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shaun
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omnidirectional speakers

I am just starting my audio education. There is such huge range of equipment available that I would like to maybe learn a few rules of thumb (if they exist) befor I start demo-ing. I would prefer not to waste my sellers time or my own. I have been researching equipment for a two channel system with a total budget between$5-6,000. It will play in a fairly large room with hard surface floors that is an "L" shape, 9' ceilings with about 14'x25'. Asthetics are somewhat important(married) as is the lack of speaker placement options. I would like to hear from anyone using omnidirectional speakers ie. duevel, or, those with horns. Are there certain sounds inherent to certain designs? Music taste between my wife and I ranges from ac/dc to opera. I have not been able to search this site for the info I crave. please help.

Kal Rubinson
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Re: omnidirectional speakers

Large room with hard surfaces and constraints on speaker positioning? You have a tough problem and I cannot think of any specific equipment that will cure it.

The dimensions you give are similar to the listening leg of my "L" space but it is fairly well populated with soft stuff as well as some room treatments. Without either, you will get lots of reflections that will compromise imaging and lots of emphasized room modes.

How about another room?

Kal

gkc
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Re: omnidirectional speakers

Rules of thumb. As Kal mentions, hard surfaces can be death to realistic soundstaging and imaging. Also, they can harden timbres. You can judiciously soften things up a bit with various wall-hangings -- rugs, and framed cloth. You will almost certainly need area rugs in front of (and maybe behind) your speakers. Awhile back, John Marks discussed how floor and ceiling reflections can screw up imaging, so you may need something above and in front of your speakers. I wish I could remember the issue, but I'll try to look it up. The general rule for placing such absorptive materials is about a third of the way from your speakers to your main listening position, about tweeter-high.

You mentioned omni-directional designs. Mirage makes several (I used to own their M1-si's, a discontinued model). They are reputable, but I found them too splashy in the upper midrange for even my well-padded cell. Tastes vary, so you should listen for yourself. You can buy factory-direct Ohm speakers (Walsh tweeters, which are omnidirectional) for 2-5 grand, with a 30-day return guarantee. These are true high-end designs and shouldn't be ignored just because they haven't been reviewed in Stereophile or TAS. I own Triangle Volante 260's, and I am absolutely nuts over them. They are not omni's, but have both front and rear firing mids and tweeters. They are very spacious. I hope Buddha sees this -- he has Acoustech 2+2 electrostats. Most electrostatics and planars are front-and-rear firing, which helps create the illusion of space. However, there can be reliability issues, and there is definitely a "fuss" factor (placement options are generally few, the electrostatics have to be plugged in to AC outlets, and frames can be flimsy). The best known planars are made by Magnapan. The best known electrostatics are made by Quad, Martin-Logan, and Sound Labs. They can be VERY expensive, but 2-3 grand can get you into some nice speakers. Magnapan has a $1500 model that many audiophiles just love. Check them out. Make sure your dealer will warranty possible problems. My Volante's are about to be discontinued. I don't plan on upgrading mine, but many will, and this may be a good chance for you to pick up used/demo bargains. They are in the "Stratos" line of Triangle Speakers, and the top two in the line ($4,000 - $6,000 MSRP) have the front-and-rear firing design. Don't marry the idea you have to have omni's to get great sounstaging and imaging -- listen to conventional designs as well. Good luck, and keep in touch. Clifton

gkc
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Re: omnidirectional speakers

Ooops. I forgot to mention. Most high-end speakers sound their best at LEAST 3 feet away from side and rear walls. Your room is almost exactly the same size as my apartment listening room. My speakers sound best 34" (center of the tweeter to the wall) from side boundaries and 72" from the rear wall behind the speakers. You will just have to live with that, or, as Kal says, get less sound than you paid for. Or, you can get speakers that, by design, sound good closer to the walls or in corners. Allison makes such a speaker -- it is designed for corner placement. At the recent Home Entertainment show, Roy Hall exhibited some Epos speakers (their $2,000 floorstanders, a slim tower design about 3' tall) that sounded super stuffed into the corners. I was as impressed by the sound in that room as I was by $100,000+ set-ups on display elsewhere. Unless you do a lot of room treatment, you should avoid horn designs --they tend to be quite aggressive in the upper midrange and high frequencies. This is a subjective judgment on my part, and a general rule only. If your auditioning universe gets too big too quickly, these would be the first I would eliminate from further consideration. Be very, very careful about aggressive-sounding speakers. They can be impressive in the show room and give you whanging headaches when you get them home: being impressed by 10 minutes of overly bright sound in the showroom (better designs might sound dull by comparison) is one thing...having to live with that choice at home is quite another. Cheers, Clifton

Kal Rubinson
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Re: omnidirectional speakers


Quote:
Ooops. I forgot to mention. Most high-end speakers sound their best at LEAST 3 feet away from side and rear walls. Your room is almost exactly the same size as my apartment listening room. My speakers sound best 34" (center of the tweeter to the wall) from side boundaries and 72" from the rear wall behind the speakers.

This amazing. As I said, my room's dimensions are almost identical and I, too, have my L/R speakers those same distances from those boundaries!! Of course, the 34" distance will give a bit of a null at 100Hz due to SBIR.

Kal

Buddha
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Re: omnidirectional speakers

Clifton's many many many many years on this planet make for a Hi Fi guy who gives great pointers.

Did I use enough "many's?"

He's dead right.

I'd add some heretical opinion:

Allowing for breathing room, I've found planar/omni speakers to actually make for relatively easy and satisfying placement in live rooms.

There aren't really as many bad bugaboos in this regard as you may think.

Instead of typing all night, I'll now go look for a good link or two that mentions placement, but with just the standard flashlight/mirror trick and some creative use of wall hangings and floor furnishings, you should be able to really have some true high fidelity fun!

_____________________________
_____________________________

OK, that being said, and with your 6K budget (we always use the high end of your figures here)...

The used market is full of terrific gems. True, honest to God gems!

I'll look for examples.

gkc
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Re: omnidirectional speakers

Too many many's for my liking, far too few for the reality of it all. Sigh. Is Acoustech still making electrostatics, or is that currently a used market only? I can remember the 2+2's from the old days, and they were marvelous. But that was before after-market wires and the other tweakery available nowadays. I haven't kept up with the brand. They used to make amplifiers, too, didn't they? Remember when an honest 60 watts per side was tons of power? Oy.

JoeE SP9
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Re: omnidirectional speakers

ESL's and Magneplanars are di-polar the Mirages are bi-polar. In dipolars the rear wave is out of phase with the front. In bipolars the rear wave is in phase with the front. Neither of these types is omnidirectional although they share the same general dispersion patterns.
Ohm's using the Walsh tweeter are omnidirectional in the treble area. More expensive Ohms that use the full range Walsh driver are true omnidirectionals.
Acoustat is no longer in existence in the US. There is a Chinese company making ESL's under the name. I have heard very good things about the product. Yes Acoustat made amplifiers at one time. It is currently only a used market for Acoustat products. I own two pair of Acoustats, Spectra 22's and Model 1's. They are still marvelous and shame most newer boxes of any price. I have mentioned the reliability factor in another thread. IMHO they are the most reliable ESL's ever made.

gkc
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Re: omnidirectional speakers

Yeah, I knew about the bi-, di-, and omni distinctions. Reading between the lines, I thought the original poster was lumping them all together. I think, though, that Mirages newer designs ("omnisat"??) have abandoned the older bipolar configuration. Is it "Acoustech" or "Acoustat"? You would obviously know, since you own them. Did the name change from one to the other, or am I just having a senior moment in remembering "Acoustech"? The ones I heard resembled the KLH 9's (which I owned for awhile), with their similar sizes and ecru grilles, although the KLH had vertical wooden slats while, as I recall, the Acoustat (tech?) had a plain front. Also, as I recall, the KLH was more difficult to drive. Cheers, Clifton.

Kal Rubinson
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Re: omnidirectional speakers


Quote:
Yeah, I knew about the bi-, di-, and omni distinctions. Reading between the lines, I thought the original poster was lumping them all together. I think, though, that Mirages newer designs ("omnisat"??) have abandoned the older bipolar configuration. Is it "Acoustech" or "Acoustat"? You would obviously know, since you own them. Did the name change from one to the other, or am I just having a senior moment in remembering "Acoustech"? The ones I heard resembled the KLH 9's (which I owned for awhile), with their similar sizes and ecru grilles, although the KLH had vertical wooden slats while, as I recall, the Acoustat (tech?) had a plain front. Also, as I recall, the KLH was more difficult to drive. Cheers, Clifton.

Acoustech and Acoustat were different companies and your memory about Acoustech is correct. The Acoustech X was a powered version of the KLH9.

Kal

gkc
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Re: omnidirectional speakers

Thanks, Kal. I guess I haven't heard any of the Acoustat models. Anybody out there besides Buddha and JoeE have 'em? Joe, are they easy enough to drive, or do they have special needs? Cheers, all.

JoeE SP9
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Re: omnidirectional speakers

I have driven my current and previous ones with everything from an Onkyo receiver (not mine) to a Krell KSA-100. They like voltage but seem to be a fairly easy load for most amps. I wouldn't use anything less than 100wpc or so to make them open up. Myself, I like them driven by tubes. I can get away with that because I bi-amp and only run them from 85hz up. My subs handle all the bass.

garthr2
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Re: omnidirectional speakers

Greetings Shaun,

Well ...... I'll just throw this out there ...... it's not what you'd consider "high end" ...... but it may be worth the audition. I've been looking for some omni type apeakers also .... and came across these from the founder and innovator of EPI .
I found this review http://www.positive-feedback.com/Issue26/direct_acoustics.htm

They appear to be a refinement of the older EPI 201 and Epicure Model 20. See some here: http://www.humanspeakers.com/e/epi201.htm
http://www.humanspeakers.com/e/epicure-20.htm

I've not heard any of these ..... but the EPI models have been around a long time and some members in this forum probably have or have had these. The EPI models used 4 drivers per speaker.... two front firing and two upward firing.The Direct Acoustic models uses just 2 upward pointing drivers .

What I like about the Direct Acoustic speakers is they can be put against the wall ... or just inches.... whatever works.

anyways ..... just to give you another option for confusion .......

ALF in AUS
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Re: omnidirectional speakers

Hi Shaun and all ...
I am told that these Decware radial speakers sound really, really good - but I haven't heard them personally ...
http://cls.audiogon.com/cgi-bin/cls.pl?spkrfull&1161825364

www.decware.com/radials/designnotes.htm

I did hear a set of German (I think) radial, omnidirectional speakers that looked sorta similar - they were just sensational! The speakers themselves seemed totally 'invisible', leaving a beautiful wide and deep sound image that seemed to extend beyound the bounds of the room ... I was rapt, but they were well and truly out of my price range.

At the present, and probably permanently, I'm into Open Baffle speakers (diy) ... they don't have so many room mode troubles as boxes, and deliver a 'real' and free sound that is very addictive ... but they do need a lot of space around them.
If I was buying speakers, I'd be very tempted by open baffles like these - not omnidirectional, but in my humble opinion more life-like than omnidirectional ...
http://www.nightingale.it/english/lyra.html

Have fun in whatever you do.

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