Obsessive about SDA Alignment

inspiredsports

I've been working a long time toward reaching SDA imaging nirvana and wanted to share a few hints I've learned along the way that may save others some time.

As I've tweaked and upgraded, my system has become far more revealing. It's now basically to the point where the focus of a specific voice or instrument is essentially holographic. It's position can be heard and visualized by height, direction and and distance from my listening position.

At one point a few months back the center image seemed to be originating from a point left of center, and higher than the height of the tweeters. I started checking connections, balance controls, etc. and found nothing wrong.

I remembered it had been a while since I checked the "alignment" of the front plane of my speakers and found them to be a bit out of whack, and I've even acquired an inexpensive laser level since then to improve accuracy.

I first level the speakers so the are 90 degrees perpendicular to the floor.

I then shoot a laser level beam from the left wall across to the right and get both speakers exactly parallel to the wall and the exactly the same distance from it by nudging the outside edges of each speaker just into the beam.

You can get nearly holographic results with a good source, clean signal path and precise speaker alignment!

headrott

Good advice. Although I'm not "obsessed" about alignment, that is the point of having SDAs correct (having the "stereo sweet spot)?

F1nut

You just realized that?

inspiredsports

F1nut wrote: »

You just realized that?

To a certain point, but my system never had the resolution before to expose problems when something was tilted just a degree or two.

Dawgfish

It's funny I was going to post a thread about how super picky SDAs were to placement yesterday but was short on time. A couple of days ago, I was swapping amps out in my two channel rig. I had to move my right SDA-1C away from my rack to gain access to the rear of the amp and disconnect the cables and speaker wires. I swapped out the amp and put everything back to their original spots, or so I thought. When I powered the system up, things just didn't sound right. The right channel just sounded muffled and not clear at all. I immediately pulled the rack back out and started checking speaker wire polarity and connections, rca connections both at the amp and pre, etc. I couldn't find anything wrong. I pushed the rack back in and listened again. It still sounded the same. I was about to go insane thinking maybe the new amp was bad when I noticed the right speaker was out about 9-10 inches from the back wall and it was not parellel to the wall. I pushed it back to 6 inches from the wall like the left speaker and aligned it to be parrellel with the wall. Voila, SDA nirvana was back! I just couldn't believe how much of a difference the placement made. It was like going from having the right channel nearly completely out to having it right there in your face and sounding wonderful.

Thanks on the tip on having the SDAs completely level. I was not aware of that one and will be checking it tonight. I am now aware of just how sensitive these babies are to placement. Where's my level and tape measure?

Steve

hearingimpared

After setting up my 1.2TLs for the perfect sweet spot, I used a bubble level to make sure the speakers themselves were perfectly level.

F1nut

inspiredsports wrote: »

To a certain point, but my system never had the resolution before to expose problems when something was tilted just a degree or two.

I forgot the

It's important info, thanks for bringing it up.

Fongolio

My listening position/sweetspot is on one side of a Lazy Boy recliner couch. My floors are laminate and the couch is sitting on small carpet pieces at the contact points. Problem is the couch moves around quite a bit with normal use and puts my sweetspot out. I've marked in pencil on the floor exactly where the couch should line up for the perfect listening position with my SDA-1c's. I confirm or adjust alignment of the speakers once a month or so. When all is dialed in correctly they just sound magnificant.

Last night I was listening to Mark Knopfler's Golden Heart on cd and it was truly awesome how good these speakers sound. An excellent early Mark Knopfler solo album that I'd never heard before with great SDA effects. Highly recommended.

heiney9

Norah has been floating dead center, holographically in front of me for about 2 years. If I close my eyes I can imagine her sitting at the piano about 4 feet in front of me. I have the strongest center image and instrument placement I've ever had in a system with my SDA's.

I am exactly equidistant from the speakers in an equallateral triangle, meaning my head is exactly the same distance from the speakers as the speakers are seperated. I have worn a slight indentation in my couch where the exact sweet spot is. I sit there constantly.

Welcome to the SDA experience.

H9

EDIT: I'll add that I have measured the distance from the wall at 3 points on my 1C's, top; middle bottom so I know they are exactly parallel and 10" out from the wall they are place on.

vc69

I may be missing something here, but aren't all good systems supposed to have a holographic image? I mean... I get a really nice 3D stage with my LS's.;)

TNRabbit

Speaker alignment & room placement are probably the two MOST overlooked essentials in getting the most out of your system~

hearingimpared

vc69 wrote: »

I may be missing something here, but aren't all good systems supposed to have a holographic image? I mean... I get a really nice 3D stage with my LS's.;)

You are missing something if you haven't had your ears on SDAs.:)

vc69

hearingimpared wrote: »

You are missing something if you haven't had your ears on SDAs.:)

One of these days.

DarqueKnight

vc69 wrote: »

I may be missing something here...

Yes. It's one of those things you don't understand until you experience it. However, that is not to say that you will like it once you hear it. Some people prefer the sound stage rendering of conventional speakers. For some people, SDA has to grow on them.

vc69 wrote: »

...aren't all good systems supposed to have a holographic image?

Stereophonic yes. Holographic no.

Remember, all good cars are supposed to have a good breaking system, but there are (sometimes drastic) differences.;)

vc69 wrote: »

I get a really nice 3D stage with my LS's.;)

No doubt. See the car analogy above.

Conradicles

inspiredsports wrote: »

I then shoot a laser level beam from the left wall across to the right and get both speakers exactly parallel to the wall and the exactly the same distance from it by nudging the outside edges of each speaker just into the beam.

Sweet. I use a tape measure, but it has flaws. May try this just to make sure I am in the "Laser Sweet Spot". The bubble level has always been my friend as well!;)

Currently I have been working on DIY room treatments for my Man Cave. It sure needed it.

SDA's sound like great headphones when set-up properly.:cool:

headrott

Since viewing this thread and reading another, I bought a laser alignment with a tripod and bubble level. I can say that I have become a little obsessive about the aligment of the 3.1TLs.;)

However, the SDA effect has improved quite a bit by using the laser/level tool. I recommend everyone do this to get the maximum SDA effect.

Greg

mewisemagic

DarqueKnight wrote: »

Yes. It's one of those things you don't understand until you experience it. However, that is not to say that you will like it once you hear it. Some people prefer the sound stage rendering of conventional speakers. For some people, SDA has to grow on them.



Stereophonic yes. Holographic no.

Remember, all good cars are supposed to have a good breaking system, but there are (sometimes drastic) differences.;)



No doubt. See the car analogy above.

hey, is that crack about toyota's Braking system:p

dbaldus

heiney9 wrote: »

I am exactly equidistant from the speakers in an equallateral triangle, meaning my head is exactly the same distance from the speakers as the speakers are seperated. I have worn a slight indentation in my couch where the exact sweet spot is. I sit there constantly.

I'm trying to get my original SRS's set up properly and wanted to try out this equilateral triangle idea. When you are referring to the distance between the speakers, are you talking about inside cabinet edge to inside cabinet edge or tweeter to tweeter?

If you think it seems like it wouldn't be a big deal, remember that this would make a difference of nearly two feet on the big boys!

Thanks!

inspiredsports

dbaldus wrote: »

I'm trying to get my original SRS's set up properly and wanted to try out this equilateral triangle idea. When you are referring to the distance between the speakers, are you talking about inside cabinet edge to inside cabinet edge or tweeter to tweeter?

If you think it seems like it wouldn't be a big deal, remember that this would make a difference of nearly two feet on the big boys!

Thanks!

Others may have different ideas. I've always used tweeter to tweeter for "sweet spot" calculations, the outer edge of the cabinet for distance from side wall measurements, and distance from back of cabinets for distance to back wall measurement. Clicking on the thumbnail in post #1 will open a large, detailed image.

headrott

I agree with insipredsports, I do tweeter to tweeter for the distances. I don't know if this is absolutley correct or not but it seems to work well to my ears.

Greg

tojohndillonesq

Really great speakers do provide great holographic imaging... in fact, an average pair of Magnapans can do it. Mine had a spot about the size of a basketball. Great that they had one at all, but ridiculous that it was a one person experience. It was like a Magic show. Stand behing my chair and listen; now just lean forward and lower your head. Suddenly the volume level would apparently double and the stage would just spead out in front of you. Fun to show off, but not really a great system. Plus they were very dry sounding, light on bass, hard to amplify etc, so I traded them.

1.2s in the right room and right set up will give you the stage experience for a relatively large listening area. Certainly a couch width, and maybe a second row, sitting or standing. Not to mention that they deliver a huge range of of sound, from below human hearing to above it. I highly recommend Floyd's Dark Side of the Moon. WOW. Speakers 60* wide from my vantage, stage 120* wide. Wow. Wow. The best setup I have ever listened to, bar none, $100K systems included.

I have seen them set up so they do not deliver this, and it is like seeing a guy living over a gold mine but refusing to dig. Even sloppily placed they do their best to disappear, but they won't give you the front to back imaging, or the stage that is wider than they are.

So yes, I am a true believer. They are like the magic show where you open the curtain to see how the trick was done and find out it was no trick; just real magic.

cnh

+1, SDAs require a lot of tweaking...even if you follow the Polk directions....different rooms have different effects. Equipment is also a factor. I have yet to find a GOOD room in my house that shows off the full potential of the 'effect'. And, as everyone here knows, NOT all recordings are 'equal' there! The problem is I live in an old house that has narrow rooms...so very few have the minimal width for SDAs...............let's say two SDAs are about 3 ft in width....you need another 3 ft x 2 from the walls (6 ft) and then you need a minimum of 4 ft between the speakers--so 9 ft + 4 ft = a 13 ft....minimum? The way my house is set up, there are two rooms that LONG. One is the AV room so no SDAs in there and the AV is on the 11.5' wall--in any case--so NO GO there? The basement is 10 x 21 x 6.8 so if you position the SDAs on the 21 foot wall and your couch is 3 ft out....the SDAs are 1.5' out from the wall at their front and that means your couch has 5.5's between it and the front of the speakers? Minimal at BEST! Because the bass likes to bounce off the very SHORT distance it has to travel to the back wall and echo around the room? Not enough room for the BASS waves.

But I get by in any case.

cnh

tojohndillonesq

Really great speakers do provide great holographic imaging... in fact, an average pair of Magnapans can do it. Mine had a spot about the size of a basketball. Great that they had one at all, but ridiculous that it was a one person experience. It was like a Magic show. Stand behing my chair and listen; now just lean forward. Suddenly the volume level would apparently double and the stage would just spead out in front of you. Fun to show off, but not really a great system. Plus they were very dry sounding, light on bass, hard to amplify etc, so I traded them.

1.2s in the right room and right set up will give you the stage experience for a relatively large listening area. Certainly a couch width, and maybe a second row, sitting or standing. Not to mention that they deliver a huge range of of sound, from below human hearing to above it. I highly recommend Floyd's Dark Side of the Moon. WOW. Speakers 60* wide from my vantage, stage 120* wide. Wow. Wow. The best setup I have ever listened to, bar none, $100K systems included.


I have seen them set up so they do not deliver this, and it is like seeing a guy living over a gold mine but refusing to dig. Even sloppily placed they do their best to disappear, but they can give you the front to back imaging, or the stage that is wider than they are.

So yes, I am a true believer. They are like the magic show where you open the curtain to see how the trick was done and find out it was no trick; just real magic.

hearingimpared

inspiredsports wrote: »

Others may have different ideas. I've always used tweeter to tweeter for "sweet spot" calculations, the outer edge of the cabinet for distance from side wall measurements, and distance from back of cabinets for distance to back wall measurement. Clicking on the thumbnail in post #1 will open a large, detailed image.

According to the manual for 1.2TLs, 2.3TL and CRS+s the distance between speakers is calculated from the middle of each speaker which in the SDAs listed in this sentence are the tweeters.

codyc1ark

Did this with my CRS's today and... WOW! I didn't realize that they we're so far toe'd in/out, really brought them to life. More bass, more mids, sounds great all around.

thejck

Lasareath wrote: »

I'm planning on having bolts set in concrete in my basement and then I'm going to screw the 1.2TL's to those bolts so that they will be in perfect alignment and cannot ever move!

It should improve the bass response as well

Man talk about home improvement..The next buyers of your house better pay a premium for those speakers that "come" with the house.

thejck

At what height should your ears be for the 1.2's. Which row of tweeters should they align with?

Also I know its recommended that we have 3 feet to the side walls from the speakers with no obstructions. I need to have a pair or rti12's for my HT setup on the same plane as the sda's. You can see my setup in the following posts.
http://www.polkaudio.com/forums/showpost.php?p=1407644&postcount=11
http://www.polkaudio.com/forums/showpost.php?p=1407646&postcount=12

Should I move the sda's out so they are 3 feet from the wall and then move the rti12's on the inside of the sda's? The total length of the wall is 20 feet.

hearingimpared

thejck wrote: »

At what height should your ears be for the 1.2's. Which row of tweeters should they align with?

Also I know its recommended that we have 3 feet to the side walls from the speakers with no obstructions. I need to have a pair or rti12's for my HT setup on the same plane as the sda's. You can see my setup in the following posts.
http://www.polkaudio.com/forums/showpost.php?p=1407644&postcount=11
http://www.polkaudio.com/forums/showpost.php?p=1407646&postcount=12

Should I move the sda's out so they are 3 feet from the wall and then move the rti12's on the inside of the sda's? The total length of the wall is 20 feet.

I sit on a phone book to raise my ear level to the third from the top tweeter in that that tweeter is full range (for highs) and the loudest one. I didn't looke at your pics but from you description, I would do just that.

IMHO you'll get maximum SDA effect and the RTI 12s shouldn't interfere with the center imaging. I have a four tier VTI rack in between my 1.2 TLs with the top tier having my TT and top loading CDP and it being up to the bottom tweeter and it has no effect on the center fill of imaging.

thejck

Ok,
I got some pics. of the left side with the rti12 on the inside and of the right side with the rti12 on the outside. As you can also see there is no side wall on the right side. There is 3 feet between the left 1.2 and the wall. I plan on bringing the sda away from the wall so it sits even with the front of the rti12. That will be about a foot away from the back wall.

Any thoughts?

hearingimpared

Okay, with that huge entertainment center, you need the SDA's bezel to be at least 2" forwad of the entertainment center because it is so large to get the. full SDA effect. center fill and center imaging.

Check the pdf manual I sent you it will describe how and why this needs to be done.

thejck

The entertainment center is inset into the wall. So all the speakers have their backends in front of the entertainment center.