Recommend driver for 1.16 ft^3 box

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frugal-phile™
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So then which Mark Audio driver? Any 6.5 inch?

If you want to stick with paper the 5.25” A10p. It goes lower, higher and edges the larger driver in midrange, and is almost as efficient. More versatile as to box size (the A12p seems to really want a big box) and cheaper to boot. The 6.5” A12p edges it out only in how much air the larger cone can move.

dave
 
Regarding the "Castle" microtower that Dave mention a few posts back, I've built at least 3 versions - the first as seen in his posted photo with CSS EL70 (now residing in my mom's living room), and two with top panel angled forward at 10dg. I also built a single pair of the "true" bipole, but much prefer the placement flexibility and spaciousness of the Castles.
With appropriate dimensions and vent tuning, this topology should work with a wide range of drivers, either full-range or simple 2-way combos. I've thought about an upscaled version with either A7.3, or A10P and A5.2 as tweeter.
 
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I'm back on finishing up this speaker. Boxes built except the front baffle.
Since it's a full-range driver with a whizzer cone, should the driver be flush mounted?
If there is zero difference, I will just surface mount.

The basket is 5.5mm thick, so it's not a trivial rise above the baffle.
The front baffle edges are rounded.
 
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Thanks. I'm struggling to remember what "BR" stands for.

Using the W6-2144 which is 6.5".

I'm going a different route with the box type.
Could be a total failure, but I have to see. :D

You have any idea if the driver has to be flush mounted or can it rest on top of the baffle?

thanks.

V.
 
If you want to stick with paper the 5.25” A10p. It goes lower, higher and edges the larger driver in midrange, and is almost as efficient. More versatile as to box size (the A12p seems to really want a big box) and cheaper to boot. The 6.5” A12p edges it out only in how much air the larger cone can move.

dave

My first experiments look promising with A10p. Published parameters seem to be spot-on.
I have made a first experiment in sealed box of 28l (effective) and I like so much that I think I will stick to this. The volume is perfect. This gives a total Q of about 0.71 once the Zout of ITS amp of 3.75R is taken into account. F3 around 60Hz and then the usual 12 dB roll-off of sealed box, actually a bit less than 12 in practice. F10, should be around 35Hz. About 87 dB/1W average efficiency and very balanced presentation. Nothing in the way between amp and driver thanks to the "built in" BS compensation. Pretty impressive for such a small driver!
Given the radiant surface and the linear excursion I think it would useless to ask lower for F3. In that case a transmission line might be the choice but I wanted a book-shelf loudspeaker. Now I need to work on the shape to eliminate diffraction and other un-wanted stuff that spoil resolution and cause troubles....:)
 
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Here's what I came up with on gut instinct. Didn't use any software to design. It's slapped together. Right now it's breaking-in. Has 16 hours so far with break-in track and music.

On first start up, it was harsh, no bass, shouty and irritating. It did have great dynamics, but that could have been due to the peaks in the upper mids and over all shouty character. Has good 3d presentation. There's no lack of extension. Bit of a directivity issue, but not terrible.

After 16 hours- more bass was present, especially in bass heavy tracks. Tight, but not chest pounding. Was less shouty, still emphasis in upper mids. Does benefit from front wall re-enforcement. Likes space on outside of speakers, away from boundaries.

It's just a FR in an aperiodic box 1.16Ft^3 filled with 50% loose poly and corrugated stuffing behind the driver. Path from rear of driver to the aperiodic port is clear. Box is completely glued together, my first time using only glue. Used Tite Bond II. Internal wiring is QED ~16 ga, maybe even 18 ga, not sure. Wire has a foam jacket. Used heavy duty binding posts, which I don't like, but it's what I had on hand.
No filters yet.

I think the 89+ db sensitivity is pretty much spot on. I recently picked up a pair of Sonus Faber Grand Piano towers at 90db and they have the same amount of output in the same space.
 

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