Side mounted base drivers will not work for a dipole sub. One of the features of a dipole sub is the fact that they are directional. You end up with nulls on the sides with a figure eight radiation pattern to the front and back. If you put the drivers on a flat panel facing the sides, the listening area will be in a null and you will get no sound.
I'm sorry, but I must confess to being a little confused about what you're asking, but I'll blab anyway.
The H-frame bass module for the Orion is 11.5 x 11.5 x 24.5.
For Bob it is 13 x 13 x 29.
The width is predicated on the width of the bass drivers. The depth by trying to minimise dipole EQ. The height is due to the height of two 12 inch drivers, and a place to sit the mids on so the tweeter is at just above ear level.
You could turn either 90 degrees, but that's obviously not going to save any space unless you have drivers that can handle more EQ, such as the Stryke AV12 or 15 so you could use less depth.
And in fact I suspect it would be a very bad idea, because you would then be aiming the dipole null at the listening position, so no direct sound, and the rest at the side walls. It's kind of the opposite of what makes dipoles good.
However, you can cheat a bit to make the box narrower, as is done here:
http://www.mfk-projects.com/dipole_sub-woofer_dayton_series_ii.htm
That may have a bit more SAF.
The other consideration is that even if you could narrow the bass module width, assuming you want a one piece speaker, if you make the main panel too narrow you will have EQ problems there as well. Especially with 6 inch drivers.
There are some tests on baffle width here:
http://home.pacbell.net/donwm/system_Configuration.htm
However, the final result was apparently that too narrow was not good.
I'm not too sure what you mean by staggered bass drivers. They are behind the mids and tweeter physically, but this is an aesthetic decision and I use the delay stuff in the crossover to electrically (I hope) align them.
So, in terms of WAF, there is not an enormous amount you can do in terms of size, unless you split mids and bass like the Phoenix. Or disguise the size by funky design touches.
Like this:
http://www.gwabsynect.com/laglass/index.htm
Hope this helps.
Cheers
Steve
The H-frame bass module for the Orion is 11.5 x 11.5 x 24.5.
For Bob it is 13 x 13 x 29.
The width is predicated on the width of the bass drivers. The depth by trying to minimise dipole EQ. The height is due to the height of two 12 inch drivers, and a place to sit the mids on so the tweeter is at just above ear level.
You could turn either 90 degrees, but that's obviously not going to save any space unless you have drivers that can handle more EQ, such as the Stryke AV12 or 15 so you could use less depth.
And in fact I suspect it would be a very bad idea, because you would then be aiming the dipole null at the listening position, so no direct sound, and the rest at the side walls. It's kind of the opposite of what makes dipoles good.
However, you can cheat a bit to make the box narrower, as is done here:
http://www.mfk-projects.com/dipole_sub-woofer_dayton_series_ii.htm
That may have a bit more SAF.
The other consideration is that even if you could narrow the bass module width, assuming you want a one piece speaker, if you make the main panel too narrow you will have EQ problems there as well. Especially with 6 inch drivers.
There are some tests on baffle width here:
http://home.pacbell.net/donwm/system_Configuration.htm
However, the final result was apparently that too narrow was not good.
I'm not too sure what you mean by staggered bass drivers. They are behind the mids and tweeter physically, but this is an aesthetic decision and I use the delay stuff in the crossover to electrically (I hope) align them.
So, in terms of WAF, there is not an enormous amount you can do in terms of size, unless you split mids and bass like the Phoenix. Or disguise the size by funky design touches.
Like this:
http://www.gwabsynect.com/laglass/index.htm
Hope this helps.
Cheers
Steve
sfdoddsy said:
thanks steve. what i meant was in bob and the orion the bass drivers are in a vertical line (looking from the front) the boxes of each driver is "stagered".
what if the boxes were exactly one above the other hence the 2 baffles for the 2 bass drivers would be staggered.
the bass section of the orion looks like it is 2 (rear open) boxes. the baffle of the bass drivers is one wall of each box. the baffle is common to both drivers. now if one was to stagger the drives so that the baffle of teh 2 drivers was NOT the same piece of wood is this possible.
Here are construction photos of the Orion:
http://www.mfk-projects.com/orion_construction.htm
You are correct that the bass section is a flat baffle with both drivers mounted push-pull, with boxes built around each one.
You could easily stagger them by building two separate boxes, one for each woofer, like mini-me H-baffles. Then mount the two either with a flat piece inbetween the boxes, or mount each separately to the side panels.
Bob is a pure H-baffle like on the Linkwitz site.
The bass section on mine is actually completely removeable if I want to make the speakers two piece, or to physically time align the bass and mids.
Hope this helps
Cheers
Steve
http://www.mfk-projects.com/orion_construction.htm
You are correct that the bass section is a flat baffle with both drivers mounted push-pull, with boxes built around each one.
You could easily stagger them by building two separate boxes, one for each woofer, like mini-me H-baffles. Then mount the two either with a flat piece inbetween the boxes, or mount each separately to the side panels.
Bob is a pure H-baffle like on the Linkwitz site.
The bass section on mine is actually completely removeable if I want to make the speakers two piece, or to physically time align the bass and mids.
Hope this helps
Cheers
Steve
Not trying to hijack this thread, but just a quick question for Steve--Would you say the cost difference between the Driverack PA and a 260 is really worth it? What are any advantages of the 260 in a nutshell? I'm still planning my eventual "bob clone" system here and would like to only build it once...Thanks! Jeff
Yes, I think it is worth it. You get an extra dozen or so bands of parametric EQ available, and more flexibility in how you use them. There is also more control over phase and delays. Another nifty feature is that you can adjust output levels via an internal switch, which means you can increase inputs levels and this is a very good thing to do with a digital crossover as it increases resolution.
I got mine for $670, so I think the $270 extra cost is well worth it.
Cheers
Steve
I got mine for $670, so I think the $270 extra cost is well worth it.
Cheers
Steve
Thanks, guys--looks like I'll choose the 260--I always say, 'quality only hurts once'... Now if I can find one around that same price (cheapest I've seen new on ebay is $765 USD), Steve, I should be happy. PS What kind of mic will I need for the RTA/room setup? Any sufggestions? Thanks again, Jeff
I got mine from a place called Northern Sound and Light (www.northernsound.net) for $675, so you may want to try them first.
dbx make a measuring mic, but I use a behringer ECM8000. It works fine although it does roll off above 5K or so, which needs to be compensated for.
Steve
dbx make a measuring mic, but I use a behringer ECM8000. It works fine although it does roll off above 5K or so, which needs to be compensated for.
Steve
OK, thanks for the info, Steve. I might try using an old Sennheiser mic I have already and see if it puts me in the ballpark... I wonder if you've tried those Stryke AV15's yet? If you use one per side what kind of baffle design will you use? I assume open with deep sides like half an H-frame, correct? Keep up the good work, mate. --Jeff
sfdoddsy said:
ok i will try to explain what i mean....
right now if you are looking at the mids and tweeter the 2 woofers are firing sideways. they are mounted on teh same baffle but each driver hasa box around it the width of each box is about 6" right? teh depth and height are driver dependant right?
since each box is about 6" wide but is oppsite directions the total width is 12". however if you notice the 2 boxes are staggered becuase they are attached to a common baffle.
now what if the 2 drivers did NOT share a common baffle. what if the 2 drivers were built in 2 indepandant boxes each 6" wide x 14" deep x 14" high (for a 12" woofer).
now what if the 2 boxes were placed on top of each other with one driver firing left and the other firing right (as they now do).
the width of the system would now be 6" since the 2 boxes would be one of top of the other and not staggered as per the exisiting design.
viewing the system from the front and visualing the fron panel to be made of glass we get the following view. one driver would be 6" to the left of the other driver. while in the present alignment the surrounds of teh 2 drivers are in the same veritcal plane in the system i propose the magnets of the 2 drivers would be in the same vertical plane.
Yep, you can do separate boxes, in fact my bass drivers are in a completely separate box from the rest of the baffle.
The bit I'm confused over is the six inches part of it. The woofers are not facing sideways, they face forwards just as the mids and tweeters do. Otherwise we would be facing the side null. The width of the baffle is therefore 14 inches, and could be 14 inches high for an individual woofer.
This would make the depth of the box 6 inches.
However, the boxes, as you noted, are staggered. And then the outside panels are placed around them. This creates a total box depth (as seen by the drivers) of 12 inches.
You could mount the boxes on top of each other for a total depth of six inches, but this would reduce the size of the baffle (as seen by the drivers) so you would need more EQ.
The drivers need to face forward, or mostly so, which is why the only way I can think of to substantially narrow the cabinet is the angle them as in the link above.
Cheers
Steve
The bit I'm confused over is the six inches part of it. The woofers are not facing sideways, they face forwards just as the mids and tweeters do. Otherwise we would be facing the side null. The width of the baffle is therefore 14 inches, and could be 14 inches high for an individual woofer.
This would make the depth of the box 6 inches.
However, the boxes, as you noted, are staggered. And then the outside panels are placed around them. This creates a total box depth (as seen by the drivers) of 12 inches.
You could mount the boxes on top of each other for a total depth of six inches, but this would reduce the size of the baffle (as seen by the drivers) so you would need more EQ.
The drivers need to face forward, or mostly so, which is why the only way I can think of to substantially narrow the cabinet is the angle them as in the link above.
Cheers
Steve
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