Ultimate Open Baffle Gallery

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I don't know much about speaker theory. If IB means infinite baffle, my setup is probably IB rather than OB. My preference for OB mainly comes from its natural sound which is, I'm sure, brought by no pressure on the backside of the woofer cone. From such viewpoint, IB and OB are the same categories for me. Sealed enclosures are not. Quasi IB by an adjoining room is better than OB which has an inherent lack of bass. You can have an additional boost on bass by multi speakers. Four speakers is excellent to achieve natural bass. It can act as equalizer from 150Hz where each speaker becomes to have the same phase while more than 150Hz is at random(no boost occurs). If you are a carpenter, you can utilize an adjoining room and build a large room which is necessary for multi speakers. An electric engineer(it's me) totally can't overcome a carpenter in SQ. :eek:
 

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I've had my fun with the Van Halen planar dynamic hybrids, but was missing the transient snap of my horns.
Plundered my Onken cabinets, and am trying no baffle for now, as the Van Halens can be modded for a slob sub.
So far so good; the 2 Celestions are quite good without a baffle, as long as they're close together.
This pic was from this morning, prior to me mucking things up with wire.
I may post if I figure a way to do that neatly.
Maybe the easiest build I've ever done, and I think the no stain no oil no finish gets the steampunkish mancavd look I was aiming for.
Loving the exaggerated dynamics and colourations. The BG stuff is great, but horns are the fun date.

Pretty happy with this design, so I bought some nice Acacia lumber,to redo the open frame.
I realized I have 4 four ohm and 2 eight ohm 1525e in house, so now the upper woofers are 8 ohms,wired in parallel with 2 series wired 4 ohm woofers,which are bolted together,clamshell.
Things are a little bit cleaner sounding, and the soundstage more 3D like this
The remaining two 1543 woofers will be for distributed deep bass , in one or two existing Onken cabinets.
Putting the clamshell-isobaric in ruined the blend with my old Polk or diy Dayton RSS 265HF-4 Subwoofers.
Pics next week, with the new frames.
 
Just some experiments I did on OB :)

I did the Leonidas XO for PAP and try to test as many FR drivers as possible.

Also tried many 15 , 12 , 10 inch woofers.

After over 50 years diy speakers , OB is , for me , the way to go !!

Hope you all have fun and.......enjoy the music :)

Leon
 

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Here's the current incarnation of my hybrid speakers: OB bass + point source coaxial mid-high. It might inspire someone looking for a high-WAF OB (at least my wife is happy..)

I've got the idea to use the KEF HTS3001 sattelites from Patrick Bateman in the snytrip thread - takin the opportunity to thank him here ! The UniQ coaxial is really, really good and clean. I believe combining them with OB bass is a very effective way to get a great sounding speaker.

Some technical details:
- OB is Eminence Beta 15A in a "wedge"/Y baffle, helped by Graham Maynard's (RIP) T-Bass circuit published on this forum
- crossover at ~250 Hz LR2 (miniDSP) + room EQ

The KEF coaxials are replacing my Visaton 6xFRS8 + NEO3 PDR array panels (OB). As with most things in engineering, this is a step down in terms of naturalness and authority of vocals, but a step up in terms of imaging and resolution (plus much smaller size). At the moment I am happy with the result.
 

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Thanks !

But, if you are already using the miniDSP, why do you need the T-Bass circuit?

This has been a long and heated debate in the original T-Bass thread, with Graham arguing that T-Bass does something you cannot do with EQ alone, namely compensating the time-domain transient response of the large woofer + amplifier combo. The details are in 'T'-bass drive for OB LF drivers.

Personally, I do feel that there is somethig audible to it, so I'm using it together with miniDSP.
 
Bzfcocon do you have a schematic or some values for your T-bass circuit?

The schematic is on the first page of the thread. For the Beta 15As I use the following values:
L = 6.8 ohm, 0.26 ohm ferrite core
R1, R1 = 1 ohm
C = 330uF (bipolar) - I am cutting higher
Transformes are toroids, 250 VA 2x 18V (only the secondary is used)

I don't use the low pass filter on the right part of the schematic - that is optional and can be replaced by DSP/crossover.

Warning: you MUST use a 4 ohm capable amplifier. The impedance of the assembly is low. But it does not have to be an expesive one and you don't need a lot of power: with OB you typically run out of Xmax long before you run out of power. I'm using a good old HK 620 and it does the job just great (even at somewhat higher SPLs)
 
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Current and fourth setup after almost four years playing around with open baffle. Line Array Dipole with Corner Woofer. Satisfied for now but final? You never know...

Dipol Width
Dipolplus - Alles über offene Schallwände

Sparse line array
So gehts: Line-Array dimensionieren - Visaton Diskussionsforum
Golomb ruler - Wikipedia

Corner dipole woofer
Corner Dipole Woofer (CDW): info? anyone tried one?

Linearray
8 x Visaton SL7.13
SL 713 - 4 Ohm | Visaton
No power or frequency tapering
Baffle 1840 x 80 x 5 mm - Steel

Corner Woofer
OmnesAudio OBW1506 - 15inch open baffle woofer
8 ohm Qts 1.0, Xmax 12 mm, Sd 835 cm2
Baffle 600 x 600 x 28 mm - Solid beech glued

Active Crossover
Woofer Line Array X-over at 250Hz
Reckhorn DSP-6
https://reckhorn.com/frequenzweichen/139/dsp-6-digitale-frequenzweiche
 

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Open Frame speaker

Finally had time to finish these, excepting a grill. I'm leaning towards a string one, similar in principle to the Sonus Faber looks. The wood is Acacia, oiled, with a Peerless compression driver in a 511B Altec Lansing horn.
Woofers are Celestion 1525e .
Active crossovers, 1800, and 80 hertz for now, to a sealed 1ft3 cabinet, with a Dayton RSS265HF-4.
Assembling another sub, identical, because 80 hertz is a little low to fill the no baffle bass limits of the 15" woofers.
100-120 hertz sounds much better, but makes the sub easily locatable.
 

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MIT

Would it not be better to invest in some woofers with a larger Xmax?

The Celestion 1525e has only +/- 3.25 mm

Thanks, but I've been a fan of sub sat combos since I had the S100B/V125 Miller Kreisel pairings decades ago.
My intent here is controlled directivity, with dipoles and horns, along with placing the bass transducers where they sound best. In my room, that puts the sub in a front corner, and the satellites about 3 feet from the sidewalls, and about 5 feet from the front wall.
The other objectives are high efficiency for the satellites, to go with my baby class a amps, about 10 watts a channel, and the lowered Doppler distortion that comes with low excursion woofers.
So far so good.
 
Higher, lower, or sideways?

I'm again trying a 4 way.
Three way active crossovers, and now passively splitting the treble at 6500 Hz, Solen Split.
Using a JBL Selenium midrange allows a lower crossover point, to the woofers, so far 800 Hz is working well, with an improved smoothness , over the Peerless crossing near its lower limits, and the Celestions crossing near their upper limits.
I think they look better with 2 horns per channel, too.
 

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Hello ,
here is my open baffle project . 24 zoll Fane "Colossus" , JBL 2360 with BMS coaxial drivers . For mid and high I use single ended amps with RE604 and E406N and EL86 push pull for the bass . The active crossover is from Behringer , the final version is a tube crossover in the future .
Kind regards , Alexander .
 

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