Hi folks
I hope you'll forgive the rather uninspiring title to this post, but I was hoping some of you might be able to share you experiences and provide some options for where to go next... over the last couple of years my system has evolved to active multi-amplification, and right now consists of a 1" Great Plains Audio driver loaded by a 350Hz Le Cleach' horn, with the bass handled by EV SP12Bs in sealed 60L enclosures (think Klipsch Heresy). Crossover is around the 700-750Hz mark but easily adjustable being active. Amplification is vintage valves up top, new valves bottom or occasionally solid state when the mood takes me.
And so on we come to my query. Basically I'd like a slightly more open bass, so I am keen on try OB. The only caveat is that my room is small, approx. 3.5m x 3.6m, cluttered (!) and I'd struggle to have the speakers much more that 40-50cm from the rear wall. As for width of the OB we're looking at 40cm at the most.
Much as I like the thought of using of 15" per side (one either side of the horn in a sort of d'Apolito configuration), I feel 12" may be more sensible. What do you think and could you recommend worthwhile options?
I listen mostly to acoustic jazz, folk, light classical, a lot of piano...
Thanks for reading this and I look forward to your thoughts,
All best
Inamelotone
I hope you'll forgive the rather uninspiring title to this post, but I was hoping some of you might be able to share you experiences and provide some options for where to go next... over the last couple of years my system has evolved to active multi-amplification, and right now consists of a 1" Great Plains Audio driver loaded by a 350Hz Le Cleach' horn, with the bass handled by EV SP12Bs in sealed 60L enclosures (think Klipsch Heresy). Crossover is around the 700-750Hz mark but easily adjustable being active. Amplification is vintage valves up top, new valves bottom or occasionally solid state when the mood takes me.
And so on we come to my query. Basically I'd like a slightly more open bass, so I am keen on try OB. The only caveat is that my room is small, approx. 3.5m x 3.6m, cluttered (!) and I'd struggle to have the speakers much more that 40-50cm from the rear wall. As for width of the OB we're looking at 40cm at the most.
Much as I like the thought of using of 15" per side (one either side of the horn in a sort of d'Apolito configuration), I feel 12" may be more sensible. What do you think and could you recommend worthwhile options?
I listen mostly to acoustic jazz, folk, light classical, a lot of piano...
Thanks for reading this and I look forward to your thoughts,
All best
Inamelotone
Well I used to run Altec 1" drivers on Altec horns over 15" woofers on open baffle in a small room. Sounded pretty good. The big trouble with OB woofers is the loss of efficiency. Your horn could be 20dB or more hotter. It took me a long time to figure out the crossover for these.
Your 12" driver isn't going to have much bass, or at least will need a lot of power to get there. If you can use a 15", do it. The trick is to set your low pass filter very low, like 100-150Hz to fight the rising response the woofer has on Open Baffle. That's why you lose so much.
Below are the speakers in question
Your 12" driver isn't going to have much bass, or at least will need a lot of power to get there. If you can use a 15", do it. The trick is to set your low pass filter very low, like 100-150Hz to fight the rising response the woofer has on Open Baffle. That's why you lose so much.
Below are the speakers in question
Attachments
I think OB is not worth the effort in your room.
I was in a similar situation and gave up on it.
If you must do it:
Your 12" can sound nice on a 40cm baffle (midrange).
And than you can add a 15 or 18" on a U or H frame for bass.
That is 3 way of course.
I can't see a 2 way OB solution keeping the 1" CD.
I was in a similar situation and gave up on it.
If you must do it:
Your 12" can sound nice on a 40cm baffle (midrange).
And than you can add a 15 or 18" on a U or H frame for bass.
That is 3 way of course.
I can't see a 2 way OB solution keeping the 1" CD.
Here's my "very experimental" setup while I figure out a cabinet (or at least a baffle) The sound is amazingly good, truly one of the best speakers I've ever heard, and I'm in no great rush to make it "right". Don't open the picture if you're easily offended
Tops are 2470 with Radian dias and the rear open. Bottoms are 2226h, which is really much too low Q for open baffle, but saved by having a fairly large xmax. That pair of drivers should be really nice in a ported box, but I'm bewitched by the wide-open sound right now. They have trouble in the deepest bass (electronica, mostly). We're now a bit short on places to sit at the table. But otherwise this setup is wonderful.
The crossover is NanoDigi with 48dB slopes at at 1200Hz. For safety, I still need to add a sharp subsonic filter below 30. Apart from that, the main compensation is analog: a heavy L-pad on the horns, and an RC filter between the bass DAC and power amp that looks like this below (the amp has ~20k input impedance):
Tops are 2470 with Radian dias and the rear open. Bottoms are 2226h, which is really much too low Q for open baffle, but saved by having a fairly large xmax. That pair of drivers should be really nice in a ported box, but I'm bewitched by the wide-open sound right now. They have trouble in the deepest bass (electronica, mostly). We're now a bit short on places to sit at the table. But otherwise this setup is wonderful.
The crossover is NanoDigi with 48dB slopes at at 1200Hz. For safety, I still need to add a sharp subsonic filter below 30. Apart from that, the main compensation is analog: a heavy L-pad on the horns, and an RC filter between the bass DAC and power amp that looks like this below (the amp has ~20k input impedance):
Code:
dac ---[R: 1k0]-------------- amp
|
[C: 2.0uF]
|
[R: 330ohm]
|
gnd ----------------------- gndAttachments
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Read this High Efficiency Speaker Asylum . scroll to the endHi folks
I hope you'll forgive the rather uninspiring title to this post, but I was hoping some of you might be able to share you experiences and provide some options for where to go next... over the last couple of years my system has evolved to active multi-amplification, and right now consists of a 1" Great Plains Audio driver loaded by a 350Hz Le Cleach' horn, with the bass handled by EV SP12Bs in sealed 60L enclosures (think Klipsch Heresy). Crossover is around the 700-750Hz mark but easily adjustable being active. Amplification is vintage valves up top, new valves bottom or occasionally solid state when the mood takes me.
And so on we come to my query. Basically I'd like a slightly more open bass, so I am keen on try OB. The only caveat is that my room is small, approx. 3.5m x 3.6m, cluttered (!) and I'd struggle to have the speakers much more that 40-50cm from the rear wall. As for width of the OB we're looking at 40cm at the most.
Much as I like the thought of using of 15" per side (one either side of the horn in a sort of d'Apolito configuration), I feel 12" may be more sensible. What do you think and could you recommend worthwhile options?
I listen mostly to acoustic jazz, folk, light classical, a lot of piano...
Thanks for reading this and I look forward to your thoughts,
All best
Inamelotone
You could try a U baffle rather than a flat baffle . This will allow you to place the OB a little closer to the wall. You might be able to sim the response a bit with tools but before over thinking i, it might be worthwhile to just go out and buy a small 2x4 piece of plywood and build a prototype OB to see if the results are anywhere close to what you are looking for
Here's my "very experimental" setup while I figure out a cabinet (or at least a baffle) The sound is amazingly good, truly one of the best speakers I've ever heard, and I'm in no great rush to make it "right". Don't open the picture if you're easily offended
Living in London, I indeed have the same dilemma.
A naked driver sounds remarkably good for a "girl with a guitar" type of music.
But the dipole cancellation below 1000hz is enormous.
Usually multiple drivers and high excursion is needed to cope EQ.
I am building a 4 way system now (3 way plus stereo subs).
Horn ribbon tweeter from 3500hz up.
Planar dipole 800-3500hz.
Sealed 12" pro-driver 100-800hz.
Separate large BR subs with 18" pro-driver 30-100hz.
A naked driver sounds remarkably good for a "girl with a guitar" type of music.
But the dipole cancellation below 1000hz is enormous.
Usually multiple drivers and high excursion is needed to cope EQ.
I am building a 4 way system now (3 way plus stereo subs).
Horn ribbon tweeter from 3500hz up.
Planar dipole 800-3500hz.
Sealed 12" pro-driver 100-800hz.
Separate large BR subs with 18" pro-driver 30-100hz.
Agree all the way.
Without any EQ, a naked driver would be unlistenable. With a RC network to compensate the bass at +6/oct, there's still a noticeable midrange emphasis (somewhere near 1k?), but bass goes surprisingly low and very clean. But the bass driver is excursion-limited. Hitting the wall with a big pro driver does not sound good, and could be costly.
I found two things very surprising: the openness and evenness throughout the room, and the stunning level of detail and precision. I've been running multi-way systems with horns for a while, and I though they were high resolution, but this is remarkable enough to keep me up into the early hours. I want to listen to all the records again.
Without any EQ, a naked driver would be unlistenable. With a RC network to compensate the bass at +6/oct, there's still a noticeable midrange emphasis (somewhere near 1k?), but bass goes surprisingly low and very clean. But the bass driver is excursion-limited. Hitting the wall with a big pro driver does not sound good, and could be costly.
I found two things very surprising: the openness and evenness throughout the room, and the stunning level of detail and precision. I've been running multi-way systems with horns for a while, and I though they were high resolution, but this is remarkable enough to keep me up into the early hours. I want to listen to all the records again.
Dipole bass is really strange. In theory we can't localize sound source below 100-200Hz in a room. We know that dipole bass doesn't excite room modes because of net volume displacement being zero, addn perhaps because of sideways cancellations. However everyone who has heard purely dipole bass that goes really low (even up to 30Hz) must say that the sound is pure magic!
The difficulty is in implementing a practical solution - size and positioning of such an animal is very difficult in "normal family multipurpose" living rooms. With small platform systems I think best compromise are double 12" H-frame with some arrangement for force cancellation and high-excursion/low distortion drivers. Check LX521 of Linkwitz and S19 of Gainphile.
The difficulty is in implementing a practical solution - size and positioning of such an animal is very difficult in "normal family multipurpose" living rooms. With small platform systems I think best compromise are double 12" H-frame with some arrangement for force cancellation and high-excursion/low distortion drivers. Check LX521 of Linkwitz and S19 of Gainphile.
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