[DMurphy]

I'm still having trouble understanding how toe-in can affect bass response.  Bass waves are omnidirectional--a pulsating sphere.  If you rotate a sphere, you've got a sphere.  I guess maybe the two spheres will be a little closer together if you toe in, but you could get that effect by just moving the speakers slightly closer to each other.

[adydula]

I can understand how you feel about that...and I agree with you for the most part...but I think its more like when you position a subwoofer...it works better in some postions vs others...we crawl around the floor looking for the best spot for the sub..I think the bass is being influenced on by the realtaionship to walls, the ceiling, refelections etc...we arent talking about 20Hz notes...its the 40-60 + hz stuff that seems to be affected here....some speakers dont seem to have any effect but most of the ones i have owned seem to suffer from this in some way or another...

Have you tried this and what are your results??

Alex

[Wayner]

I don't think toe-in really affects bass response unless you have a rear ported speaker and you are near a corner, then you would get horn effect. I think the toe-in only affects the fill-in of off-axis response and perhaps too wide a distance between speakers (which in some cases) may be restricted to certain areas in a listening room by architectural features, like a fire place or some kind of bookshelves.

What adydula is talking about is the 6/6/6 rule. Speaker close to the back wall gains 6db of bass, lower it so it's close to the wall and close to the floor, gain another 6db. Move it close to the first wall, keep it close to the floor and move it close to the 2nd wall (now your in a corner) and gain another 6db in low frequencies. Of course, now it is a boom-box. That is not what I refer to as toe-in, that's just plain moving the speaker into a corner.

Wayner

[DMurphy]

I can understand how you feel about that...and I agree with you for the most part...but I think its more like when you position a subwoofer...it works better in some postions vs others...we crawl around the floor looking for the best spot for the sub..I think the bass is being influenced on by the realtaionship to walls, the ceiling, refelections etc...we arent talking about 20Hz notes...its the 40-60 + hz stuff that seems to be affected here....some speakers dont seem to have any effect but most of the ones i have owned seem to suffer from this in some way or another...

Have you tried this and what are your results??

Alex

Bass is still omnidirectional at 60 Hz--and with most normal baffles the transition to hemisphere radiation doesn't begin until 200 Hz, becoming complete around 1 kHz.  You're certainly right that the placement of a sub is critical--but that has to do with the distance from surrounding boundaries, not swiveling the sub about its axis.  I guess the point about port orientation is valid, although the effect would be tiny--really tiny--unless you started with the port slam up against the back wall. 

[Wayner]

Dennis,

In my case, my Paradigm Atom is smack against the wall. Very little movement will alter it's bass response lots. And that movement gets amplified as I move towards the quasi-corner trippler. I agree that bass notes below even 80 hz are not polarized, but they can be amplified by boundaries. I have a subwoofer in my main system that is off to the right main speaker, to the outside, but not in the corner (kind of close 4 feet maybe) and it is very effective there. The bass is simply omni-directional in its position. It truly sounds like it is coming uniformly from the entire listening room. Ask Frank Van Alstine about it. He's heard it.

Wayner  aa

[DMurphy]

I don't doubt it in the least.  I think that's constent with my comments.

[adydula]

Boundries is a good way to describe what I have experienced. My pair of bass reflex Dahlquist QX10's with a rear port are 20 or so inches from the rear wall and 20 inches or so from the side walls, and when they are facing straght out, parallel to the side walls they sound boomy, and when toed in a little bit,2 inches or so the boomy goes away. We arent really close to the walls so the 6/6/6 rule is not applicble here, but the 6/6/6 rule does apply when you get close to the boundries...I only know by playing with the positioning and listening and listening you will hear differences and it takes some playing with to ge the best out of your speakers and your room.

When I first got in the HT stuff I was really in to calibrating the speaker level with a SPL meter, and what a difference this did...then i discovered Audessy and DTS Master Audio and another learning curve and another level of exploration and learning...I wish there was a tool or device we could plugin to a PC and have it guide us thru some simple measurements with reference tones to get us in the ballpark etc...

Maybe this exits but i am ignorant in this area,,,

Alex

[zybar]

Boundries is a good way to describe what I have experienced. My pair of bass reflex Dahlquist QX10's with a rear port are 20 or so inches from the rear wall and 20 inches or so from the side walls, and when they are facing straght out, parallel to the side walls they sound boomy, and when toed in a little bit,2 inches or so the boomy goes away. We arent really close to the walls so the 6/6/6 rule is not applicble here, but the 6/6/6 rule does apply when you get close to the boundries...I only know by playing with the positioning and listening and listening you will hear differences and it takes some playing with to ge the best out of your speakers and your room.

When I first got in the HT stuff I was really in to calibrating the speaker level with a SPL meter, and what a difference this did...then i discovered Audessy and DTS Master Audio and another learning curve and another level of exploration and learning...I wish there was a tool or device we could plugin to a PC and have it guide us thru some simple measurements with reference tones to get us in the ballpark etc...

Maybe this exits but i am ignorant in this area,,,

Alex

Here is a very promising tool:

http://www.xtz.se/produkt.php?allmant=true&produkt=41&eng=true


I ordered one and hope to have it shortly.

George

[Wayner]

Alex,

You do have 2 good tools to use that are right in your house. They are called ears. I really try to use these suckers when ever I can. A good test record or CD is a good tool as well. I've gone down that perfection road a time or two, looking for the "perfect" speaker position. I think it's reaching for grapes in most cases. We do know there are some general rules, as Dennis and others have pointed out, but in the end it's how it sounds when you plop yourself down in your favorite chair and start a listening session.

The best solution to this whole speaker placement problem is experimentation. You now know some of the general rules of behavior of sound. I think the major mistake most people make is that they get into to big of a hurry to get the speakers final resting place. Take your time. make small movements and listen to a variety of music when you put it into a new position. It takes the brain awhile to get used to the new position. Sometimes the new position can be sour grapes immediately, sometimes, you realize it was the greatest spot ever, especially the next day or 2.

Anyway, if you have Songtowers to have the problem with, luck you!  aa

Wayner

[adydula]

Wayner...

I ordered a pair of QWT's a few days back and am waiting patiently for them to arrive.

Yes the best tools are our 'ears' for sure if used properly!!

Like dont drink a lot before using them 

I have been out of the limelight with the audio scene for many years and its great to be back again.

I didnt even understand what MTM even meant!!!

The Dahlquist QX10's are a bass reflex design with three 5" mid woofers and the one titanium dome tweeter..with the tweeter on the top
so I guess this means they are a MMMT or is it a TMMM!!   

When I ran the Audessy program in my receiver I was in amazement on how it can do what it does....its magic to me!
And when it was done it was like 'WOW' this is different and I am glad it as in the 'better' direction to me.


When I had a pair of first generation Mirage M1's (180 pounds each) I had a marvelous time finding 'the spots for their placement' and look forward to playing again...but the room I have now is the 'one over the garage' room, and its not that big or forgiving....but we are up for the challenge!

With the Mirages I had a room built for them using good ole Paul Klipsch's Golden Mean Room specs...had the room double sheetrocked, plywood was glued and screwed and I can honestly say it was a pretty good room...especially after a beer or two!! 

Ok back to the waiting and other hobbies like my photography!!

Alex



George,

This looks neat...I wonder how it relates to what Audessy does, look this software presents you what the room looks like and its ' capabilities" while the Audessy right or wrong does this and makes the changes in the hardware/firmware of the electronics to apply it....I wonder if you have to take the output or recommendations of this program and manually crank it in to your electronics at the right place's'?

Alex

[zybar]

Alex,

You do have 2 good tools to use that are right in your house. They are called ears. I really try to use these suckers when ever I can. A good test record or CD is a good tool as well. I've gone down that perfection road a time or two, looking for the "perfect" speaker position. I think it's reaching for grapes in most cases. We do know there are some general rules, as Dennis and others have pointed out, but in the end it's how it sounds when you plop yourself down in your favorite chair and start a listening session.

The best solution to this whole speaker placement problem is experimentation. You now know some of the general rules of behavior of sound. I think the major mistake most people make is that they get into to big of a hurry to get the speakers final resting place. Take your time. make small movements and listen to a variety of music when you put it into a new position. It takes the brain awhile to get used to the new position. Sometimes the new position can be sour grapes immediately, sometimes, you realize it was the greatest spot ever, especially the next day or 2.

Anyway, if you have Songtowers to have the problem with, luck you!  aa

Wayner

Wayner,

While the ultimate decision maker for me is my ears, I have found it invaluable having tools to assist me in my quest for maximizing my setup's performance.

Something like the XTZ Analyzer will allow a person to do things for a few hundred dollars that would have cost tens of thousands of dollars not too long ago.  Here are a few tasks it can perform:

    * Frequency response - RTA (Real Time Analyzer)
    * Frequency response, bass area (High resolution)
    * Finds room nodes and calculates the necessary compensation to correct them
    * Spectrogram/reverb time (Time/frequency/magnitude)

All of these will help a person dial in their system in a systematic and measureable way.  IMHO, it also "teaches" a person why when they move their speakers, listening position, room treatments, etc...it impacts what they hear.

Now, the tools of the trade aren't always hi-tech.     Things like pen and paper to write down your thoughts, distances, etc...Is an absolute necessity; as is using some masking tape to mark exactly where speakers and the listening position were located.

George

[Wayner]

I agree George, looks like a very neat tool. Don't get me wrong, I'm not against using technology to help fine tune the speaker positions. I just know some people are going to get ultra fanatical about things like this and wear out their carpet or floor moving, moving and more moving. Let us know how it works out and how easy/difficult it was to use.

One trick that I use is to use masking tape on the floor, marking the 2 front corners before moving to what I think is the even better position. After a day when I decide the new position is worse then the previous, I just bring them back to the tape positions.

I also believe that speakers, within their room must have total symmetry. Easy to say, tuff to do. I use 2 small mirrors and put them on a straight front reference surface (if you have one) and find the spot I want to aim them to in the listening room. Most of the time, that spot is a few feet behind my easy chair. When I stand in that spot and can see the same image in both mirrors, I've got it dialed in. Yes, I use a tape measure to zero at least one corner of the speaker as a reference position, keeping both speakers at identical positions from the rear walls and the same for side walls. If rear wall distance is "A" distance, then I measure both speakers' reference corner and establish "A" distance for both. Then I measure out the distance from the side walls, call that distance "B". If you reference to the back outside corner of each speaker, you can use that corner as a pivot point, literally pivoting it (on a spike?) to the desired position where you think it's going to sound good. Put your mirror flat against that speaker. Go to the other speaker and toe-it in. Place the mirror in the same symmetrical postion as the other speaker. Go to your aiming spot and see if you have the same image in both mirrors. At least now, you can't blame symmetry for a lame sound.

Wayner

[zybar]

I agree George, looks like a very neat tool. Don't get me wrong, I'm not against using technology to help fine tune the speaker positions. I just know some people are going to get ultra fanatical about things like this and wear out their carpet or floor moving, moving and more moving. Let us know how it works out and how easy/difficult it was to use.

One trick that I use is to use masking tape on the floor, marking the 2 front corners before moving to what I think is the even better position. After a day when I decide the new position is worse then the previous, I just bring them back to the tape positions.

I also believe that speakers, within their room must have total symmetry. Easy to say, tuff to do. I use 2 small mirrors and put them on a straight front reference surface (if you have one) and find the spot I want to aim them to in the listening room. Most of the time, that spot is a few feet behind my easy chair. When I stand in that spot and can see the same image in both mirrors, I've got it dialed in. Yes, I use a tape measure to zero at least one corner of the speaker as a reference position, keeping both speakers at identical positions from the rear walls and the same for side walls. If rear wall distance is "A" distance, then I measure both speakers' reference corner and establish "A" distance for both. Then I measure out the distance from the side walls, call that distance "B". If you reference to the back outside corner of each speaker, you can use that corner as a pivot point, literally pivoting it (on a spike?) to the desired position where you think it's going to sound good. Put your mirror flat against that speaker. Go to the other speaker and toe-it in. Place the mirror in the same symmetrical postion as the other speaker. Go to your aiming spot and see if you have the same image in both mirrors. At least now, you can't blame symmetry for a lame sound.

Wayner

Some great tips Wayner.

To get my speakers positioned symmetrically, I use lasers.   aa

I tend to use mirrors for figuring out primary and secondary reflection points.  This helps me optimize room treatment placement.

George

[jbtrio]

I have the XTZ analyzer and, it is an invaluable tool. The built-in soundcard can be a little noisy, but for the money it is very good.
I especially like the Spectrogram. If you can get the low frequencies under 50ms your sound will be much clearer with less overhang.
Bass notes will be better defined, less boominess.

 I agree using your God given tools are important, but tools like this help show, how your room reacts to the changes you make!
Some people are blessed with good rooms, others have to work at it using room treatments, speaker placement, soft furniture, etc.
 
 I am a big fan of treating your room, so many people have mega-buck systems in bad rooms and, wonder why the sound isn't up to their expectations.Then they go on the equipment merry-go-round, problem is the room not the electronics.
 
 Having a good room is a platform for your system to perform at its best.

Joe

[fishinbob]

After two months I'm still messing with placement of my RTs. Initially they were placed 92" apart with 6 degrees toe in and then I saw Dennis' post and decided to bring them together a bit.
Now they sit 7 feet apart, and in my situation, the sound became more cohesive with a lot more going on in the middle of the soundstage. Since then I have been moving them towards the front wall bit by bit to get the right sound and noticed the changes especially in bass and mid-bass range. Last night I listened to some solo piano work and was detecting a rather diffuse sound especially when moving around a bit. Instead of making a minor placement change I decided to do a drastic toe in adjusment and cranked them around to 13 degrees and POW the piano became rock solid. I put on some other music and played with the toe a bit more and now they are toed at 11+ degrees with the seven foot spread with my listening position at 11'. The tweeters are aimed to cross 5' 5" behind my head. This configuation definately brought the 3D aspect on in spades. 
 I love playing with my toys.

[Big Red Machine]

I agree George, looks like a very neat tool. Don't get me wrong, I'm not against using technology to help fine tune the speaker positions. I just know some people are going to get ultra fanatical about things like this and wear out their carpet or floor moving, moving and more moving. Let us know how it works out and how easy/difficult it was to use.

One trick that I use is to use masking tape on the floor, marking the 2 front corners before moving to what I think is the even better position. After a day when I decide the new position is worse then the previous, I just bring them back to the tape positions.

I also believe that speakers, within their room must have total symmetry. Easy to say, tuff to do. I use 2 small mirrors and put them on a straight front reference surface (if you have one) and find the spot I want to aim them to in the listening room. Most of the time, that spot is a few feet behind my easy chair. When I stand in that spot and can see the same image in both mirrors, I've got it dialed in. Yes, I use a tape measure to zero at least one corner of the speaker as a reference position, keeping both speakers at identical positions from the rear walls and the same for side walls. If rear wall distance is "A" distance, then I measure both speakers' reference corner and establish "A" distance for both. Then I measure out the distance from the side walls, call that distance "B". If you reference to the back outside corner of each speaker, you can use that corner as a pivot point, literally pivoting it (on a spike?) to the desired position where you think it's going to sound good. Put your mirror flat against that speaker. Go to the other speaker and toe-it in. Place the mirror in the same symmetrical postion as the other speaker. Go to your aiming spot and see if you have the same image in both mirrors. At least now, you can't blame symmetry for a lame sound.

Wayner

Bryan recommended moving the center of the listening seat 6 inches to one or the other sides and to be at approx 62% back from the front wall (seat).  Seems to work pretty darn well.  Sp symetrical, but shifted so to speak.  I eyeball the toe in amount but will try a laser for kicks to see how good my eye was.

[zybar]

I have the XTZ analyzer and, it is an invaluable tool. The built-in soundcard can be a little noisy, but for the money it is very good.
I especially like the Spectrogram. If you can get the low frequencies under 50ms your sound will be much clearer with less overhang.
Bass notes will be better defined, less boominess.

 I agree using your God given tools are important, but tools like this help show, how your room reacts to the changes you make!
Some people are blessed with good rooms, others have to work at it using room treatments, speaker placement, soft furniture, etc.
 
 I am a big fan of treating your room, so many people have mega-buck systems in bad rooms and, wonder why the sound isn't up to their expectations.Then they go on the equipment merry-go-round, problem is the room not the electronics.
 
 Having a good room is a platform for your system to perform at its best.

Joe

My XTZ kit arrived and I hope to try it tonight.

George

[ted_b]

George (and other XTZ users),
I'm looking forward to your report(s).  I have several (14) Realtrap products in my room, along with a dozen ASC half rounds on the sloped ceiling.  In anticipation of the repainting, and riser install in back third of room, I've taken down the ASC half rounds (am gonna sell them cuz they're wrong color,etc.) and am very interested in thinking about using an XTZ  for hearing AND seeing the differences as I add or subtract room treatments during this process.

[zybar]

George (and other XTZ users),
I'm looking forward to your report(s).  I have several (14) Realtrap products in my room, along with a dozen ASC half rounds on the sloped ceiling.  In anticipation of the repainting, and riser install in back third of room, I've taken down the ASC half rounds (am gonna sell them cuz they're wrong color,etc.) and am very interested in thinking about using an XTZ  for hearing AND seeing the differences as I add or subtract room treatments during this process.

Ted,

This is exactly what I plan to do with all of my RealTraps panels.

I did this in a very small fashion last weekend when using the SMS-1 to dial in the bass on my 5A's.  My friend and I clearly saw that moving just a single RealTraps panel could impact the readings.

George

[oneinthepipe]

George (and other XTZ users),
I'm looking forward to your report(s).  I have several (14) Realtrap products in my room, along with a dozen ASC half rounds on the sloped ceiling.  In anticipation of the repainting, and riser install in back third of room, I've taken down the ASC half rounds (am gonna sell them cuz they're wrong color,etc.) and am very interested in thinking about using an XTZ  for hearing AND seeing the differences as I add or subtract room treatments during this process.

Ted,

This is exactly what I plan to do with all of my RealTraps panels.

I did this in a very small fashion last weekend when using the SMS-1 to dial in the bass on my 5A's.  My friend and I clearly saw that moving just a single RealTraps panel could impact the readings.

George

I am eager to read about your experience, too, George.  My traps/panels are from acoustimac, and Sal, the owner, stated, when I was discussing the panels' placements with him, "Isn't it funny how moving one panel can make so much difference?"  I wouldn't describe it as funny, but it certainly is interesting.  I found the most noticeable difference, without the use of any metering device, with the location of the panels on the ceiling, where there is less coverage per square foot than on the walls.