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JohnMichael
03-02-2010, 12:22 PM
Sunday evening I had the pleasure of attending a concert and the Russian National Orchestra was performing. The music was incredible and I am familiar with the Rachmaninoff's "Piano Concerto No. 2" but heard for the first time Tchaikovsky's "Symphony No. 4". While listening to the music I thought about some of my stereo system choices.

I have always enjoyed speakers with very good imaging. After this concert I have been thinking I might enjoy a pair of speakers with a more omni-directional radiation pattern. The Ohm Walsh speakers, The Shahinian Obelisks and even the Bose 901's crossed my mind.

What I was wondering is does anyone have any suggestions or experience with omni speakers? I am only interested in a stereo pair. Having never shopped for any I am not aware what all may be out there in the speaker market.

After the concert I played the Piano Concerto No. 2 with Lang Lang on piano. I was pleased but knew it was no live performance but this is the most listenable system I have owned. In the past I found it hard to listen to the stereo with the memory of the live performance.

RGA
03-02-2010, 04:08 PM
I would suggest you look into the 360degree MBL loudspeakers http://www.dagogo.com/View-Article.asp?hArticle=705

I am not entirely convinced this is the only option - corner loaded speakers do the same thing like mine or from companies like Trenner and Freidl's RA Box or "Classic Audio" or even perhaps Allison if they're still around. They are further away from the listening position and "typically" the secondary reflected waves follows the initial wave at such a speed that no one can hear it - provided it has a very good stereo fill in the center (some do some don't) then you will have a giant stage without the typical "holes" you get from traditional free standing designs. Id well designed you get less room related issues as well - and of course added bass and sensitivity.

If the speaker also has a wide listening window then directionality is not an issue either if the design is competent.

Other options if corners are not an option would be the Even the terrific Gallo 3.5 which has a 180degree window with its unique curved tweeter. I am less thrilled by speakers using rear firing tweeters or the likes of Bose because they serve to be ambiance generators and it sounds cool for awhile but the drawbacks are plenty.

The MBL kind of designs may be your best option but they're very expensive and they suffer in other areas - front to back dynamics just isn't there - so while they sounded quite spectacular on a stage and listening window front there wasn't the natural drive of instruments that you would get from say a drum set or stand up bass or a trumpet. In other words rather than instruments projecting forward in a believable way like a trumpet player on stage - you get this sort of stayed flat presentation. On the flip side to that though you get a greater sense of the stage - and you can pretty much sit or walk anywhere in your room and get a very similar effect. Pretty cool actually!

I didn't get the pricing in the MBL room unfortunately so I don't have any idea of how much those kinds of speakers run - but MBL is far from cheap. Probably $50K+ is what I am guessing.

The other thing to consider about speakers like the Bose 901 is that while they do create massive stages - they create massive stages for everything whether they have them or not. IMO they're not even remotely accurate to the recording - they have a signature "shaped" sound and they funnel all music through that "Shape" - ie forcing the triangle or the circle or the rectangle through the "square" - some other designs I feel do pretty much the same thing.

audio amateur
03-02-2010, 04:14 PM
I would suggest you look into the 360degree MBL loudspeakers http://www.dagogo.com/View-Article.asp?hArticle=705
You sure AN don't make an omni-directional speaker? :smilewinkgrin:

JohnMichael
03-02-2010, 06:21 PM
I would suggest you look into the 360degree MBL loudspeakers http://www.dagogo.com/View-Article.asp?hArticle=705

I am not entirely convinced this is the only option - corner loaded speakers do the same thing like mine or from companies like Trenner and Freidl's RA Box or "Classic Audio" or even perhaps Allison if they're still around. They are further away from the listening position and "typically" the secondary reflected waves follows the initial wave at such a speed that no one can hear it - provided it has a very good stereo fill in the center (some do some don't) then you will have a giant stage without the typical "holes" you get from traditional free standing designs. Id well designed you get less room related issues as well - and of course added bass and sensitivity.

If the speaker also has a wide listening window then directionality is not an issue either if the design is competent.

Other options if corners are not an option would be the Even the terrific Gallo 3.5 which has a 180degree window with its unique curved tweeter. I am less thrilled by speakers using rear firing tweeters or the likes of Bose because they serve to be ambiance generators and it sounds cool for awhile but the drawbacks are plenty.

The MBL kind of designs may be your best option but they're very expensive and they suffer in other areas - front to back dynamics just isn't there - so while they sounded quite spectacular on a stage and listening window front there wasn't the natural drive of instruments that you would get from say a drum set or stand up bass or a trumpet. In other words rather than instruments projecting forward in a believable way like a trumpet player on stage - you get this sort of stayed flat presentation. On the flip side to that though you get a greater sense of the stage - and you can pretty much sit or walk anywhere in your room and get a very similar effect. Pretty cool actually!

I didn't get the pricing in the MBL room unfortunately so I don't have any idea of how much those kinds of speakers run - but MBL is far from cheap. Probably $50K+ is what I am guessing.

The other thing to consider about speakers like the Bose 901 is that while they do create massive stages - they create massive stages for everything whether they have them or not. IMO they're not even remotely accurate to the recording - they have a signature "shaped" sound and they funnel all music through that "Shape" - ie forcing the triangle or the circle or the rectangle through the "square" - some other designs I feel do pretty much the same thing.



Yes sadly the MBL's are out of my price range. The Monitor Audio RS 6's do create a soundfield that is wider than the speakers with some recordings. I guess I am thinking of speakers that would do this for all my classical recordings.

Bose 901's are not really in contention but an example of some of what I want. I sadly do not have corners available for speakers. I am not as interested in pinpoint imaging as I have been. I want that enveloping sound of a live classical concert from one pair of speakers. I am not concerned about the technology that will get me to that point.

I will check into some of the other speakers you mention. I am not sure if I will make any changes soon since my rock and jazz recordings sound so good with the MA RS 6's.

Feanor
03-02-2010, 06:55 PM
Sunday evening I had the pleasure of attending a concert and the Russian National Orchestra was performing. The music was incredible and I am familiar with the Rachmaninoff's "Piano Concerto No. 2" but heard for the first time Tchaikovsky's "Symphony No. 4". While listening to the music I thought about some of my stereo system choices.

I have always enjoyed speakers with very good imaging. After this concert I have been thinking I might enjoy a pair of speakers with a more omni-directional radiation pattern. The Ohm Walsh speakers, The Shahinian Obelisks and even the Bose 901's crossed my mind.

What I was wondering is does anyone have any suggestions or experience with omni speakers? I am only interested in a stereo pair. Having never shopped for any I am not aware what all may be out there in the speaker market.

After the concert I played the Piano Concerto No. 2 with Lang Lang on piano. I was pleased but knew it was no live performance but this is the most listenable system I have owned. In the past I found it hard to listen to the stereo with the memory of the live performance.
I owned a pair of Ohm F's for several years. In retrospect I regret selling them more than any other stereo component I've owned. They had an expansive soundstage but image pretty well just the same, assuming you kept them 2-3 feet from any wall. And the good news was no sweet spot; you got decent imaging almost anywhere in the room.

http://www.ohmspeakers.com/images/walshF-med.jpg

Ohm is still in business selling omni speakers direct online; see HERE (http://www.ohmspeakers.com/). I haven't heard any of their recent designs, though. They offer a home trial of 120 days.

Mirage, now sadly under the control of Klipsch, is still making various "Omnipolar" models; see HERE (http://www.miragespeakers.com/na-en/).

Mr Peabody
03-02-2010, 07:35 PM
JM, have you listened to any Martin Logan? Although not my favorite match with Krell the ML's do present a very live presence to music.

RGA
03-02-2010, 07:35 PM
Yes sadly the MBL's are out of my price range. The Monitor Audio RS 6's do create a soundfield that is wider than the speakers with some recordings. I guess I am thinking of speakers that would do this for all my classical recordings.

Bose 901's are not really in contention but an example of some of what I want. I sadly do not have corners available for speakers. I am not as interested in pinpoint imaging as I have been. I want that enveloping sound of a live classical concert from one pair of speakers. I am not concerned about the technology that will get me to that point.

I will check into some of the other speakers you mention. I am not sure if I will make any changes soon since my rock and jazz recordings sound so good with the MA RS 6's.

Soundstaging is generally recording dependent and I would rather the stereo reproduce the recording not artificially enhance albums because while a speaker may add some excitement with a big stage to some recordings it could disrupt the good ones.

Omni-directionals are rarely stayed with in the lower price points. Probably why like other designs there are very few makers of them. They sound unique - they're interesting - but that "difference" while ear grabbing may become unsatisfactory long term.

The Gallo 3.5 is affordable if you consider $5,995 affordable. My next page of the show report I discuss this speaker a fair bit. I think it has the advantages you seek in that it will create a large stage - and it has a big listening window - wherever I sat on the couch the sound was uniform. It has tremendous bottom end and very clean crisp stop start motion - iron grip timing. My only slight concern was that the treble was a little tipped up but frankly, I know I get beat up for it all the time, I felt it merely shows up the inherent weakness of solid State amplifiers which were being used in the demo. This rooms had less expensive front end kit and it did a disservice - and even then the result was still overall one of the best. They are being very heavily purchased by recording studios and IMO so they should.

The other issue I have is whether their strength will be in classical - it "should" be good but I auditioned Folk "Loreena McKennit", pop "Sarah McLachlan" Rap and rock in that room. They can play at obscene levels without any compression at all and again iron grip and very deep bass. They were very open - sound was very big and because of the timing and impressive control it should handle any orchestra just fine.

This is a speaker I didn't think I would like because I didn't love the 3.1 and I don't love the big slam kind of speakers. But this one had the treble pushed back - it was much more coherent top to bottom. It's worth a try http://www.sixmoons.com/audioreviews/gallo9/ref35.html

The question will be whether they will have the lightness of touch on microdynamics required for the nuanced softer passages - on the macrodynamics and crescendos they will soar. I also happen to think they look cool which certainly doesn't hurt.

blackraven
03-02-2010, 07:52 PM
If you want a live sound then consider Magnepan and Martin Logan but they have a totally different presentation. Magnepan rules with Vocal, Acoustic and Classical music. All you need a good preamp and CDP/DAC with a large sound stage and transparency to take full advantage of the speakers virtue's.

Ohm's are great too!

IBSTORMIN
03-02-2010, 07:58 PM
I have always enjoyed speakers with very good imaging.

I was a fan of pinpoint imaging until I picked up a pair of used Magnepan Tympani 1d speakers. Each speaker is 4' wide x 6' tall and create a very wide soundstage. At first I missed the precise imaging and would switch speakers back and forth. The Maggies sound so detailed and true I fell in love with them and they are permanently in the main system. Live concerts on CD sound incredible. Someone in the "speakers to keep for life" posting called them a "wall of sound". I think it's more than that as they do image out to the sides of the speaker itself. I think the key to the sound is their size and three panel design and none of the newer Maggies are this large. You might look at picking up a pair of these.

Mr Peabody
03-02-2010, 08:31 PM
I heard a 3 piece Gallo set up more toward their entry level and it sounded good on a Jazz sampler. Funny the owner didn't know how they'd do with HT or heavier music material. I'd put them on the list to listen to though.

Poultrygeist
03-03-2010, 06:01 AM
The link below shows a pair of speakers that were never offered commercially as there wasn't enough profit in their simple design. It's the closest to "live" sound I've heard. I just upgraded from the B200 to the new TB drivers. With OB as with a live performance the listening environment is the box.

http://www.6moons.com/audioreviews/roadtour5/roadtour5.html

mlsstl
03-03-2010, 11:35 AM
I owned a pair of Ohm F's for several years. In retrospect I regret selling them more than any other stereo component I've owned. They had an expansive soundstage but image pretty well just the same, assuming you kept them 2-3 feet from any wall. And the good news was no sweet spot; you got decent imaging almost anywhere in the room.

Ohm is still in business selling omni speakers direct online...

I also had a set of Ohm Fs in the late 1970s that I regretted selling. I've never heard a speaker since that sounded quite the same. About six or seven years ago I auditioned a pair of the then-new Ohms (200 Mk II) for two months. They were quite good, but overall simply didn't have the magic I remembered from the F model. I ended up returning them.

However, they do have a generous audition policy. You have 4 months to try them out and still return for a refund. (As I recall you pay shipping, but that's only fair in exchange for such a long evaluation period. In my case the current listening room is simply not suitable for a speaker with a strong side and back radiation pattern.)

If one is truly on a serious quest for an omni speaker, I think you'd do yourself a disservice if you didn't try out one of the Ohms.

JohnMichael
03-03-2010, 12:00 PM
These might be fun to try out. http://www.tektondesign.com/ob45.htm

JohnMichael
03-03-2010, 12:01 PM
I also had a set of Ohm Fs in the late 1970s that I regretted selling. I've never heard a speaker since that sounded quite the same. About six or seven years ago I auditioned a pair of the then-new Ohms (200 Mk II) for two months. They were quite good, but overall simply didn't have the magic I remembered from the F model. I ended up returning them.

However, they do have a generous audition policy. You have 4 months to try them out and still return for a refund. (As I recall you pay shipping, but that's only fair in exchange for such a long evaluation period. In my case the current listening room is simply not suitable for a speaker with a strong side and back radiation pattern.)

If one is truly on a serious quest for an omni speaker, I think you'd do yourself a disservice if you didn't try out one of the Ohms.



Yes for what I am looking for the Ohms with the Walsh driver may be just what I need.

Poultrygeist
03-03-2010, 04:03 PM
Love the tektons but you can't expect lots of bass from a 4.5 inch Fostex.

TheHills44060
03-03-2010, 04:16 PM
Have you considered Castle Acoustics? The Howard and Harlech models both have the up-firing woofer. I have the Howard's and among other great things they throw a sound stage like you wouldn't believe. Definitely my favorite speaker i have ever owned.

Years ago i borrowed my uncle's Bose 501 III's he's had since 1980 and they were decent but just didn't agree with my room. By no means would i ever recommend anything from Bose that is less than 25 years old.

Sir Terrence the Terrible
03-03-2010, 04:18 PM
Sunday evening I had the pleasure of attending a concert and the Russian National Orchestra was performing. The music was incredible and I am familiar with the Rachmaninoff's "Piano Concerto No. 2" but heard for the first time Tchaikovsky's "Symphony No. 4". While listening to the music I thought about some of my stereo system choices.

I have always enjoyed speakers with very good imaging. After this concert I have been thinking I might enjoy a pair of speakers with a more omni-directional radiation pattern. The Ohm Walsh speakers, The Shahinian Obelisks and even the Bose 901's crossed my mind.

What I was wondering is does anyone have any suggestions or experience with omni speakers? I am only interested in a stereo pair. Having never shopped for any I am not aware what all may be out there in the speaker market.

JM, you know me, so I am going to offer a different approach to this topic based on my perceptions as a engineer who has recorded many a live concert in an acoustical environment. Perhaps your answer is not a omni directional speaker, but a multichannel speaker system instead. I say this because the concert hall experience is not a front loaded listening environment, it is a multi-directional listening environment based on our hearing of multiple long and short complex reflections off of various surfaces coming from different directions. A two channel omni directional speaker based system would make the assumption that recorded reflections would be coming from a single direction, and our listening space provides the room "tone". That is not so in a multichannel system (or a concert hall either) where you can have specific imaging (maybe not as specific as a recording played back through speakers) emanating from the front, and a diffused location based ambience coming from the rear channels whether there are two or four of them. What you desire also must be measured by a "they are here" or "I am there" kind of listening experience/desire. The reality is, if the approach is a two channel with complex frontal reflections with your room tone, all recordings will exhibit the same room tone, even if there is a different pattern of "recording hall" reflections with a different room tone. A multichannel system can capture the "recording hall signature" much more accurately than a two channel system can.

Keep in mind that a concert hall usually has a lot longer of a reverberation time, and a longer reflection path of early arriving signals to the ear than our rooms do.


After the concert I played the Piano Concerto No. 2 with Lang Lang on piano. I was pleased but knew it was no live performance but this is the most listenable system I have owned. In the past I found it hard to listen to the stereo with the memory of the live performance.

That is because a live performance involves the acoustical signature of the performance place, and the stereo incorporates the room signature of your personal listening space. They are so different, it is difficult if not impossible to get them to match, even with high resolution highly transparent omni-directional speakers and signal chain. It is not the reproduction chain in the case of high resolution system, it is the size of the space.
Having a actual speaker and assigned channel in three direction across the front, at least one on the sides, and two in the back rear can map the acoustical signature of a live space much better than a two channel system can based solely on the ability to project direction, and more of the reflections of a live acoustical space.

This is just my opinion, and I do not want to incite a multichannel versus stereo debate.

JohnMichael
03-03-2010, 05:35 PM
JM, you know me, so I am going to offer a different approach to this topic based on my perceptions as a engineer who has recorded many a live concert in an acoustical environment. Perhaps your answer is not a omni directional speaker, but a multichannel speaker system instead. I say this because the concert hall experience is not a front loaded listening environment, it is a multi-directional listening environment based on our hearing of multiple long and short complex reflections off of various surfaces coming from different directions. A two channel omni directional speaker based system would make the assumption that recorded reflections would be coming from a single direction, and our listening space provides the room "tone". That is not so in a multichannel system (or a concert hall either) where you can have specific imaging (maybe not as specific as a recording played back through speakers) emanating from the front, and a diffused location based ambience coming from the rear channels whether there are two or four of them. What you desire also must be measured by a "they are here" or "I am there" kind of listening experience/desire. The reality is, if the approach is a two channel with complex frontal reflections with your room tone, all recordings will exhibit the same room tone, even if there is a different pattern of "recording hall" reflections with a different room tone. A multichannel system can capture the "recording hall signature" much more accurately than a two channel system can.

Keep in mind that a concert hall usually has a lot longer of a reverberation time, and a longer reflection path of early arriving signals to the ear than our rooms do.



That is because a live performance involves the acoustical signature of the performance place, and the stereo incorporates the room signature of your personal listening space. They are so different, it is difficult if not impossible to get them to match, even with high resolution highly transparent omni-directional speakers and signal chain. It is not the reproduction chain in the case of high resolution system, it is the size of the space.
Having a actual speaker and assigned channel in three direction across the front, at least one on the sides, and two in the back rear can map the acoustical signature of a live space much better than a two channel system can based solely on the ability to project direction, and more of the reflections of a live acoustical space.

This is just my opinion, and I do not want to incite a multichannel versus stereo debate.



I agree Sir T and if I had a dedicated listening room multi-channel would be the way to go. I have heard some very nice multi-channel systems. I do listen in the nearfield so some of the rooms tones do not interfere when I am in my listening chair. Since I am very decor concious two speakers are all I can tolerate in the living room. The only way I could have a multi-channel system is if I evict my roommate. Thinking....:ihih:

poppachubby
03-03-2010, 08:27 PM
John, have you heard any Martin Logan? I had a religious experience with a pair of ESL's. You want room filling sound with a giant stage, they've got it.

Hyfi
03-04-2010, 07:03 AM
I used to have a pair of Mirage M-790s bi-polar floorstanders which had woofer and tweeter in the front and a full range out the back.

They did have a a nice full sound for the $800 bucks they cost at the time. I guess these were the precursor to the later Omni lines. It's been a few years and I replaced them with the Danes.

http://www.minhembio.com/bilder/bild/?pic_id=310277.jpg

E-Stat
03-04-2010, 07:17 AM
Sunday evening I had the pleasure of attending a concert and the Russian National Orchestra was performing. The music was incredible and I am familiar with the Rachmaninoff's "Piano Concerto No. 2" but heard for the first time Tchaikovsky's "Symphony No. 4".
Wasn't the pizzicato in the third movement incredible? I have the Maazel / Cleveland version from 1979.


After this concert I have been thinking I might enjoy a pair of speakers with a more omni-directional radiation pattern.
I think you'll find that most any dipole that is allowed to breathe in the room can achieve the ambience you seek with a wide range of recordings. They come in all flavors. One very popular model with a significant following is the Linkwitz Orion.

rw

Invader3k
03-04-2010, 06:19 PM
Those Tektons have a really interesting design. I'd be curious to see some reviews.

Poultrygeist
03-05-2010, 08:38 AM
Eric's Tektons are fantastic as long as you pair them with his sub. He'll tell you as much.

poppachubby
03-05-2010, 09:04 AM
John, I have been lusting after Tektons for some time. The open baffle and the Model 8. They are a terrific value. I suspect that with your Krell, they wwoouldn''t bee the greatest matcch in the worldd. You may allso havee issues blasting Prison Song, in which case I could always sing for you.

"Following tthe rights movement you clamped down with your iron fist,
ddrugs became coonveniently available for all the kkids"

flippo
03-06-2010, 10:09 AM
Mirage makes omnidirectional speakers

basite
03-07-2010, 08:45 AM
what about small(er) MBL's? I generally don't really like omni directionals, give me a wide soundstage any day, but omni directionals don't seem tickle my mind...

But,
the MBL's did. admittedly I did hear fairly larger ones (a new model, typical floorstander size...) And I was impressed. really...
Ohm walsh are an option too, yet no comparison to the MBL's...

and look for ESS Heil speakers too (well, speakers with ESS Heil tweeters in them...)
and JFYI, thiels do have a fairly large & wide soundstage too, wider than the monitor audio's, but you'll have to get floorstanders then, and go for the CS2.4 or the 3.7 :)
(but of course, I'm biased...)

Keep them spinning,
Bert.

hifitommy
03-07-2010, 11:26 AM
but its not likely. the ohm As and Fs i heard were usually down to one channel as those speakers werent robust enough to endure the power they required to get loud enough for most listening tastes.

martin logans will certainly go loud enough but again, the sweet spot is smaller than consideration as an omni and the sound sitting or standing up can be quite different.

magneplanars fare well from off angle listening so may be an affordable alternative. i have MMGs and my friend has mg12s and they dont make you sit in one spot. yes, things are nicer in the sweet spot but the move from it doesnt slap you in the face.

vandersteens could be a consideration as well. as long as the side walls arent too close. if they ARE close, toeing in away from the sides can tame the overly spacey effect that can come from wide dispersion designs.

minimonitors are another choice to consider (with a sub) for somewhat omni dispersion.

i hope this helps.

poppachubby
03-07-2010, 12:40 PM
So basically, if you have no need to move around the listening room, the Martin Logan are a nice choice. People are always so quick to bring up the sweet spot issue, but in reality, most do their critical listening in one spot. I suppose it's situational for each person.

hifitommy
03-07-2010, 07:49 PM
to be able to move about (in canadian thats aboot) the listening room. also, when having a mancave listening session, you dont want to be too cozy with the other listener.

also, i tight sweet spot ala quad 57s is quite a limitation, the proverbial head in a vise sitch. i dont have this prob with the MMGs btw. and my other speakers are mini monitors like spendor s3/5s, and infinity primus 150s which allow more freedom of movement.

the MLs have a fairly wide SS so more than one can enjoy the dimensional qualities of them. also, the MLs meld nicely with their cone woofers so that is less of a factor than hybrids of decades past like infinity servo-statiks. another good ES is the sound labs but they might be a bit pricey.

JohnMichael
03-07-2010, 08:09 PM
Thanks Tommy for your suggestion of the MMG's. I could easily afford them and I could switch betweeen them and the MA RS6's. The MMG's for classical and the RS6's for rock and jazz.

paulspencer
03-18-2010, 11:31 PM
JM,

Always good to rethink things from time to time.

I've built omni, open baffle and floorstanders with the same drivers all with eq to match a target response. All other things being equal I'd say I prefer omni and open baffle for their sound stage and imaging. The two are more similar than you might expect.

Harman audio do a great deal of blind testing of speakers, and they have found that what most people prefer is easily predictable based on measurements. One of the keys they found was that a speaker should have a smooth polar response transition. Speakers that had a poor polar response were always liked less even where they were much more expensive.

Omni speakers have an even radiation in all directions. I first thought the ideal was flawed and the wrong direction to take, but now I see it as a valid direction. Omnis have the biggest sweet spot you can get. It's difficult to get decent output from an omni and it's also difficult to extend the omni behaviour all the way up. If the treble isn't omni then the transition should be smooth. I've heard a Linkwitz Pluto clone and was surprised at how sharp the imaging was.

Open baffle speakers have a polar response that makes more sense to me. Side wall reflections are reduced due to the dipole null. The same is true with the ceiling. There are strong front wall reflections and you ideally should use diffusive treatments so the early reflections take a longer path.

I find open baffles much more appealing in the midrange. The stereo image doesn't collapse as you move sideways so you can actually simplify a 5 channel system into a 4 channel. (Not that open baffle really makes anything simple). The sound stage is bigger and more realistic. Not quite as sharp but there is much less of a sense of sounds coming from the speakers. If you place them correctly, you can actually cancel out the first reflection from the rear wall.

There is another approach which makes a lot of sense. Dr Earl Geddes designs speakers for constant directivity. Here is an example:

http://www.gedlee.com/summa_.htm

Notice how firstly the polar response is very smooth. You can see off axis due to the waveguide that the response is still fairly flat. Now let's say you sit off axis so you are closer to one speaker than the other. Normally this would ruin the image, causing it to shift to the closer speaker. However, if you toe in this speaker correctly so that it sits at 45 degrees and the speaker axes cross in front of you, something clever happens. The further speaker is on axis. So you hear the top line response in the chart. The closer speaker is a little more on axis. The result is that this placement with this particular design prevents the stage collapsing into the closer speaker. All this is explained in more detail in this paper:

http://www.gedlee.com/downloads/directivity.pdf

I've done quite a bit of rethinking about speakers, and Earl is one of the ones who have given me a lot of food for thought. What I'd like to try is an open baffle speaker using a similar approach, extending directivity control down lower into the midrange and keeping the spacious sound of open baffle. The tricky part is the the waveguide needs more toe in than the mid. 45 degree toe in for a midrange open baffle doesn't sound right at all.

FYI my omni, tl and ob speakers on my blog:
http://redspade-audio.blogspot.com/2009/08/diy-omni-loudspeakers.html
http://redspade-audio.blogspot.com/2009/08/diy-open-baffle-speakers.html
http://redspade-audio.blogspot.com/2009/08/diy-transmission-line-speakers.html

I'm now selling the TL speakers to fund the next upgrade.

Mr Peabody
03-19-2010, 02:51 PM
But what's the bass response like for an open baffle speaker? It seems like it would be similar to a planar or worse. Maybe some bass content but no punch or detail.

paulspencer
03-19-2010, 09:22 PM
I'm not a big fan of open baffle bass, although it could be worth considering in some rooms that are very difficult. It responds to room modes differently. I've taken measurements of open baffle bass compared to my subs. Generally open baffle bass is better SQ but more expensive due to the need to move more air. You need typically four large drivers running say 40 - 120 Hz crossing to a monopole below. They have the same radiation pattern of panel speakers, but with more output and smaller size due to high excursion drivers. They don't benefit from room gain down low as they don't pressurise the room like a monopole. With my particular subs (Rytmik Directservo) I've found there is no SQ improvement, but with most drivers I'd expect a noticeable improvement. I believe the sound is similar to Infinite baffle, but with dipole roll off.

I prefer open baffle for the midrange. It's easy to get a reasonable size panel that will work just fine down to about 80 Hz - low enough to cross to a sub.

Mr Peabody
03-19-2010, 10:35 PM
What is the difference between open baffle and infinite baffle? I haven't heard either in a home set up yet.

audio amateur
10-19-2010, 04:08 AM
What is the difference between open baffle and infinite baffle? I haven't heard either in a home set up yet.
Infinite baffle usually refers to subwoofer drivers that are mounted on a wall and use the adjacent room as their 'box'. The wall on the which the driver is mounted seals off the front sound wave from the rear sound wave. These setups render the drivers very inefficient which means you need to use several large diameter drivers which together can yield obsene SPLs in the sub 30Hz region.
Open baffle speakers are speakers (woof/tweet or full range drivers) mounted an a large sheet of wood. The idea is the same, you need to isolate the front and rear sound waves if you want any bass from such a speaker setup. They are similar to electrostats or planars in that they also fire rear radiating sound waves, but they use conventional dynamic drivers.

Mr Peabody
10-19-2010, 04:01 PM
Thanks, AA

JoeE SP9
10-19-2010, 07:54 PM
You should also consider some Quad ESL 63's. Quads and Ohm F's have always been at the top of my list of speakers to drool on.. They both fit in with my no "monkey coffin's" mind set.

jrhymeammo
10-19-2010, 08:09 PM
Hey John,
It's been a while.

Here is what I've been thinking about doing.
Audio Nirvana Super 10 Alnico.
You can choose drivers and cabinet finish to your taste.

For what you are looking to achieve, the 2.8 Ambience might just do the trick.
Go to the link below and click on Customer Projects for your reference.
http://commonsenseaudio.com/

Peace,
JRA

Florian
10-27-2010, 01:52 AM
About 600 bucks, i have a pair as well.

http://www.duevel.com/Produkte/EPlanets.shtml

http://www.avac.kr/front/ac_mdfile/Product_Img/Duevel/plan_due_1136.jpg