Why MUST my Surrounds be Direct Radiating? (1 Viewer)

[John Morris]

I prefer direct radiators as well. Now if you want my opinion on why here goes. 5.1 is supposed to be discrete sound from discrete portions of the room and a diffuse rearsoundfield goes against that philosophy IMHO. I want to hear discretely in the room where the sound is coming from not a big void of sound in the back of the room.

Shane: From your description of a "diffuse big void of sound", I am wondering if you've ever heard good bipolars which are set up correctly. My bipolars are anything but diffuse, but to get them to sound that way required moving them 4 feet out from the back wall and toeing them in slightly. From there they provide pinpoint imaging while also depth of soundstage, just like a true performance.

When I tried my rear surrounds in direct radiating mode, on many movies the effects and sounds could be pinpointed directly to the speaker. For me, it was very distracting and drew my attention away from the movie and directly to the speaker behind or to the side of me.

Now, I too love some direct radiating speakers. If I could afford it, I'd replace my system in a minute with 6 Aerial Accoustics 10T speakers. Unfortunately, that would cost me around $15K. For the $4K that it cost me, my current 7.1 speaker setup just sounded better to me than any other speakers I tested in that price range.

And, that is my only point of this entire thread... no one should overlook bipolar, dipolar, direct, or hybrid speakers when they are searching for their own holy grail.

 

[John Morris]

For less than hi-end equipment, which provides less than stellar soundstaging and imaging, I suppose it's possible that bi- or dipoles might generate some sense of spaciousness, albeit somewhat phony. In some ways this is akin to the "concert hall" and other DSP's on some receivers: phony, but not necessarily unpleasant.

LOL! Larry: I hate DSPs and never use them. Unfortunately, since my speakers have been discontinued, you can't go and listen to them. However, I'd recommend that you go and listen to some nice Magnapan, Mirage or Martin Logans speakers... then come on back and tell me that these speakers don't image.

In the end, it all comes down to what we like best from within the selections available to us at our budgets. Just like music, speakers are mostly a matter of personal taste.

 

[Larry B]

Merc:
Mea culpa! My error in not realizing that electrostatics are considered bipoles.
I have had limited experience with 'stats and ribbons (not by choice, simply haven't been exposed to many in my travels) but I don't question that they are capable of some amazing things. Based purely on things I've read and discussions I've had, it appears that 'stats must be placed at a considerable distance from the front wall, or else a smearing effect occurs. Can you comment on that?
On separate note, I take any rating done by Stereophile with a grain of salt (or as my college physics teacher used to say, with a grain of malt ) In my opinion, the quality of Stereophile is sinking almost as rapidly as Enron stock. The only publications I have any respect for are The Absolute Sound, and an E-publication I just recently came across, The Audio Perfectionist (which I highly recommend). If memory serves, the author/publisher of the latter, Richard Hardesty, provides an intelligent, and easily understandable discussion of the smearing effect.
Again, sorry for my blunder, and thanks for pointing it out without making me look too stupid
Larry

 

[Randy G]

>>Electrostatics and ribbons are considered bipoles>Dipole and Bipole speakers create voids

 

[John Morris]

Electrostatics and ribbons are considered bipoles

 

[Larry B]

Merc:
The following site provides some info on the effect of bi- and di-pole speakers on imaging. I don't know how authoritative it is; it's simply something I came across.
http://www.audiovideo101.com/learn/a...speakers10.asp
Larry

 

[Hank Frankenberg]

Merc: Thanks, I think folks need to be reminded of the difference occasionally. I built my surrounds from a Speaker City design and they are DIPOLES. The cabinets are a pyramid shape with the drivers on the 90 degree apart sides. I hear both intentionally recorded diffuse sounds and more "pinpoint" sounds just fine. They are a great combination. I'll stick with them rather than go to directs.

 

[John Morris]

Larry: Thanks for the link. I think it provides a nice generalized explanation of the speaker dispersion patterns. However, as we know, rooms and seating postions, relative to speaker placement, probably impact what we hear to a greater extent than driver on box placement. Still, the link provides a nice starting point.

Probably, the reason that I like my bipolars (BTW, I don't like most bipolars nearly as much as my old ones) is that to me they sound the most like a live performance.

[rant]Sound of opening of big can of worms[/rant]

When a guitar is plucked or a violin bowed, the sound emanates in all directions, not just directly toward the listener. Of course, most large concerts are amplified and the sound tossed at the listener using direct radiators. However, the massive arena reflections and the addition of the performers own amplified monitors cause a sound dispersion pattern more like bipolars than direct radiators... IMO. Additionally, bipolar radiation also acts to extend the soundstage beyond the space between your speakers, thereby, making the listening experience more like a live performance.

 

[Larry B]

Merc:

And thank you for the insightful reply.

My own personal tastes differ somewhat, but as my late Mother used to say, that's why they make chocolate AND vanilla!

Regards,

Larry

 

[Craig Morris]

Bipolar speakers ARE capable of precise imaging when properly set up.

I recently went on a speaker auditioning binge, trying to find a replacement for my Mirage OM-6's. I have auditioned B&W, Totem, Paradigm, Mirage, PSB, Revel and others. Nothing I heard (except some insanely expensive Revels) made me want to change my OM-6's. Imaging and soundstage are superior on my current speakers. Unfortunately, I have no choice but to change them as the bass is overpowering in my small room.

Now the question is, how do I replace them? I wish I could chop off the top half and use them as stand-mounted monitors. That's how good they are.

 

[Andrew Pratt]

I think that one of the most important factors in choosing which type of speaker to use has to be the room. Simply put some rooms are not set up to have direct rading speakers positioned correctly so in those cases bi or dipoles make more sense. I've heard both types and when done right they both can excel. Personally I run Maggies all round so technically I have dipoles but there is a big difference between a dipole thats mounted to the side of the listener and a large dipole panel speaker that is standing a few feet behind the listening area...trust me I have no problems with either a difuse sound stage or pin point imaging if needed Anyway my point was that the rooms we use will play a large roll in determining what type of speaker suits best and that labeling di/bipoles as being bad for rear duty is silly when you rememeber that all planners, electrostats and bipole tower speakers like the Energy 2+2s and Def Techs etc all can essentially be set up like a normal direct radiating speaker

 

[StevieC]

So then what are the opinions of "tripole". Both M&K and VonSchweikert make some surrounds of this type. I have not heard them but have been curious. If there are settings where you could switch between tripole, monopole and dipole, you could have lots more fun adjusting to different sources. Anyone have such a setup ?

 

[Larry Chanin]

Why MUST my Surrounds be Direct Radiating?
Hi all:
I think in answering this question it would be wise to qualify our remarks into a few categories:
First Music Versus Movies.
I’m primarily interested in movies so I’ll leave the discussion of multi-channel Music to others to argue the merits of direct radiating surrounds. However, I suspect as others have already mentioned, that there is a difference in which type of surround speakers are generally most suitable for music.
With regard to Movies I think we need to further qualify our remarks into two more categories:
5.1 surround Versus 6.1/7.1 surround.
But before getting into that, I’d like to touch on something really basic that we all know, but we sometimes forget when we get into these kind of discussions. That is, movie soundtracks are not designed for the home theater, or home theater speakers. They’re designed for commercial movie theaters with lots of space and arrays of professional sized direct radiating speakers. The combination of sufficient distance between the listener, and speaker arrays can create diffuse sound fields (surround effects) in addition to “smack-you-in-the face” direct sounds. Obviously, the sound engineer has to design for both types of sound. So if we’re trying to reproduce what the director and sound engineer had intended, then we must address both types of sound. On the other hand, if you’re one of those rugged individualist who knows what they like regardless of the original design, then none of all this discussion is really very relevant.
In home theaters we do not have the amount of distance nor speaker arrays to create a commercial surround effect. So we need to devise ways to create diffuse sounds fields differently than is done in the commercial theaters. This can be done a number of ways:

• positioning the listener in the null of a dipole speaker.
• sending a mono surround signal to two direct firing speakers that are spaced some distance apart.
• using direct firing speakers and aiming the sounds over the heads of the listeners, or
• a combination of some depending on the size and layout of the room.

Therefore, it should be possible to create surround effects from either dipole and/or direct radiating speakers, the question then is, “Which is best?”. I think the answer to that question depends on what type of surround set-up you have, 5.1, 6.1, 7.1.
I believe that if you have a 5.1 set-up you have more trade-offs to deal with than a 7.1 set-up. What I mean is if you select direct radiating surrounds in a 5.1 set-up you may be somewhat sacrificing the ability to reproduce diffuse surround effects. Conversely, if you select dipoles you may be sacrificing the ability to localize sources. On the other hand with a 6.1 or 7.1 set-up it is possible to select different types of speakers for back versus side surrounds.
In my set-up I have dipoles on the sides and a small array of three direct radiating speakers in the rear. With this arrangement I hear a lot of very directional sounds panning forcefully from front to back of the room. The dipole speakers on the sides provide that enveloping ambience effect associated with surround sound fields. I feel this arrangement gives me the best of both types of speakers.
If I had a 5.1 set-up I'd choose dipole surrounds, to provide diffuse surrounds to supplement the very direct sounds coming from the front.
Larry

 

[Chris Zell]

I didn't know whether to buy dipole or direct (I doubt there is much that much difference in sound dipole vs bipole for surrounds) - hadn't had enough experience to know.

Maybe you'll want direct for movies, dipoles for music (what I do mostly), or vice versa.

Maybe you'll change your mind after a while

Only one sensible solution - buy surrond speakers that can be switched back and forth between direct and dipole. That's what I did, and I sleep well at night.

Cheers,

Chris