From my own experience lower Q drivers with EQ tend to sound better on open baffle then higer Q drivers. Max output is defined by Sd and Xmax.
When trying to achieve more output adding Sd, as in more drivers, almost always sounds better than adding Xmax. Big woofers with big magnets with lowish moving mass and lots of them, that's the secret sauce in my experience
When trying to achieve more output adding Sd, as in more drivers, almost always sounds better than adding Xmax. Big woofers with big magnets with lowish moving mass and lots of them, that's the secret sauce in my experience
I agree with Sjef. In pure theory there would be no difference... but in actual practice, high Xmax drivers have lower efficiency, more inductance, more mass, and more distortion than a low Xmax driver with a larger Sd. Much better to achieve high output with Sd than with Xmax. It's also less costly.
Real life experiences
I have had very good results with Open Baffles using large light cones no matter the electrical parameters or Xmax of drivers. Very low audible distortion and enough sound pressure to make the listening uncomfortable. Measured sound response very linear to 30 Hz or even lower.
I have had very good results with Open Baffles using large light cones no matter the electrical parameters or Xmax of drivers. Very low audible distortion and enough sound pressure to make the listening uncomfortable. Measured sound response very linear to 30 Hz or even lower.
Troels agrees.
OBL11
"First of all: From a visitor hearing the prototype OBL-11s, I can report that these 15" Eminence DeltaLites beat the crap out of Eminence Alpha 15A, which is often referred to in OB connections as being an ideal driver for this application. This was my expectation and what I had hoped for by choosing a fairly low-Qt driver and applying the equalisation step."
OBL11
"First of all: From a visitor hearing the prototype OBL-11s, I can report that these 15" Eminence DeltaLites beat the crap out of Eminence Alpha 15A, which is often referred to in OB connections as being an ideal driver for this application. This was my expectation and what I had hoped for by choosing a fairly low-Qt driver and applying the equalisation step."
Questions about the Open Baffle concept
I am curious as to why the OB discussions often concerns bass and the extension hereof. To my experience it is quite easy to get reasonable bass performance from OB systems. By resonable i mean linear output from 30 Hz or so and dry precise bass with a sensation of live music. I have had OB's with dual 10", 12" and 15". In dipole or ripole configs and all of them have had basically the same bass in different rooms. I have always used MiniDSP with or without room correction and have tried to make as little use of correction as possible.
BTW. I find it much more interesting to dicsuss how it is possible in OB's to avoid what i call midrange smear. To me it seems that when bass is managed correctly the midrange opens up and becomes much more articulate and precise. To me this is the real benefit of OB's along with the airyness of the treble and the soundstaging as deep and wide - which i percieve as the speakers completely disappearing.
I am curious as to why the OB discussions often concerns bass and the extension hereof. To my experience it is quite easy to get reasonable bass performance from OB systems. By resonable i mean linear output from 30 Hz or so and dry precise bass with a sensation of live music. I have had OB's with dual 10", 12" and 15". In dipole or ripole configs and all of them have had basically the same bass in different rooms. I have always used MiniDSP with or without room correction and have tried to make as little use of correction as possible.
BTW. I find it much more interesting to dicsuss how it is possible in OB's to avoid what i call midrange smear. To me it seems that when bass is managed correctly the midrange opens up and becomes much more articulate and precise. To me this is the real benefit of OB's along with the airyness of the treble and the soundstaging as deep and wide - which i percieve as the speakers completely disappearing.
Interestingly these Deltalites 2515 praised by Troels for bass on a wide baffle is also praised by bushmeister for 150-600Hz baffleless, as well as CharlieLaub also baffleless. Must be a special driver.
Has anybody used Troels' JA8008 in OB? I wonder how much better than my B&C 8PE21 they are.
You mean Troels moved to Ciare/Faital? Interesting.
FWIW, I have Faital 18HP1010 bafleless 70-275Hz and like them. I haven't tried other 15-18" though.
I can safely say that I do not know.
However, Briggs recommended side wall placement, a few others have found good results there too, that "could" in effect increase the baffle with infinitely on one side.
The plot thickens.
JE Labs Arkiv (up to 2008): G. A. Briggs - Evolution of the Wharfedale SFB3 Open Baffle
However, Briggs recommended side wall placement, a few others have found good results there too, that "could" in effect increase the baffle with infinitely on one side.
The plot thickens.
JE Labs Arkiv (up to 2008): G. A. Briggs - Evolution of the Wharfedale SFB3 Open Baffle
All,
I posted photos & geek gallery of my speaker design projects https://perrymarshall.com/speakers/
Several interesting OB designs here including DSP files.
Perry
I posted photos & geek gallery of my speaker design projects https://perrymarshall.com/speakers/
Several interesting OB designs here including DSP files.
Perry