I have tested this woofer i various open baffles, and find it to be very good for the price (approx 200$)
http://www.gladen.com/GladenWooferPDFs/RS15FA.pdf
http://www.gladen.com/GladenWooferPDFs/RS15FA.pdf
Hi there!
Its almost 10 years since I built my OB speakers. It all started as Visaton's "No box" project, but I used Eminence Beta 15 as a bass driver. (With Visaton B200 fullrange). Along the years I made modifications in order to improve it. First, I went active, biamping,since I wasn't happy with passive Xo's. Then, I removed side wings, since it sounded more "natural" (less resonances). Then, in 2011, after reading SLOB article, I made two more modifications:
-I just slapped two pieces of chipboard in front of the woofer, creating a kind of "slot" and..
-Modified active crossover, and made it very similar to the one in SLOB aricle. The fullrange was cut at 160 Hz hi-pass, and the woofer at 80 hz low pass + Eq circuit. The basic difference was that the hi-pass was done by using B1 buffer "blocks" while the low-pass was done using opamps, simply because I already had it, so I just slightly modded it.
The result was a satisfying speaker...until now.
What happened? I moved into a smaller apartment, (roughly 4x4 m room, sonically disastrous). Open baffles are next to a wall. It is highly impractical now to pull them out for a listen. At this position, they sound muddy and garbled. I am aware that Open Baffles are not well suited for a smallish room and they don't do their best close to the wall.
Now I am facing a dilemma: should I try modding them again, or abandon the OB concept and go back to boxes?
When I mentioned "modding" I was thinking wether I could get a better sounding "Open Baffle" by mounting the woofer like in a Mini-slob (face-down) firing into a slot (like the one desctibed in this thread)? I mean, how sensitive is the Mini-SLOB to the rear wall placement? Is it less sensitive than an "ordinary" OB?
Its almost 10 years since I built my OB speakers. It all started as Visaton's "No box" project, but I used Eminence Beta 15 as a bass driver. (With Visaton B200 fullrange). Along the years I made modifications in order to improve it. First, I went active, biamping,since I wasn't happy with passive Xo's. Then, I removed side wings, since it sounded more "natural" (less resonances). Then, in 2011, after reading SLOB article, I made two more modifications:
-I just slapped two pieces of chipboard in front of the woofer, creating a kind of "slot" and..
-Modified active crossover, and made it very similar to the one in SLOB aricle. The fullrange was cut at 160 Hz hi-pass, and the woofer at 80 hz low pass + Eq circuit. The basic difference was that the hi-pass was done by using B1 buffer "blocks" while the low-pass was done using opamps, simply because I already had it, so I just slightly modded it.
The result was a satisfying speaker...until now.
What happened? I moved into a smaller apartment, (roughly 4x4 m room, sonically disastrous). Open baffles are next to a wall. It is highly impractical now to pull them out for a listen. At this position, they sound muddy and garbled. I am aware that Open Baffles are not well suited for a smallish room and they don't do their best close to the wall.
Now I am facing a dilemma: should I try modding them again, or abandon the OB concept and go back to boxes?
When I mentioned "modding" I was thinking wether I could get a better sounding "Open Baffle" by mounting the woofer like in a Mini-slob (face-down) firing into a slot (like the one desctibed in this thread)? I mean, how sensitive is the Mini-SLOB to the rear wall placement? Is it less sensitive than an "ordinary" OB?
Yup, it seems that it is inevitable 
I am not happy to part with OB's,but a smallish square room is not OB friendly. Before making a decision (to dismantle OB's) I wanted to try a few different approaches in hope that they would work. One of them is Slot loaded OB and perhaps a Ripole. On the other hand, maybe it is a futile effort and just a waste of time and money. That's why I asked if somebody tried Mini-Slob in a smallish room, close to a wall. It seems that few people did that, and even Nelson himself didn't try that since he has a big room...
So..ZM, as you said, I'll have to look for other options, the most promising being the one with multiple (four) subs in order to make that work. I tried with two simple sealed boxes and it doesn't work, there is more bass in the kitchen that at the listening spot (room null)...
I am not happy to part with OB's,but a smallish square room is not OB friendly. Before making a decision (to dismantle OB's) I wanted to try a few different approaches in hope that they would work. One of them is Slot loaded OB and perhaps a Ripole. On the other hand, maybe it is a futile effort and just a waste of time and money. That's why I asked if somebody tried Mini-Slob in a smallish room, close to a wall. It seems that few people did that, and even Nelson himself didn't try that since he has a big room...So..ZM, as you said, I'll have to look for other options, the most promising being the one with multiple (four) subs in order to make that work. I tried with two simple sealed boxes and it doesn't work, there is more bass in the kitchen that at the listening spot (room null)...
you now my baffles from pictures - practically in corners
every regular (so baffles properly in space ) sim is showing lack of bass , considering low Qts drivers and smallish (narrow ) baffle
in situ , I can't complain about bass (both quantity and quality) , quite contrary
to remind (both myself and) you - my baffle experiment was sorta conducted upside-down - I didn't started with project on paper - I had baffles so I just screwed what I had of drivers , tried .... then analyzed
so - in your case - only further minimizing of baffle will help , if bass is , as you say , on gigantic and sloppy side
feel lucky that you have Betas , not Alphas
every regular (so baffles properly in space ) sim is showing lack of bass , considering low Qts drivers and smallish (narrow ) baffle
in situ , I can't complain about bass (both quantity and quality) , quite contrary
to remind (both myself and) you - my baffle experiment was sorta conducted upside-down - I didn't started with project on paper - I had baffles so I just screwed what I had of drivers , tried .... then analyzed
so - in your case - only further minimizing of baffle will help , if bass is , as you say , on gigantic and sloppy side
feel lucky that you have Betas , not Alphas
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Thanks Nesho,
But the arrangement is "fixed" or "dictated" by WAF. I have to find out what kind of speakers (boxes, boxless, doesn't matter) work in that room, on that position. Open baffles have the advantage of being neighbour friendly. Sealed boxes are not So, I'd rather keep whatever sort of OBs if possible, but it is not gonna be easy. I tried to run just fullranges in a box ( hi-passed). Ironically they sound better and more focused than when in OB. So, fullrangw will eather be sealed, or in a sort of a lossy box. Bass part is harder. If sealed, with only a pair of boxes, there is a null at the listening spot and a peak in the kitchen and probably neighbour's kitchen. OB bass has ironically more bass at the listening spot, but it is muddy, and clears up whan pulled away from the wall, but unfortunately I can do it only when at home alone...so, again not an option.
I haven't tried the "four subs" approach, yet, theoretically, it is what might work. As I have 8 10" bass drivers, I might be tempted to try that.
I wanted to know if using those drivers for a SLOB might be better, but...ahh...If I had enogh time to play and find myself, but it is not an option...
But the arrangement is "fixed" or "dictated" by WAF.
I have to find out what kind of speakers (boxes, boxless, doesn't matter) work in that room, on that position. Open baffles have the advantage of being neighbour friendly. Sealed boxes are not So, I'd rather keep whatever sort of OBs if possible, but it is not gonna be easy. I tried to run just fullranges in a box ( hi-passed). Ironically they sound better and more focused than when in OB. So, fullrangw will eather be sealed, or in a sort of a lossy box. Bass part is harder. If sealed, with only a pair of boxes, there is a null at the listening spot and a peak in the kitchen and probably neighbour's kitchen. OB bass has ironically more bass at the listening spot, but it is muddy, and clears up whan pulled away from the wall, but unfortunately I can do it only when at home alone...so, again not an option.I haven't tried the "four subs" approach, yet, theoretically, it is what might work. As I have 8 10" bass drivers, I might be tempted to try that.
I wanted to know if using those drivers for a SLOB might be better, but...ahh...If I had enogh time to play and find myself, but it is not an option...
the difference would be less harmonic distortion, its an old trick to "help" the woofer keep control, all the HT guys use this trick.
Lawrence