Speaker Tilt Back benefits?


Hi all!
I need to purchase new spikes for my Audio Physic Virgo speakers (they have attached bars on the bottom front and back to stabilize the speaker and attach the spikes to), and it has been recommended to me that I purchase taller spikes for the front and smaller for the back in order to create a tilt back effect, which, I guess, is already built into the newer Mk III version of these speakers . However, I can't find much info on why this would be a good thing.
Thoughts?
Thx,
james
Convert?fit=crop&h=128&rotate=exif&w=128slaw3
The idea is that tilting the speaker to the rear moves the tweeter a bit further from your ears, so their output (in theory) arrives at your ears at the same time as the output from the other drivers in the speaker. The tweeter cone has much less mass than the other drivers, so they propogate sound faster than mid-range or woofer drivers.

When sound waves arrive simultaneously at the listener's ear, it is referred to as time alignment (which is a feature of certain speaker designs such as Vandersteen). Time alignment, however, is also somewhat dependent on the distance from the speaker to the listener. Ideally, time aligned speakers should be at least 8-10 feet from the listener.
The idea is that tilting the speaker to the rear moves the tweeter a bit further from your ears, so their output (in theory) arrives at your ears at the same time as the output from the other drivers in the speaker.
because the tweeter isn't as deep as the rest of the drivers, and if they are all mounted on the front of the cabinet then the tweeter is actually a little closer than the other drivers.

All sound frequencies travel at the same speed. It is not true that
The tweeter cone has much less mass than the other drivers, so they propogate sound faster than mid-range or woofer drivers.
Tilting them back changes the relative position of your ears to the drivers. Also either takes or puts your ears on the drivers' combined axis. If you seem to be sitting too low or too high (for tonal response relative to the drivers) then tilting can help this.
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>The tweeter cone has much less mass than the other drivers, so they propogate sound faster than mid-range or woofer drivers.

While driver mass effects efficiency (that whole force = mass * acceleration thing), it has nothing to do with how soon the sound waves from a driver will reach you.

The other drivers are deeper than a tweeter so their acoustic centers are logically farther back.

Angling the speaker puts you closer to on-axis which will increase tweeter output at high frequencies. It will put you closer to the zero delay plane where output will be maximal for a speaker with Linkwitz Riley even order cross-overs or where odd-order cross-overs sum flat (you get a 3dB peak off-axis).
Slaw3.I have a pair of NHT3.3 speakers which I have had for eight years.My biggest complaint regarding these was I always felt the soundstage to be to low in height .A year ago I put long screws thru my front supports into my spikes. Then I experimented tilting the speakers back. The screws I used were 5 inches long and after about two weeks of trial I found at 1.33 inches in lift I got the soundstage to lift in height about 18 inches any higher and I lost depth to the sound stage. After I was happy with the height I took a inch and a half dowel cut it to length drilled a hole thru the length painted them black cut the screws to the correct length. They look like they came this way.My outriggers or bars as you call them are threaded so for less than a dollar you can experement for yourself. Sorry I waited so long before I tryed this.
Tilting up or down, toeing in or out, moving closer or further apart, back or forth, etc., will affect tonal balance - and equipment and room acoustics will have a big effect. Whether there's a benefit depends on your preference. Whoever recommended tilting back probably noticed a positive effect; you may or may not. Another way to look at it is: if Audio Physic thought it would be a benefit, they would have incorporated it.

As far as titling back the speaker to "align" the drivers in order to increase the distance of the tweeter to that of the lower driver in an effort to get the sound waves to the ear at the same time is probably not going to be of any significance for the Virgo. The drivers are so close together that it may be a futile exercise - moving your head up or down a half inch will have practically the same effect.

Nothing wrong in experimenting, though.
Thanks, y'all!
I'm buying new spikes because the old set was lost in a move, and I was using inferior and cheap spikes - had one of those "aha" moments the other day and realized new spikes would probably improve the sound quite a bit. I've just tried just tilting them back a little using some mouse pads under the front outriggers, and I liked the sound; seemed to be a little more airy high end and better rhythm to the music. Could be some of that time align theory at work, or just a better balance for my room as GS5556 suggests. I'll try it with the spikes when they arrive and report back!
jSlaw
The Mapleshade speaker stands utilize a tilt, and the stands are really a misnomer as they are a few inches off the floor. When used with the Reference 3A de Capo i's this improved the bass response and soundstage and the sound just got better from these speakers. L'wood
Some speakers have tweeters below the woofer, and some (MTM) have the tweeter in between two woofers.

Tilting speakers back reduces the LF bounce off the floor. It also discourages people from setting drink glasses down on the top.
What sounds better will largely depend on your room acoustics, listening position and the vertical dispersion pattern of the speaker. There is no "rule of thumb" for this....just experiment. If a slight tilt makes a significant difference then this would indicate a problem somewhere....either room acoustics or the speaker. In this case, you may want to try to fix the root cause....
This may sound crazy, but I've got the Virgo II's little brother, the Spark. I have used a different approach in my room. I listen about 6ft from ear to midwoof, and 8ft apart, so I'm in the nearfield. Anyway, the soundstage depth is so good-it starts at the plane of the mains and goes back from there. I actually tip the speakers forward, not back and it seems to increase the height of the stage. Obviously YMMV, but I swear I've seen this in pics under member systems where a fellow had the Virgo II's tipped forward, so I have a feeling I'm not the only one doing this. Hope this is some help, don't mean to confuse, just explaining my results. -Fish