Back on track... more basics questions

[pixelthis]

OF course you want to point those tweeters in your general direction to get some of that great B&W imaging.
I've done some police work (no white collar stuff so dont worry) and you would be surprized to see hpw much changing your source object changes how the destination turns out. Raising your CC with a few coins (or lowering) can change the sweet spot
by several feet.
And if anybody paid 19.95 for that airconditioner foam, you got ripped, somebody cut it to order and is making a fortune

[musicman1999]

The reason the center has to be even with the shelf,or stand that it rests on is to avoid reflections from that shelf or stand that it rests on.Setting the levels can't compensate for reflections of sound waves.There is far more to proper set up than setting the levels,proper placement is key to building a good soundstage.

bill

[Rich-n-Texas]

It's not real easy to tell from this picture the lip that overhangs the TV stand's compartments, and I've since eliminated the glass speaker stand because it wouldn't allow me to point the CC, but my concern is getting the tweeter extended out past the decorative curved molding on the top shelf where the TV sits. The MoPADS were only $25. shipped, and if they don't work out I'll use them for one the rear surrounds and buy another set for the other one. I realize that ideally the CC should be even with the screen, which isn't possible in my case, but what I read here tells me that the face of the speaker cannot have any obstacles or reflection surfaces nearby, so that's why I'm trying to angle it and project it out from the opening in the TV stand. The fact that the MoPADS will raise it 1.25" won't be a concern because the glass stand used previously raised it the same distance and there was no problem with clearance then. The MoPADS will provide two benefits: point the CC at my ears (crippled though they may be) and de-couple it from the shelf.

[kexodusc]

The reason the center has to be even with the shelf,or stand that it rests on is to avoid reflections from that shelf or stand that it rests on.Setting the levels can't compensate for reflections of sound waves.There is far more to proper set up than setting the levels,proper placement is key to building a good soundstage.

bill

This is good advice. Despite what some would believe, frequencies below 1000 Hz or so will "wrap" around the speaker. They don't just shoot straight forward.

The bad part about the reflections caused when the speaker isn't even, is that they lie in the mid-range,where our ears are most sensitive to such interference. You don't want reflections smearing the sound, especially if they're easily avoidable.

With center channels, most designs assume the speaker will have close proximity to a TV screen or wall as well, sort of a built in baffle step compensation for step-loss.

[Rich-n-Texas]

Here are a couple of closeups of the CC speaker in the TV stand:

The pixelsplease prefered method of CC speaker jacking:



And a view showing how far out it has to project to clear the top shelf overhang:



The MoPADS are on their way, and if it turns out they're not rigid enough to support the weight of the speaker when I move it forward of the shelf, I've got an idea to tach spray a couple of paint stirring sticks to the bottoms of the pads, which I think will firm them up.

[pixelthis]

Here are a couple of closeups of the CC speaker in the TV stand:

The pixelsplease prefered method of CC speaker jacking:



And a view showing how far out it has to project to clear the top shelf overhang:



The MoPADS are on their way, and if it turns out they're not rigid enough to support the weight of the speaker when I move it forward of the shelf, I've got an idea to tach spray a couple of paint stirring sticks to the bottoms of the pads, which I think will firm them up.

I have a solution, rich in you're own mind.
That speaker is totally inappropriate for that spot, SO just send it to me and I'll send ya my
300$ klipsh center, should be a perfect fit!

[pixelthis]

Put a shelf over the tv and put a few coins in BACK of the center to point it down
OR even better you could toss out that big bulky set like the rest of america is doing
and get you a nice LCD, hang it on the wall, and put your CC where your TV is now

[L.J.]

The bad part about the reflections caused when the speaker isn't even, is that they lie in the mid-range,where our ears are most sensitive to such interference. You don't want reflections smearing the sound, especially if they're easily avoidable.

Kex, are you saying that angleing your CC toward the listening position is a bad thing? I know that the ideal location is at ear level, but this is almost impossible for alot people because this is exactly where the TV is sitting. My CC sits 3ft above my mains but there isn't much I can do about that.

[kexodusc]

Kex, are you saying that angleing your CC toward the listening position is a bad thing? I know that the ideal location is at ear level, but this is almost impossible for alot people because this is exactly where the TV is sitting. My CC sits 3ft above my mains but there isn't much I can do about that.

No no no...not at all. Angling helps too.
Just wanted to emphasize that when centers are placed on shelves or in big entertainment unit spaces, try and have it flush with a large broad side (ie, tv screen, front of unit, etc). Personally, I think this would be more important than the degree of tilt unless you're really far off axis.

When it comes to angling, I try and be a bit more pragmatic too. My center is probably a good foot above my ears. I tilt it a bit, but there might be 1/4 inch or less of lift applied at the back to tilt the front downward.

Most speakers have decent off-axis radiating patters usually up to 15 degrees or so.

The degree of off axis responses doesn't make them any better sounding necessarily, but it is useful for center channels. If your sitting 10 feet from a center channel, 15 degrees corresponds to about 2 and a half feet or so vertical leeway, that is your ears can be 2.5 feet or so off axis with minimal change in response... That's a good variance. At 8 feet distance, it's a little over 2 feet. Even if you play it safe and cut the 15 degrees requirement in half, you've still got quite a bit of vertical allowance.

MTM alignments (midwoofer, tweeter, midwoofer) typical of most centers these days have pretty good off axis response on the vertical axis. If you're really sensitive to the high frequencies, and your tweeter doesn't have great dispersion, the above won't really hold true and you might notice the higher treble decreasing a bit, but it's a good place to start. The mids and lower are fairly safe still though.

All that to say that tilting/angling the speakers doesn't always make a big difference, or perhaps that we don't need to tilt the speaker so that it's pointing perfectly at your head...we've got some wiggle room. Mine still shoots well above my head. If I didn't tilt it at all, I could notice some loss of brightness.
I prefer the slight tilt to a more aggressive tilt I had tried because I couldn't hear any difference and I was worried it would fall off my set (my wife's cat has a bad habit of jumping around that area).

Think about it - you've probably toyed with the toe-in on your mains. Ever own a pair of speakers that needed large differences in the amount of toe in before you noticed a difference in sound? Same principle - the off axis response probably didn't change much for the first few degrees...

[L.J.]

No no no...not at all. Angling helps too.
Just wanted to emphasize that when centers are placed on shelves or in big entertainment unit spaces, try and have it flush with a large broad side (ie, tv screen, front of unit, etc). Personally, I think this would be more important than the degree of tilt unless you're really far off axis.

When it comes to angling, I try and be a bit more pragmatic too. My center is probably a good foot above my ears. I tilt it a bit, but there might be 1/4 inch or less of lift applied at the back to tilt the front downward.

Most speakers have decent off-axis radiating patters usually up to 15 degrees or so.

The degree of off axis responses doesn't make them any better sounding necessarily, but it is useful for center channels. If your sitting 10 feet from a center channel, 15 degrees corresponds to about 2 and a half feet or so vertical leeway, that is your ears can be 2.5 feet or so off axis with minimal change in response... That's a good variance. At 8 feet distance, it's a little over 2 feet. Even if you play it safe and cut the 15 degrees requirement in half, you've still got quite a bit of vertical allowance.

MTM alignments (midwoofer, tweeter, midwoofer) typical of most centers these days have pretty good off axis response on the vertical axis. If you're really sensitive to the high frequencies, and your tweeter doesn't have great dispersion, the above won't really hold true and you might notice the higher treble decreasing a bit, but it's a good place to start. The mids and lower are fairly safe still though.

All that to say that tilting/angling the speakers doesn't always make a big difference, or perhaps that we don't need to tilt the speaker so that it's pointing perfectly at your head...we've got some wiggle room. Mine still shoots well above my head. If I didn't tilt it at all, I could notice some loss of brightness.
I prefer the slight tilt to a more aggressive tilt I had tried because I couldn't hear any difference and I was worried it would fall off my set (my wife's cat has a bad habit of jumping around that area).

Think about it - you've probably toyed with the toe-in on your mains. Ever own a pair of speakers that needed large differences in the amount of toe in before you noticed a difference in sound? Same principle - the off axis response probably didn't change much for the first few degrees...

Makes sense. As always thanks for taking the time.

[L.J.]

OF course you want to point those tweeters in your general direction to get some of that great B&W imaging.
I've done some police work (no white collar stuff so dont worry) and you would be surprized to see hpw much changing your source object changes how the destination turns out. Raising your CC with a few coins (or lowering) can change the sweet spot
by several feet.
And if anybody paid 19.95 for that airconditioner foam, you got ripped, somebody cut it to order and is making a fortune

I'm sorry but spending $19.95 on a product that meets your needs is not getting ripped. My CC sits 3 ft above my mains. A few coins weren't gonna cut it. I have my CC angled exactly how I want it now and the decoupling is a added benefit. They look nice too. A thumbs up from wifee is always a good thing

[Rich-n-Texas]

Yeah. What he said!

[pixelthis]

Where to begin...
FIRST OFF what "reflections" are you talking about? Bass is omnidirectional anyway
and most will come out of your sub, the mid and upper freks will clear a few inches of shelf without hitting it at all, this is basically a non problem.
And even a slightchange of the direction of a tweeter can change the sweet spot since they are directional to a great degree, but proper setting of levels will compensate
for misaligned speakers somewhat.
As for paying 20 bucks or so for something you can do for free... Well, its your money but Personally I think you'd get a lot more sastifaction just mailing it to me.
I'll send you some shims to put under your speaker and we'll both be better off.
I'll even wrap em in airconditioner foam for ya.
My neighbors got a window unit and is going outta town for a few days....