The REAL Reason Why Open Baffle Sounds Better Than Box Speakers

READ ME! My opinion, after thinking on it long and hard and listening to my own open baffle speakers for 2 years is that the main difference is the midrange presentation. The open mid projects the sound back out of phase with the front output and reflects off the wall behind the speaker. It then combines (largely in phase) with the front output and changes what you'd get from the front firing driver. So, in a boxed speaker you only get that front firing sound, while the dipole gives you that PLUS the reflected back firing output as well. That changes the character of the sound and gives open baffle its distinctive sound quality. Is is perfectly accurate? No, obviously not, but that really doesn't matter. You either like it or you don't, and that's what's important. Now I will say that unless you've actually tried listening to a well designed pair of open baffle speakers, you can't have an opinion either way. I think most who do start listening to OB don't go back to boxed speakers. At least not willingly - maybe their situation changed and they need to listen in closer quarters where the speakers must be too close to the front wall to realize the benefits of OB. I used the term ethereal to describe the sound difference because it's the word that came to mind, but maybe a better way to describe the OB is to say more expansive. As in it projects a bigger sonic presentation, but retains pinpoint imaging and immersive soundstage. In my latest OB design: https://youtu.be/PuQhntQwjpM I focused on the midrange driver with these conclusions in mind. The bass is omnidirectional for all speaker types, and the tweeter doesn't carry enough of the music spectrum (there's very little content above 10KHz in most music) to warrant making it rear firing as well. Whereas the mid carries the bulk of what serious listeners are looking for in a refined and engaging listening experience. My design lets the high efficiency mid play a wide range of the audio spectrum and is run through a 1st order bandpass filter to extend that coverage down into the low midrange and up into the treble.

“Great minds discuss ideas. Average minds discuss events. Small minds discuss people.” ― Henry Thomas Buckle

Thanks for the di-pole discussion. It reminded me of the properties of a bi-directional mic, and gave me a better way of thinking about open baffle speakers

Cool info! Back in college, I was planning to build an open baffle speaker I read about in Speaker Builder magazine. I bought two Realistic speakers and cut out the cones... then glued plastic soda bottle caps to drive a large Mylar baffles. The top of the baffle had Seas midranges (with the clear blue dust caps) and the design called for front and rear firing 3/4" dome tweeters. Unfortunately, I never got around to building the crossovers.

I really enjoy a large soundstage and good imaging. For me, my OB speakers excel even in a small room.

I've got a set of mirage om12's, listening to you explain how the sound is more full I can relate, the sound is beautiful compared to a normal boxed speaker

John great job. I would be very interested in your design not sure I need you to manufacture the speakers but maybe sell them as a kit with baffle or without. Will your design work very well if placed 16" from a back wall?

Could you do a video on omnidirectional speakers? I heard a Walsh Ohm recently and it was amazing. I'd like to know whether there's a big difference with the dipoles. Another question - instruments and vocals vary a lot in terms of omnidirectional vs directional. Strings are omnidirectional, but brass instruments are more unidirectional. How well do different speaker types reproduce these sounds?

Hmm, I'll have to try a few open baffle design speakers myself then, because by what you're describing, it sounds like I would really like their sound presentation especially with already "ethereal" sounding music like a band called "Hooverphonic", of which I absolutely LOVE, and their first two albums especially would probably be absolutely spine tinglingly awesome on good open baffle speakers! (Their albums "A New Stereophonic Sound Spectacular" and "Blue Wonder Power Milk")

This is a great breakdown. Thanks John!

Thank you very much for the info. How about an audio system with 4 speakers. The ones behind or placed sideways. Should they be closed box?

My bedroom has a large walk-in closet, and on the other side of the closet is my listening room. So I just mounted the drivers on the wall of the closet. Is this setup a box speaker or an open baffle speaker? They do sound very good though. Getting the reflection from the back wall and mixing it up with the sound wave from the front is tricky. On certain frequencies, the waves cancel and that depends on the distance how far the speakers are from the back wall. The further away, the less the cancelation since the energy of waves reduces with the square of the distance. So the closer the listener is to the speakers, the less the cancelation.

Hi John, I am intrigued by your theory that the "open baffle magic" can be attributed to the backfiring midrange driver. Now, I just ordered a set of full range drivers for an open baffle setup, but I wonder if I am going to miss out on the magic. I mean, I suppose that only the woofer section of the full range will be backfiring, or are all the constituent frequencies coming through at the back?

Kind of reminds me of a time in the 1960’s where speakers were fitted into solid walls to provide an infinite baffle. The only sound was that created by the front of the speaker cone and the wall was open at the rear so there was no restriction at the rear of the speaker. In theory the perfect set up. The reality was that the lack of any rear reflection made the systems sound flat and uninteresting. Sound needs to be tailored to a room and personal preferences and a technically inferior system can sound absolutely great when properly set up, compared to a top spec system that is just dumped up against a wall.

With regards to the elusive combination of transparency and imaging, have you heard any large-woofer Tannoy dual concentric speakers? If so, how do they compare in your estimation to open-baffle?

John, how do you handle phase issues in a three way, open baffle speaker? That is, the physical distance placement between the drivers on the baffle itself? I assume the phase issues occur mostly at the crossover regions. Thanks...

Just digesting your description and I am imagining a skeletonised cabinet. Would this find a mid ground of the two deciples while being able to mitigate the sound field you desire. I enjoy the open but a tight acurate base with no port is nice.

When a musical instrument is being played in a room, you hear the sound from the instrument as well as the sound of the instrument bouncing off the back wall. An open baffle midrange does basically the same thing.

Hi John, I would buy your plans for your open baffle speakers. I have owned Magnepan.7i,1.7i,and now have LRS, which I am selling because I never listen to them because of the Klipsch La Scala’s in the room. I am a wood builder as opposed to being a wood worker. To me a wood worker is someone who loves to work with wood, a wood builder, like myself, builds cabinets, boxes, doors, ect. because of the economics and enjoyment of DIY but not obsessed in perfection. Any way, I enjoy your channel and I would buy the plans. I think a cone driver is more effective than a panel in moving air!

I had an open baffle build with Lii W15's and F15's. The effect you described was 100% present in my golden ratio room with dirac room correction and minimal room treatment. It's wild to experience open baffle for the first time. It won't be for everyone, but it definitely works for me.