall placement required listening and moving and more listening and moving until you get it right. I should have listened to him and experimented with side wall placement before now. :duh: In the course of moving my speakers last night and listening today, I tried different distances between where I had them and where they are now. I like the current position the best. I've been experimenting with toe in today and I think I'm pretty close.

I will give the 91" position a try later in the week when I have some time off from work for the Thanksgiving holiday and post on it.

When I saw Richard Bird at RMAF, he suggested that I experiment with some diffusion in front of the TV. I think I'll start a thread and see what thoughts and ideas some of our AC friends might have.

Happy Thanksgivng to all,

Laura

bmckenney

Laura,  it sounds like you had a good weekend on the speaker placement front since you managed to fill in that piece of the puzzle you were lazy about!

I'd really like to read a post from you later this week regarding how the change in front wall distance sounds.  I'm trying to learn as much as I can about placement but a guy can only experiment with what he has on hand which is quite limiting.

Bryan

stvnharr

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Cardas usually get you out somewhere around 5 feet into the room.

Really?  It's based on a ratio of the room width (and ceiling if dipole).  I don't know why you would think that.

Bryan

I realize it's all about the math, and it would be different for every room and dimension.

BTW, I listen mostly to classical music, and I always found the Cardas sets really ruined string quartet playback, as the speakers were just too far out into the room.  Although, it did allow me to put a chair behind the speakers and sit behind the music. 

UM, I'm really not much help in the query of your original post, I'll try not to be a bother any more.
I think Master Set is the best way to go, period.

PS. The sound that you hear in audio playback is made by the speaker energizing the air, whether it be by pistonic motion, film vibration, or whatever. This air pressure then makes your eardrum move, which your brain interprets as music.  Yes, I know, simplistic, but it's what happens.
Every speaker has a slightly different frequency balance and dispersion into the room.  Every room is different.
A mathematical formula makes like everything is the same, when it's not.


jhm731

Here's some other positioning methods/tools:

http://www.barrydiamentaudio.com/monitoring.htm

http://www.hunecke.de/en/calculators/loudspeakers.html

http://www.higherfi.com/speaker_position.htm

Barry's approach says it's a simpler approach that combines Cardas and Thirds.  I can't say it's simpler than Cardas.  You can't get more simple than entering the room width in to the Cardas calculator and putting your speakers in the location.  And I do not see how it incorporates the Cardas approach, it seems to be basically the rule of thirds to me.  And the rule of thirds can result in the speakers out further than the front wall than what Cardas results in.

The hunecke calculator gets a big A for effort and aspiration.  Interestingly it gives me the same results for distance from the front wall as the Cardas dipole math.  But the distance from the side wall is closer in, which I think is a big mistake.

And the Higherfi approach seems pretty bizarre and a lot of work.

Thanks for adding the links to the thread.

Bryan

Look how close the speakers are to the side walls in this installation:
httpP://www.avguide.com/forums/wilson-x-2-installation-rhs-house

Until the Master Set folks post some measures, I think all of them are listening to a pleasant bass boost like engaging a loudness contour switch.





jimdgoulding

After using the Cardas calculator, I discovered that I had moved my speaks actually closer together at 44" from my side walls (56" apart) and I came back to this.  I have positioned both my chair and my speaks 54" off the front and back walls.  This is all from center to center and includes the toe in (less than before) of my speaks.  Orchestras are behind my speaks and spread out independent of speaker placement and my room's walls, it seems.  Depth is excellent.  Close your eyes, and yer there!  Close miked music is more in the room.  So, my experience from reading this and using Cardas as a starting point has made my speakers more transparent to the event.  I'm less aware of them and my room and more aware of the venue and what's happening, clearly.  Tone is just fine to the limits of my speaks and things are more convincingly real.  This thread done good here.  Happy trails and thanks for the upgrade.

If anyone wants to know, my room is actually (re-measuring) 14'x12'x8'. 
« Last Edit: 23 Nov 2009, 11:49 pm by jimdgoulding »

stvnharr

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Until the Master Set folks post some measures, I think all of them are listening to a pleasant bass boost like engaging a loudness contour switch.

In a word, NO.

Perhaps you should reserve any opinion or judgement on Master Set until you hear a Master Set, rather than idly speculate from no real information.

JackD201



I really don't think the Cardas placement is a starting point in the sense I think you mean.  I suspect you'd not deviate much at all from the math if you were to try some experimentation.  I agree with the living space limitations being a big problem.  I still managed to get my speakers in the best room acoustic position and have furniture in and around the speakers which is not ideal, but at least the speakers are in the best location.

Bryan

Hi Bryan,

All the methods start with the premise of a rectangular room but not the symmetry of construction materials and their corresponding material densities or their surface textures for that matter. In a case for example that the ratios are spot on but say on the left wall you have dry wall and the right wall you have poured concrete or plaster over hollow blocks some minor adjustments in position may be beneficial. The dry wall will absorb bass energy and possibly even resonate at high SPLs while the CHB or poured concrete will just launch all that bass back into the room. Same goes for drapes on one side and bookshelves on the other when it comes to the upper octaves. This is what I meant by the dangers of taking the calculations to the decimal. In a regularly shaped room that's irregularly finished at least in my experience and opinion there is no harm in trying deviations from the "numbers" in order to further smooth out frequency response at the points of summing aka the points of phantom image definition. A bare left side will pull the image in that direction when the right side is more absorbent while it simultaneously tilts the HF upward. Also the methods if I'm not mistaken were devised for use with front firing box speakers. The dispersion pattern of the particular speaker's mids and highs if they are omni, dipole, or super-cardioid will again differ from the recommended positions. Only the onmi bass regions would be applicable with the models listed.

Anyway, my main point is that playing with speaker positioning can bring great benefits for free so there really is no harm in trying any of them. Being that this hobby of ours depends on personal preference I'd just like to see each and every music lover dial in his own sound. If someone likes a bit of boom and he wants to deviate a bit by locating his speakers nearer the front wall or altering the ratio between front wall and sidewalls, I say "whatever makes ya happy" and I mean it too :)

Jack

Carl V

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Ditto to what has been said above.
It's a very good starting point.

My home setup used the Cardas &
"master's set-up" as a guide to good effect.

Interestingly enough going out to California
and hearing SL Orions in both his home & at the
Beach house was enjoyable.  Nice sound. Simple
set-up no room treatments per se.  Reading Mr
Floyd Toole's book reinforced SL set-up.  Along these
lines many moons ago I heard Dunlavey's set-up.  Long wall
toe in with minor room treatments.  Again damn nice sound.
Have you ever noticed that Bobby of Merlin, DeVore have
consistiently good room set-ups?  And it usually resembles
a rule of 1/3 or Cardas setup.  Nice starting point.

Clearly a one size fits all approach won't always work.

cheers

stvnharr

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[
Anyway, my main point is that playing with speaker positioning can bring great benefits for free so there really is no harm in trying any of them. Being that this hobby of ours depends on personal preference I'd just like to see each and every music lover dial in his own sound. If someone likes a bit of boom and he wants to deviate a bit by locating his speakers nearer the front wall or altering the ratio between front wall and sidewalls, I say "whatever makes ya happy" and I mean it too :)

Jack

Nice post Jack.