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dean_martin
08-31-2004, 07:07 AM
A couple of months ago I ran across an old Sound & Vision mag that featured a speaker listening session with members of Phish. They were listening to 3 pairs of floorstanders from Energy, JBL and NHT. The Energy pair was consistently the favorite - no this wasn't a DBT and I realize that some folks here can't stand celebrity advice on audio gear. But, this is just the set up for my inquiry. The Energy entry was from their former highend range the Audissey. It came in about three different sizes, but its unique characteristic was its 2 tweeters. The one firing to the rear was supposed to provide more "air and space." Has anyone heard this speaker? When the Verita line replaced the Audissey, did Energy go to a single tweeter direct approach? What manufacturers use the 2 tweeter or omnidirectional design for mains and which ones use it most effectively? Anyone compare this design to direct radiating speaks? Is this the same concept or design used in some HT surround speakers? BTW, please don't hesitate to correct my terminology.

RGA
08-31-2004, 09:38 AM
Mirage makes such speakers - the same company owns Energy and Athena - Tag McLaren is involved somewhere in the soup as well I believe.

Linn uses the rear firing tweeter as does VonSweikert --- some have had better luck turning therear firing tweeters off - it will depend on your room. I have not heard them sound right yet - they sound different but the reflected waves seem to clutter up the direct sound too much so while it is interesting it seems to sounded sluggish or even distorted. You need to work with the room and positioning a lot.

topspeed
08-31-2004, 11:12 AM
The Energy entry was from their former highend range the Audissey. It came in about three different sizes, but its unique characteristic was its 2 tweeters. The one firing to the rear was supposed to provide more "air and space." Has anyone heard this speaker? Yes, the Audissey APS5+2. My good friend has his connected to a Halo C2/CJ set-up in a dedicated listening room (lucky schmuck). The Audissey's are a different bi-polar design in that the rears fire with less volume than the fronts, yet are still in phase. They don't just have tweeters in back, they also have mids with the powered subs firing on either side. Very nice speakers with dynamics to burn. Even in his well treated room, the bass has to be turned nearly all the way off or it's simply overwhelming. He uses a set for his critical listening as well as another for his HT room.
When the Verita line replaced the Audissey, did Energy go to a single tweeter direct approach? Yes

What manufacturers use the 2 tweeter or omnidirectional design for mains and which ones use it most effectively?Mirage, B&O, Bose (sorta), Von Schweikert, Def Tech, Gallo (omnidirectional), Wilson, and you could argue panels are this way as well. On the VSA, the Rear Ambience Tweeter is user adjustable to compensate for placement and room interaction. I don't know if you can do this on the others.

Anyone compare this design to direct radiating speaks? All the time. We do listening sessions (or is it wine tasting parties :D?) at his place all the time. Whether wine or speakers, it's really just a matter of taste.

Is this the same concept or design used in some HT surround speakers? No, those usually have speakers firing in 2, 3, or even 4 directions either bi-pole (in phase) or di-pole (out of phase) depending on placement and/or preference. The key with those surrounds is to diffuse the soundfield whereas a true bi-polar main is attempting to add depth to the soundfield.

dean_martin
08-31-2004, 11:36 AM
Thanks for the info RGA and the very thorough response from you, Speedy. I've only seen two pairs of Audissey on audiogon and ebay over the last several months. I guess one can interpret this as buyer satisfaction. Of the manufacturers listed, the one I'm most familiar with is Def Tech, but my knowledge is limited to what I've read here at AR. From what I recall, people are either hot or cold on these. I guess it IS a matter of taste.

chimera128
08-31-2004, 05:39 PM
If you are interested in bipolar/omnipolar/dipolar designs you should go and take a listen. When I was going to buy my current system I was looking at various designs from Martin Logan, B&W, Energy, Monitor Audio, Magnepan and basically any other speaker manufacturer that I could lay my hands on. In the end I liked the "spacious" sound and built-in subs of the BP7000SCs more than the others. It was an interesting experience though because the B&W salesperson tried to explain that with a bipolar design I would hear (in stereo listening) voices being reproduced from many directions instead of being centered. I have never experienced this. I have my towers aimed at the listening position and the voices always seems to come from my center channel (slightly above and dead center of the towers), unless they are positioned differently in the recording. Setup is critical with bipolar speakers, I would say more so than with direct radiators, and you have to make sure you have the space for them to be effective.