Try it! You'll probably like it. Placement in the room can be critical. My best system is the Linkwitz 521 with one amp per speaker, eight amps in total. Very easy to build; no annoying joints to master! Enjoy the music.
Open Baffle Experience
Much has been said about open baffles, including an epic website by the late, great Dr. Linkwitz but I've only heard them really once, playing absolutely garbage music (thanks Pure Audio!) at a hotel.
I'm talking here about dynamic drivers in single baffles without enclosures, not ESLs or Magneplanar type systems.
I'm curious who has had them, and who kept them or went back to "conventional" boxes?
I'm not really looking to buy speakers, but I did start thinking about this because of a kit over at Madisound made with high quality drivers.
157 responses Add your response
Out of phase compared to what?
|
The front and back waves are not in time with each other. Show me an open baffle that has both back and front in time.
the frequency response is a mess. |
@jaytor , I am a huge open baffle fan. I have been using open baffle loudspeakers exclusively since 1979, they are called ESLs. They are full range (except sub bass) line source dipoles. The entire range from 100 Hz to 20 kHz is open. I also have been building subwoofers since 1993. You can see my shop on my system page. Granted, subwoofer enclosures are a royal PITA but trying to use an open baffle driver at wavelengths between 10 and 40 feet is a hopelessly inefficient way of going about making sub bass. What you have are floor shakers. It is also not about what you hear down there but what you feel. Who knows? Given the crappy construction quality of most subwoofer enclosures you might be better off where you are. |
Eric, click on my UN then click on picture to see my OB Emerald Physics 3.4s. You will notice 4 tall black tubes, 2 by the speakers and 2 on each side of my soon to be replaced vertical rack with a horizontal 2" thick solid Maple table. The 2 by the rack have been moved to the opposite sides of the 3.4s. The Oppo 105 was sold, and a LSA Voyager GaN 350 replaced the EVS 1200 and the subs were sold. I have recently rewired the entire system with Ali-E Odin Gold IC/PCs and Odin 2 speaker cables + 2 PCs from Amazon one from 20amp dedicated line to my Core Power 1800 and the Audio Alchemy PS 5, outboard PS EPs can be picked up rather inexpensively if you have the patience |
@kenjit said.... "That is not true. Open baffle designs are WRONG. They emit sound that is out of phase out the back end. If you can show me an open baffle design that can emit sound IN PHASE not OUT OF PHASE from the back end then I will happily throw my box speakers away and we can all enjoy perfect sound with no cabinet resonances. I dare you."
I don't listen to open back speakers from behind. I listen to them from the front, as they are designed to operate. So the out of phase condition you refer to only occurs at frequencies that "wrap around" the baffle. That more likely will occur at lower frequencies, dependent on the size of the baffle. The longer the wavelength, the larger of baffle / distance from the back of the driver to the point where the rear wave can interact with the front wave. Look at the Linkwitz open back system woofer section. It has that shape with particular emphasis on wrap around to lengthen the distance to decrease wrap around effect. The other drivers also use that calculation, but in a less obvious way. The crossovers are specifically designed to take into account the wrap around effect to help low frequency rolloff. It's ALL in the design of the system. I will admit that sub-80hz requires very large baffles / crossover control that assists open baffle speakers. Even then the bass performance seems a bit thin to my taste. The sound coming from the back of the open baffle speakers IS out of phase with the front, but that in NOT necessarily a factor IF THE DESIGN TAKES THAT INTO CONSIDERATION. Speakers are directional as the sound wavelength increases beyond the speaker diameter. That makes the use of larger drivers more desirable because their rear wave output is aimed away from the front and can be diffused. Need proof? Look at a raw driver's response curve as the frequency increases. Note the frequency response rolloff at 15 and 30 degrees. Listen to speakers off-axis to reinforce that fact of physics. That is taken into the design considerations for baffle size and rear wave control. It's not difficult to manage the back wave of speakers from the upper bass upward. Artificial Ficus trees are the easiest and least expensive. Placed around the room, they are every effective diffusers. Used behind open baffle speakers, they are excellent in reducing back wave interference. But there's no denying that Acoustat, Magnepan, Quad, and other manufacturers have developed quite nice sounding open back systems. But if you are ABSOLUTELY CONVINCED that box speakers are better, then that's your OPINION AND PREFERENCE. That doesn't mean it's fact.
|
It’s the same speaker cone… it is absolutely in time. It is OK to have a subjective opinion, but an objective opinion should be based in reality and fact.
OK, use an EQ… then the FR is perfect. You had the post about time domain, and a IB is about as good as it gets in transcient response. |
I dont need you to tell me that. You need to convince @holmz Hes the one disputing that not me.
You cant EQ a cancellation can you?
We are talking OB not IB.
If it was in time, how can it be out of phase? |
@kenjit i agree for 100% , the open baffle desigh is made for folk who is looking for something unsual , The speaker bulders using old idea like new , Nothing magic . Depend of baffle size , sound wave from front cone meet wave from back and kill each other, The best open baffle is infinity size baffle. For size 20-25" you did not get low base, If you dont care about listen as is, If not --get sub , NO BENEFIT Placebo effect |
@kenjit Its apparent that there is something you don't understand. It has to do with the human ear/brain system. When the ear hears a sound, a copy of the sound is made and the ear/brain system looks for other examples in near-time. If it finds an example that is delayed by about 10 mS or so, it can use that for echo-location. If the rear firing information is about 5 feet from the wall behind the speaker, it will arrive at the listener about 10mS after the front wave. This is why speakers with rear firing information can have a more palpable sound stage. So time-alignment has nothing to do with it.
|
Bache says
Listen to the speaker designer folks. He agrees with me. |
I thought all speaker designers are wrong all of the time. You have been saying that over and over for years. I guess they are ok with if they agree with any of your random ideas. But he will be wrong, wrong, wrong, when he disagrees with one of your brain storms. |
@kenjit I need no convincing, his understanding seems on point. The OB may be out of polarity, but who cares in the upper freq ranges?
That may make the impulse response off of the wall negative, whereas it would hav been positive. It should show up there, but is that a problem? Many speakers have drives that are out of polarity with each other, and people like them… so how is OB different in the reflected back wave? |
If a box is unavoidable, it should definitely have the largest radius edges possible, and ideally the curvature should go all the way to the driver frame - like the concrete speakers I had once. Think those were made in some Scandinavian country - wish I could remember the name. Someone on A-gon probably knows this company. But I wasn’t referring to edge-diffraction (that’s a whole separate issue), I was talking of flat front baffle reflecting surface area (initial reflections allow acoustical localization).
Yes, to maximize ’disappearance’, surface area perpendicular to the listener should be minimized - like you said... narrow baffle. My GoldenEar Tritons are an example of this, also most KEF and many others including the Anthony Gallo Strada’s as an extreme example and the tweeter pods on most B&W - for that matter we all know what the B&W Nautilus looks like (all the same philosophy). Both of my above statements are witnessed in the KEF Blades and B&W Nautilus (extremely rounded and narrow-as-possible front baffles) - I count these as great designs (judged soly by their visual aspects).You can look at either of these and say, "Those are likely to disappear in a room" because of how they are shaped. Now, there are other factors that can draw attention to a speaker, like resonances, drivers sounding forward or unnaturally bright - but at least these designs have a shape that will allow greatness.
Yes, your correct in the statement, "...which could not be dealt with." Notice what SF have done to "deal with it"; front baffle narrow as the drivers will allow (does this sound familiar?), entire front baffle surface covered in (expensive) absorptive material, the front-baffle is also curved and the cabinet sidewalls are curved and form a triangular profile. I said in previous post of this thread, "...throw $ at it", and Sonus Faber exemplifies this method.
Also note that controlling reflections in a room can cover-up speaker localization too - I put that in the category of "throw $ at it". |
A lot of folks do care. Magico, Kef, B&W, Wilson Audio, Focal, Genelec, Revel, Unless you only like listening to upper freq range then its a big problem. Theres more closed box speakers than open. What do you gain by throwing the box away? you just LOSE all the bass. I dont see any advantages whatsoever. |
I switched to OB speakers (Emerald Physics) a while ago, and I don't think I could ever go back to a box speaker. They need lots of room to breathe and placement can be tricky, but they sound absolutely glorious when you get them dialed in. Anyone who tells you differently is talking out of their ass.
|
The best sound I’ve ever heard to date was the Nola Grand Reference open-back dynamic towers driven by top ARC electronics. You can say whatever you want about OB designs, but that sound will live with me forever, and if it’s wrong I don’t wanna be right. Just sayin’. Also, if you pluck an acoustic guitar in open space it seems to me the sound that travels backwards will be at least somewhat out of phase kinda like a dipole driver, and a non-dipole speaker greatly misses or greatly diminishes the backward sound projection that is projected by an actual instrument yet could be captured in a good recording. Could be wrong, but this makes intuitive sense to me. |
I've used B&W 804S speakers with their passive crossovers, then went active with digital xo, then into DIY boxed and eventually open baffle. Of course I do measurements for design work. System has now 2 sealed subs to 80Hz, 18" OB midbasses in H panel, and tweeter and midrange sitting above on a much slimmer panel. My tweeter is Beyma TPL-150H, which is actually the same one Spatial Audio uses on their X3 and X4, and I used to use it in a closed box and now open in the back. In fact, when I first ventured into OB I followed the back-to-front symmetry mantra and used a back waveguide like the one it has on the front and eventually realized it sounded as well without it so the back horn was removed (like Spatial does). The TPL is directly driven from Yamamoto 45-type SET...so much definition yet sweetness. The tweeter and midranges sound better to me in OB than boxed - same drivers - however I can easily compensate for the lower frequency decay in the mids, which is a natural phenomenon from the physics of drivers in OB. With passive XO this is trickier to get good results. There were comments about wide panels. Of course wide panels are needed to support the lower end. However for midranges the wide panel is an issue: above the dipole peak the response is all over the place, especially noticeable at varying angles from the center. Narrow baffles allow reaching higher without this issue, to the point some people use baffleless (been there and came back). Crossing over before the dipole peak is preferred. Spatial Audio, to keep the example above, doesn't do this. Never heard one, but tend to think this would be audible. Midbass is where I'm still not sure. OB definitely has more definition. However, even using 18" midbasses the sense of impact is much lighter than sealed. Maybe it's because I'm using a Faital driver that is not designed for OB and has low Qts, or because my room can't accommodate speakers 6 feet away from the front wall. I'm contemplating getting 15" Acoustic Elegance LO15, designed for OB, or a slot-loaded open baffle design that apparently conveys more impact while keeping the definition of OB. TBD. For subs I experimented a bit, exchanged with Danny Richie at GR Research, who developed OB subs with Rythmik, and concluded my room wasn't suitable for such subs. I'm getting two additional sealed Rythmik kits to have 4 sealed subs. Erik, I remember you at DIY Audio, so you probably have the skills and have fun building stuff. Would encourage you to do so, learn and listen for yourself. I have learnt some "laws" that are commonly accepted in audio fora that turned out not to be audible to me. Have fun! |
I’ve read some things in this thread that don’t jibe with my experience. I’ve had great box speakers that didn’t sound boxy. I now have Spatial Audio M3 Sapphires that are not forward and not harsh. I’ve driven them with a class d 2Cherry, an Orchard Audio GaN class d Stereo Ultra and a Wells class a/ b biased to 15 Watts class a… the speakers completely disappear with all 3 amps.
Im pretty sure there is no “better” in term of hearing… there is just preference…at any rate, open baffles are not inherently better or worse but it is absolutely possible to get very musical sound from them.
|
"i agree for 100% , the open baffle desigh is made for folk who is looking for something unsual , The speaker bulders using old idea like new , Nothing magic . Depend of baffle size , sound wave from front cone meet wave from back and kill each other, The best open baffle is infinity size baffle. For size 20-25" you did not get low base, If you dont care about listen as is, If not --get sub , NO BENEFIT Placebo effect" This shows a mis understandng of open baffle. If drivers were facing each other and fired toward each other, we clearly have cancellation. An open baffle fires forward Sound waves and they move forward. When the rear waves fire out of the rear, they are not directly battling the front wave causing cancellation. Ralph had the right idea. The rear waves take time to bounce off of rear or side walls and end up coming forward firing in the same direction and reinforcing the front wave, the front and rear waves do not meet head to head causing cancelation. What you get is a delayed effect for much of the frequency causing a spatial effect, which I assume is why a certain speaker company chose that name. The real challenge is moving enough air at low frequencies to produce satisfying bass.which can be done. |
Ok @kenjit you seem hung up on the back wave being opposite polarity from the front wave. Then in the other time domain thread you mentioned how all speakers were not right. is it more important that:
Magico - See figure 7:
Kef see the step function figure:
B&W:
Wilson Sasha (see figure 8):
Focal (see figure 5):
Genelec:
Revel - See figure 7:
|
With respect to my experience with dipole speakers, I agree completely - very well said!
I haven't found this to be the case with LXmini + Phoenix[alt] OB-subs; however, the only other OB-like dipole speaker I have experience with is Martin Logan e-stats, and they needed breathing room, critical placement and very limited listening position. The carioid/omni dispersion pattern eliminates those issues.
|
I purchased Spatial Audio X5 open baffle speakers about two years ago and can honestly say I will probably not go back to a box speaker. I belong to an audio club and have listened to multiple box speakers and some open baffle speakers at their homes and at audio shows and I simply prefer the sound of open baffles. Of course there are many box speakers that I've really enjoyed and also some open baffle speakers I did not. But in my opinion the way an open baffle projects the sound reminds me more of how live music sounds. And bass frequencies just sound faster and more detailed than most box speakers I've heard. The problem with the bass is not that it's coming from a box it's that most people's rooms have many bass resonances that are difficult to control. Box speakers excite all six room nodes while open baffles project a figure 8 pattern and only excites two nodes, the front and back walls. I was astonished how much cleaner the bass presentation was when i purchased my open baffles. Previously I had used some well regarded floor standers and monitors with subwoofers and could never get the quality of bass I'm getting now. Also the midrange sounds more open due to the lack of box effect/influence. It's true open baffle bass is not as powerful but in the case of the X5s the oversized woofer is self powered by a Class D amplifier which includes DSP and a level control. So I can adjust the bass exactly to suit my preference and room. I'm getting flat bass into the upper 20s which is more than sufficient for music listening and no longer use my subwoofers as they detract from the bass quality. If I ever move my system to a larger room I would maybe purchase open baffle subs if necessary. Nearly all of the audio club members who've listened to my speakers agree that they are special speakers and previously would have never even listened to an open baffle speaker due to previous misconceptions. A few have already purchased them. It's true you do need at least three feet distance from the front wall but I've also had any of my previous box speakers at least that far away from the front wall and usually further out than that. I have a difficult room in a basement and have very little need for my room treatments any longer as well although I've kept some on the front wall for diffusion. |
Yes I do believe that the back wave needs to be in correct polarity as front. As you know, aboslute polarity is inaudible but with an open baffle, you have both waves occuring simultaneously. It is difficult to avoid the consequent cancellations unless you physically separate the two waves. That is the whole point of having a box. |
That sounds a bit like a Helmholz radiator?
I doubt it would be a hoot. A debate is not just about being impassioned about the topic.
You kinda cannot have it both ways… where you:
I mean you can argue that, it is just hard to abide it as a rational argument that is anything more than “Like your opinion dude.” |
| Post removed |
@erik_squires I attracted a ban on another form overnight. And there is no honest way to comment on the Scooby-Doo without attracting a ban. And I cannot send a MSG on AG, as I get an endless “Q&A” to identify as a person with hot air balloons… crosswalks and traffic lights.
Let;s just say it is baffleing |
You can't be serious. 99% of high end speaker designs are NOT open baffle they are boxes. They are all on my side. I have already named many of them. B&W, KEF, FOCAL, DYNAUDIO, MAGICO, WILSON. |
| Post removed |
Steve Guttenberg Audiophiliac has changed his reference speaker form horns to open baffle. His explanation about why mirrors what most are saying about the open baffle. Hifi Cave guy is enamored with the Liionidas EXTREME OPEN BAFFLES Bass was not an issue for him. These speaker actually exposed his lack of construction ability and rattled his room treatments. The main question is that can you dedicate the space that open baffles require? The going consensus is that they sound better at a minimum three feet from the wall.
|
@twoleftears For those interested, that track was Birds by Dominique Fils-Aimé from the album Nameless. Nice track.
|
Infinite baffle is just different. Its what most high end studios use (though they’ll often call it “flush mounted” or “soffit mounted”) Of course this is for music creation not home “recreation” for enjoyment. Most music studios don’t want extra ambience from added ambient reflections which most audiophiles enjoy. They need to focus on the unaltered sound so as to know what to do to thier mix. Thats generally for both tracking and mastering …… |
@kenjit , I invite you to come on over and hear what I’m hearing from my OB setup. You don’t have, nor have you ever heard a pair of properly set up OB speakers, have you? Your ignorance is monumental, and it’s showing. Might want to slow your roll.... You couldn’t possibly be wrong, could you? No, everyone else posting in here is clueless, and you know everything there is to know about speaker design, lol. This place cracks me up. You’re not here to learn anything, you’re here to jam your mis-founded beliefs down people’s throats. Behold: The Idiot Savant. Or is that.....just the village Idiot?
|
Back to our scheduled programming…
|
@kenjit So, I’d love to hear you tell Richard Vandersteen, Carl Marchisotto, Jim Winey, Dr. Roger West and Dr. Dale Ream, and Gayle Sanders among others why they’re wrong. That would indeed be fun. I’m sure your IQ and experience is superior to these misled speaker manufacturers, so it’d be really fun to hear you correct them and put them in their place. Troll City. Population you.
|
It is really sad to see more and more dogmatists spoiling this forum, which I thought was meant to create an easy way to exchange our experiences: EXPERIENCES, not theoretical arguments. In case of the open baffle loudspeakers and the voiced criticism that the back-aiming sound wave is out of phase (probably correct) one concludes that because of this, they are "wrong". This sounds almost like evangelical argumentation. My point would be, that all music, lest the one played back in a recording studio, is "out of phase". Case in point: a symphony orchestra. It is usually stacked 15 meters back or even more (in case of the Mahler orchestra) and often also lifted towards the back by several feet. While playing the same theme, the sound from the 1st and 2nd violin strings will arrive earlier at the orchestra seat than the woodwinds, and the brass even with more delay. Guess what? Our brains accommodate for this with delight, as it gives it all the spacial clues it needs to relax and enjoy: it's called "psycho-acoustics", and the late Herbert von Karajan endowed a continuing research grant to explore and correctly describe it's effects. Our ears are not oscilloscopes! Which brings me to my actual contribution: I am totally in love with my Linkwitz LX521 speakers (https://linkwitz.store/category/lxspeakers/), powered by Dr. Frank Brenner's active analog 4-channel signal-processor/amplifier system (same URL "PowerBox 6pro NCore Precision Analog"). I had listened to Siegfried Linkwtz's original Orion speakers at several audio shows, and was blown away. At the 2006 RMAF I was about to buy them, when Siegfried's wife told me that he was working on an even better design (in a report of the event STEREOPHILE gave the Linkwitz room "best-in-show", btw). Then, at the 2012 Burning Amp (if I remember correctly) the LX 521 was shown (with passive crossover and powered by 4 PASS LABS amps): Nelson Pass had set up the display himself (he and Siegfried were long time friends; and yes: Nelson uses this open baffle system himself, apparently even while it's "wrong"). That's when I made the plunge: I ordered the construction materials and SEAS speaker sets from Dr. Brenner (the pre-cut birchwood ply panels need to be glued together and internally wired, which is actually a lot of fun) and after a few weeks, I gave the raw chassis to my local MAACO paint shop to have them painted in Lexus Pearl White with extra glitter. You can look at them here (before they moved into the music room): https://linkwitzlab.com/LX521/PhotoGallery.htm (mine are the white ones, 5th entry from the top). And then the magic happened: once properly placed (4 feet from the back (which is actually our terrace sliding door) and 3 feet from each side wall, the musical event unfolds between the speakers and somewhat behind them: one seems to "look" onto a virtual stage, whether it is solo voice (Maria Callas, Lyle Lovett, or Boz Scaggs), string quartet (Bush Quartett EMI C147-01668/70), or Steely Dan, jazz piano (Oscar Peterson "We get Requests"), or Mahler #2 (Klemperer, ERC). Most remarkably: there is no sweet spot! I can move mack and forward, stand up and even go to the back of the room: the musical event is firmly locked between the speakers and stays focused, unlike the MBL Radialstrahlers which fill the room with sound that is omni-directional. In fact, if I open the terrace door, Maria Callas seems to sing on the terrace as if she was standing in front of the pool. Unreal! In conclusion: On his website, the late Siegfried Linkwitz (we became friends towards the end of his life) gives everyone an in-depth primer about psycho acoustics and how this discipline has influenced the design of his incomparable speakers, and Dr. Brenner is carrying on the legacy by providing future-proof support electronics which make the magic happen: and all that for a price less than a Lyra Atlas cartridge! [ProJect LP10 Carbon TT with Benz Micro LPS; MSB Platinum V Signature CD player/DAC; Supratek Grange Preamp; Linkwitz 6Pro NCore analog data processing/power amp; Linkwitz LX521 4-way active speakers] |
@johnnycamp5 wrote: "We read in this thread a redundant dimension of about 3’ off front wall as a minimum with OB. "I wonder if less distance (approx. 2’) with heavy drapes behind might work…" Not really. Imo the issue is time delay, and you can’t get 3 feet worth of time delay with 2 feet plus heavy drapes. Also a benefit of many open-baffle speakers is that the backwave has essentially the same spectral balance as the frontwave, and heavy drapes would selectively attenuate the short wavelengths (high frequencies), degrading the spectral balance of the backwave. |
It is not that sad… (And I am only a dogmatist about woofers.)
“Reversed polarity” is probably better than “out of phase.” In any case a box speaker have very little back wave, and if it has a port there is not much back wave except near the post freq. If having a back wave with the opposite polarity is bad, then a dipole should be really bad, because the back wave is many dB higher than anything sneaking around a closed box. |
The closer the OB is to the front wall, the higher the cancellation that between front and back wave, and the shorter the time difference in arrival times between the direct and reflected sound (per Ralph's post above). So further away from the way is better for both how low end reach and the sense of envelopment. Linkwitz recommended a reflective front wall, which happened to be what he had at home. I happened to have a treated room with absorbent front wall and can get my speakers 3 feet away from the front wall, and I'm happy with the sound. Maybe I would be happier with a reflective wall? Dunno. The midbass, as noted, lacks some impact even though it's 18", have a dedicated Hypex class-D directly powering it and it's adjusted to measure flat...yet the sense of impact is different in my case. |
Thanks @audiokinesis I should be more specific- Are all OB open back tweeter? I thought some had forward only directivity . So the heavy drapes question was more for the mid range and bass frequencies. @invalid your comment about sounding best at 7’ off front wall is always why these types of loudspeakers (dipole) are “non starters” for me. I just can’t kill a whole room with that kind of placement. I have a 21’x22’ garage I’m completing mostly for stereo and media…and Still these distances are unacceptable to me. I’m sure it’s why I’ve always been attracted to horns for their controlled directivity. But man that open spacious sound of OB is hard to beat if set up right…just a whole different flavor of goodness. I suppose I could move the OB’s back-and-forth all the time for use…but what a BS hassle… |
Not all OB have open back tweeters. The Spatial audio x series have open back tweeters and their M series do not. If you cannot have about three feet from the front wall then a powered open baffle such as the X series and other open baffle speakers that have powered controllable woofers would make sense as you could increase or control the bass quantity to match your speaker location. Sure if the speakers are only two feet from the front wall you would probably also lose a bit of spaciousness as compared to at least 3 feet. |
Hey @emrofsemanon You have it mostly right... an "infinite baffle" is a situation where you have a theoretical infinite width and height wall on which the drivers are mounted. The open baffle uses both the rear reflection but also the nulls to the sides. The idea is that you get less side reflections, but also quite a bit of ambience which can help improve imaging from the rear. |
