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description: Audio advice and discussions with audiophiles and professionals. Free discussion forums, open to all and frequented by industry experts. Ask questions and get advice on stereos, speakers, hi-end amplifiers, pre-amps, home theater, tube hi-fi, turntables, vinyl, tweaks, music, films, video, DVDs and more.
items: Imaging, placement and orientation
items: Re: Imaging, placement and orientation

Imaging, placement and orientation
type: item
description: We've discussed uniform directivity and its benefits many times here. We've also talked about the reasons why the imaging of the π cornerhorn is good throughout a large listening area, because of the combination of its uniform directivity and the requisite orientation having its forward axis toed-in 45°. This arrangement can be employed in other speakers having uniform directivity too, and it is recommended for the three π and four π speakers as well as the cornerhorns. Making speakers "disappear" Pi horn design philosophies Corner Horn positioning "Sweet Spot" for listening Recommended toe in This approach has gained popularity in the last few years. For a long time, we were the only ones doing it. Most directional sources that imaged well needed a pinpoint listening spot, and movement of just a few inches ruined it. The biggest examples that come to mind are planar speakers, which image like crazy if you don't move an inch. Most horns work this way too, especially the tractrix round horns. For historical perspective, consider that Klipschorns are designed for corner placement and have 45° toe-in. Of course, they use exponential midrange and tweeter horns that beam at HF so they do not provide uniform directivity. But the fact they are positioned in corners sets the beamwidth at least at the low end, making them more uniform than many modern loudspeaker, even some that are designed to be "constant directivity waveguides". So by using the crossed-axes configuration, stereo balance is quite good through an area near the point where the axes cross. Since the horns used don't provide constant beamwidth, the "sweet spot" isn't as large as if the horns were CD, but it is still works over a limited area. In fact, Paul Klipsch describes the same method of aggresive toe-in in his "Dope from Hope" series, so while unusual, it isn't new. But what is somewhat new, and what makes this configuration a significant improvement, is combining the crossed-axis toe-in with constant di…
creator: Wayne Parham
date: 2009-01-02T21:31:12-00:00

Re: Imaging, placement and orientation
type: item
description: I can attest to this. I have been using my Stage 4's temporarily for L & R speakers in a home theater set up. Set up as you recommend(and with no center channel speaker) the image is locked in at the TV set. I can slide from side to side with little or no effect on the stability of the image. The phantom center image is now so good that for the first time I am questioning the need for center channel speaker. Given this plus their dynamic range I think you would be hard pressed to find many speakers that would work better for home theater applications. LAL
creator: LAL
date: 2009-01-03T21:14:36-00:00

Re: Imaging, placement and orientation
type: item
description: While an interesting read, this does not address the vertical aspect of the sound reaching a person. Say I am standing next to a person sitting down. The person sitting down is in the optimal position to listen to speakers placed at a 45 degree angle. I am standing next to that person, perhaps 2-3 feet above their ear level. I am benefitting less from the sound than they are. I experienced this with my 2 Pi Towers the other day as my wife was seated in the optimal position while I stood next to her. Not that what I heard was unpleasant, but it was far from optimal.
creator: breakfastchef
date: 2009-01-06T01:38:38-00:00

Re: Imaging, placement and orientation
type: item
description: That's very true. The one π and two π models do not provide constant directivity like the three π, four π and π cornerhorn models do. The one π and two π speakers are direct radiators with fairly simple crossover networks. They're great for on-axis listening, but cannot provide uniform directivity like the horn models do. Best performance from the one π and two π models is best realized straight on-axis with the midwoofer. That's what they are designed for. The three π, four π and π cornerhorn models are a different breed though. Each is designed to provide uniform directivity throughout a 90°x40° pattern. Not only are they designed for spectral balance along a 90° horizontal arc, but also up and down through a 40° vertical arc. Beyond that, HF output is sharply reduced, which is useful for limiting ceiling slap. The improved vertical pattern sets these models apart from similar speakers from other manufacturers, where attention is paid almost solely on the performance along the horizontal plane. Our speakers are designed for superior spectral balance within the pattern in both horizontal and vertical planes. Matching directivity in the vertical and the horizontal planes <br(.*)
creator: Wayne Parham
date: 2009-01-06T02:35:25-00:00

Re: Imaging, placement and orientation
type: item
description: Well, I suppose a 4 Pi may be in my future with approval from my 'roommate'.
creator: breakfastchef
date: 2009-01-06T04:04:03-00:00

Re: Imaging, placement and orientation
type: item
description: That's what I have in my living room. Four π speakers with JBL 2226 woofers and B&C DE250 compression drivers. I also have a pair of three π subs, to increase bass extension and even more importantly, to smooth room modes. In my office I have seven π cornerhorns and in my bedroom I have two π towers. I spend a great deal of time in each room.
creator: Wayne Parham
date: 2009-01-06T04:34:48-00:00

Re: Imaging, placement and orientation
type: item
description: if you wanna get the most out of your nice-looking amps... The 4Pi's a 'sneaky' large cab- bigger than it looks, especially if you finish 'em dark. Not as large as a lot of hi-eff models out there.
creator: Matts
date: 2009-01-06T04:55:37-00:00