DIY Open Baffle Info Needed

With most OB using 12" & 15" woofers, the base might sound OK in the nearfield.
Now I've learned to use this reply feature properly!

So your speakers and their shortcomings can reflect what kind of listener you are; I'm of the classic "Memorex poster" style. I really dont expect them to sound all that great outside of that envelope; a couple butts wide on the nearfield placed sofa chair. Even uniformly dispersive speakers, because now that they sound substantially the same everywhere you are, the room walls hear it uniformly loud too and so on.

I know I've seen OB with horns - the "PAP Trio 15 Horn1"! A D'Appolito arrangement. While the horn doesnt radiate backward of course, the above and below drivers do, up to the crossover point. I figure there must be something to it, for someone to build and market 'em like that. Would those get you another 15-20% of the way there, just because of the horn and compression driver used? With only the nearfield bass limitation as an anomaly?

I think these (https://theaudiophileman.com/spatial/) are OBs with horns, that do radiate backward as well... At $14k / pair, I'm quite likely not about to personally find out where they rank.
 
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Quite, but conceptually a doddle to DIY. The expensive bit is getting a compression mid-tweet that can get down as low as the one used in the X1. That's not cheap. Neither is the 18in AE woofer, but while you can get a range of more affordable 18in drivers, said midtweet is a bit harder. Otherwise -thick flat baffle, woofer, compression unit & horn. If you're willing to cross a bit higher, plenty more relatively affordable off-the-shelf options available.

An inexpensive approximate equivalent from the POV of polars would be to run a dipole woofer with a decent wideband as the midtweet, the latter in a sealed box so it's operating as a monopole, and in either case, your choice of digital XO and filter.
 
You are obviously terribly frustrated that you failed to build proper ob bass.

You are obviously terribly frustrated that you failed to build proper ob bass.
Commenting about a commenter is a looserish thing to do, especially since you do not know me or anything about me the way I do not know and frankly do not care to know anything about you. So, do stick to the subject matter at hand before my opinion that you are not particularly bright has hardened into certainty...
 
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With most OB using 12" & 15" woofers, the base might sound OK in the nearfield. But if you were planning to enjoy your music from across the room, well, tough luck!
That's true only if the OB bass isn't done right. And I've heard too many like that, OB bass isn't as easy to get right as box bass. Once you understand the limitations of OB bass, then the design can go in right direction. It took me over a year to figure it out, and I had help!

A week ago I took a pair of well known OB speakers into a rather large space and sat 18-20 feet away. There was too much bass and not enough treble. Because there is so much energy coming out the the back of an OB, the room and room placement can make significant difference.
 
It seems counterproductive to badmouth ob in an ob thread.
The person who started this thread stated that he does speakers for fun, as it should be.
Then comes a dour and overly serious yourself, trying to police other people's comments.
If you got nothing of your own to contribute in a meaningful way, then just sit back and read other's comments, you might even learn a thing or two. But do not offer these "short farts into water", trying to make it splash....
 
Indeed, an OB is a dipole speaker system, and after having done a couple that sounded allright, I still switched to making boxes - simply because of their flexibility of placement. I decided I did not like the speakers to be the boss and dictate things in my own home, making me compromise on other things. I also own a piano and some other instruments, but even placement of those is less demanding than OB's.

This reminds me of a French Mr. Salabert (hope spelled his name right) who passed away many years ago but founded a Phy-HP and made the most unique wide-band drivers by hand. (Whoever own it now and makes his drivers - I've heard they are much worse now). Anyways, he designed the most amazing wide-band driver without a wheezer cone, and yet, he designed it on its own in near-field laying on the table, without any enclosure in mind, and for the rest of his life could not find the right enclosure for it! He tried everything - a large OB, a folded OB, fully enclosed box, transmission line, etc.

The most difficult concept for any DIY to accept is that the speakers comprise a system, i.e. it is not only about the drivers or about an enclosure, or about a crossover, but about all of these parts working in unison producing something greater than each part on its own...
 
Now I've learned to use this reply feature properly!

So your speakers and their shortcomings can reflect what kind of listener you are; I'm of the classic "Memorex poster" style. I really dont expect them to sound all that great outside of that envelope; a couple butts wide on the nearfield placed sofa chair. Even uniformly dispersive speakers, because now that they sound substantially the same everywhere you are, the room walls hear it uniformly loud too and so on.

I know I've seen OB with horns - the "PAP Trio 15 Horn1"! A D'Appolito arrangement. While the horn doesnt radiate backward of course, the above and below drivers do, up to the crossover point. I figure there must be something to it, for someone to build and market 'em like that. Would those get you another 15-20% of the way there, just because of the horn and compression driver used? With only the nearfield bass limitation as an anomaly?

I think these (https://theaudiophileman.com/spatial/) are OBs with horns, that do radiate backward as well... At $14k / pair, I'm quite likely not about to personally find out where they rank.
Well implemented horns do sound best in my experience, but it is tricky to do them right- probably the trickiest system of all. The drivers are the most exotic most complex to make and expensive, the horns themselves are difficult to calculate and to properly make, but none of it is frankly the point. I admit, there is a certain mystery to this, as I do not know if anyone figured out as to why one type of transducer sounds so much closer to live music than any other type. I read somewhere it may have something to do with the wavefront shape that to our ears appears more 'natural'...

I used to read a lot, but only on rare occasions I encountered what I believed a true insight into why things might be the way they are: - For example, in an old article by Art Dudley whose viewpoint and writing I really liked, he explained why he thought turntable sounded most life-like from all source components: - Because stylus and the spinning vinyl disk formed an electric generator, so turntable signal is truly and fully "generated" from scratch, as opposed to having to piggy-back onto an already pre-supplied current as happens in every other source component! He believed that this purity of signal was precisely what made turntables sound most realistic of all sources. Yes, the clicks were part of the signal, that is why some find it less objectionable than say digital flutter in DAC's... When I read that, it made total sense to me, so I believed it.

Have not read yet anything of the sort about why horns or any other speaker type should present the most live-like sound. But my ears do tell me horns are best, and, for now, it is enough. Besides, horns are difficult to design and implement, and when not done right, they become squawky and can sound horrible.

As to combining horn and OB - those things were done many times before, though some "horny" peeps (haha) think with horns you do not need any OB at all, a frame is sufficient to hold it up, just like in OMA Imperia:
1642601278842.png
These use conical horns which are most hardcore, most archaic, and to horn zealots, least compromised and most pure-sounding...

Lastly, I do not advocate for making horns. Making boxes was difficult enough for me. Also, I do not live in a former warehouse and do not own a private cinema to place those in...

I think a good OB will get you 75% "there"; I also think for majority of folks that would be sufficient...
Great boxes will get you 85% there. Good horns will take you 90% there.

If you want a 100% - get a proper instrument, be it a piano, a guitar or a violin, learn to play it, and enjoy live music in room whenever you desire.
Cheers!
 
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music soothes the savage beast
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Commenting about a commenter is a looserish thing to do, especially since you do not know me or anything about me the way I do not know and frankly do not care to know anything about you. So, do stick to the subject matter at hand before my opinion that you are not particularly bright has hardened into certainty...
I am very happy with the quality of my OB bass, if done right, can sound nothing like you described. So I know now for sure you never heard proper OB bass.
 
I like building HiFi speakers. Recently I became enthralled with the concept of open baffle. Where can I find concise information on what specifications I should be looking for with regards to a 10" or 12" full range or coaxial driver? Any recommendations for drivers around $150 each? Are there any online DIY plans or websites I should be looking at? Thanks in advance!
Before bowing out of this thread for good, I decided to share a couple of OB things I found most useful in my days of making OB’s (which ended about five years ago):

My most effective OB was a copy of Nelson’s Pass OB with a “slot-loaded” woofer. It was a very popular design at the time (around 2010-2012) and a few people in this community did this type of OB’s, because it works and works rather well. If you search, you can still find the actual dimensional drawing and instructions as to how to make it – there is still a thread in this community that I myself used to consult a lot:
https://www.diyaudio.com/community/...slot-loaded-open-baffle-project.195734/page-6
(FYI - for the mid driver I personally used and still love the sound of legendary Supravox RTF drivers – Supravox still makes great drivers, and you can find them if you search)

For those who are interested in how the principle of “velocity loading” works, there is a short article penned by Nelson Pass on this subject, going to try to attach it to this post. It is informative for anyone interested in OB’s.

Lastly, once I understood, or rather, arrived at the inherent limitations of OB’s, and decided that I did not wish to put up with their placement issues, AND knowing the intrinsic superiority of horns, yet knowing that horns were not for me as I did not own a former cinema theater to place them in, there was still one hybrid system that combined OB and horns that I really wanted to build some day, but have not got around to doing it yet. Some dudes in upper NY state make it based on original French design (most "hornies" are typically obsessed with WE/RCA stuff, but French were good at it too)
1642604857730.png

For more info, read the article from October 2018 Stereophile magazine written by the now unfortunately diseased Art Dudley. I actually pretty much stopped reading the magazine after his passing, as it became yet another “meh” mag. Here's the link:
https://www.stereophile.com/content/listening-190-experience-music
Cheers and good luck to all in pursuit of OB’s!
 

Attachments

  • Pass Slot Loading.pdf
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music soothes the savage beast
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In the main system I do use four 15" woofers, two per side, one after another, like emerald physics, but with bridge over, to serve as stand for midbass and up. I used to have web page describing my dipole bass, but is was on geocities and was taken down. I have ultracurve to eq flat in my listening position, so I do not have any lack of bass, since its flat all the way to 20Hz.
I do not listen very loud (75-85dB), but occasionally have friends over, and we do crank it up. Bass is always clean, precise, no matter what level.

I do have three other systems, two of which have closed box woofers, utilizing the same 15" woofer, but the quality of bass is not there. OB done well, the bass is accurate and free of any boominess (or boxiness), for lack of better word.
One more thing, steeper slope is used for active crossover for sub then for midbass and up. Since I use midbass on open baffle too, natural roll off and first order crossover is enough. However, for sub, that is not enough, I cross much steeper.
 
I am very happy with the quality of my OB bass, if done right, can sound nothing like you described. So I know now for sure you never heard proper OB bass.
You seem to know so much about me, all of it from my one post.

BTW, everyone was so curious about YOUR bass! Knowing nothing else about it, but I am glad you like it! I do know that if you were to move to a bigger house with a bigger listening room, your current bass may not suffice.... (Which is the case with pretty much everyone)

Now, on the more serious tone, you must be one of those strange fellas who got to try-on every comment onto themselves, otherwise I guess you simply cannot otherwise process it: - if something is good to YOU, it absolutely MUST be good for EVERYONE else! And if someone disagrees, well, how dare they? Right? RIGHT??!
 
In the main system I do use four 15" woofers, two per side, one after another, like emerald physics, but with bridge over, to serve as stand for midbass and up. I used to have web page describing my dipole bass, but is was on geocities and was taken down. I have ultracurve to eq flat in my listening position, so I do not have any lack of bass, since its flat all the way to 20Hz.
I do not listen very loud (75-85dB), but occasionally have friends over, and we do crank it up. Bass is always clean, precise, no matter what level.

I do have three other systems, two of which have closed box woofers, utilizing the same 15" woofer, but the quality of bass is not there. OB done well, the bass is accurate and free of any boominess (or boxiness), for lack of better word.
One more thing, steeper slope is used for active crossover for sub then for midbass and up. Since I use midbass on open baffle too, natural roll off and first order crossover is enough. However, for sub, that is not enough, I cross much steeper.
Oh, wow, there is actual info here! Wish you shared it before your other nasty shorty of a comment.
BTW, for boxes to sound good, they need to be well implemented too! Not sure what boxes you are using that you were referring to as inferior to OB. Maybe they are...

Anyways, I attached a Nelson Pass article on "slot-loading" for OB's in one of my other posts. He goes into detail and theory of "velocity-loading" as it is frequently called, which for years (since 2011 or so) was used many times by many other members here to mitigate the naturally "sucky" bass of OB's.
(FYI - I am a purist of sorts, and do not like pairing normal "subs" with OB's.)
Cheers!
 
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Well you did say this:
With most OB using 12" & 15" woofers, the base might sound OK in the nearfield. But if you were planning to enjoy your music from across the room, well, tough luck!
Which is not my experience at all, so I take exception to the statement. It seems that other do too, because their experience does fit with your statement.
The lack of bass across the room might well be your experience, but it is not at all for many us. Perhaps we are just lucky. :)
 
Well you did say this:

Which is not my experience at all, so I take exception to the statement. It seems that other do too, because their experience does fit with your statement.
The lack of bass across the room might well be your experience, but it is not at all for many us. Perhaps we are just lucky. :)
I agree, I did not articulate it right the first time 'round. You do get bass (bass is actually the easiest to get anywhere), but it is the integration between all the audio bands that becomes muddied and no longer "of the piece" once you start stepping into the room.
I guess I meant to say that fidelity of overall sound deteriorates. OB's tend to work OK in nearfield, but their dipole nature catches up with them as you step away. Mostly because of reflections, but also because of the bass "loading" issues into the room. Hope this clarifies it.
 
BTW- the second video shows Tannoy Kensington which are about $15k/pair
Those box speakers sound like a box resonating to me. Well done OB in the right room sound so much better to me. For DIY OB also have advantages in build cost and time. Everyone to their own. Vive la différence.....
Here is a quick scan of the inexpensive OB speakers I built......I was surprised how good it was. Using a B&W subwoofer at 150Hz they really sound good.
That was a quick build! Smart to use your existing closed subs under 150Hz. What OB design did you go for? Are there pictures somewhere please?
 
What OB design did you go for? Are there pictures somewhere please?
Well, to be honest, zero design. I just bought a piece of 24X48 Bambo plywood. Decided on 18X24" so I'd have some left over for the stands. Cut a hole in the middle and mounted the Tang Band drivers I removed from a previous build.......That's it! Not very scientific, but I'm listening to them as I type this and they really do sound good!
 
Whats the imaging like compared the KEF's?
I have to start answering this question by saying, NOTHING compares to the LS50 Metas when is comes to imaging and sound stage...NOTHING! I've been in the HiFi business for over 40 years, have auditioned hundreds of higher end loudspeakers, an none have impressed me with the imaging of the LS50 Metas. So that said, they don't compare at all....BUT, they do compare with other speakers I have....B&W DM601, Klipsch RP600m, ELAC 2.0/6.5 and others....And they image as good if not better that all those listed.....Depth of field is fantastic as is vocal position. Considering we are talking about a $79 driver mounted to a piece of plywood with no other associated electrical components....They are truly amazing!