Frugel-Horn XL for Alpair 10.3/10p, Fostex FF165wk, more

frugal-phile™
Joined 2001
Paid Member
I have never looked closely at that, just enuff to know it is rehash of the work Olson did, work that impacted the midPod development.

But the formulas (empirical) might provr useful.

The basic first formula is BS(-3) = 4560/baffle width in inches. The ideal target for supraBaffle width would be close to = BS(-3)/0.707. With the goal LF target somewhere between about 300-350 Hz. That might prove large.

dave
 
frugal-phile™
Joined 2001
Paid Member
Bigger than i would do. The blue is as small as i’d go, it gives just enuff coverage to put some pod bits on the side & top (i’m looking at the ellipse). Anywhere between the 2, get to close to yours you are pushing your luck.

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The dotted line represents what i would consider a minimum size. The deflector pushes the horn moiuth out from the wall. You don’t want to push it out more than wher eit is comfortable bass wize without.

If you are considering a woofer, width is often determined by how much volume you need. It is tall enuff to be a short, wend loaded ML-TL.

dave
 

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Thanks Dave,

could it be that the front baffle, instead of being rectangular, has the shape as in the left (diameter chosen to let the rear parts be mounted without modifications), and then behind that baffle the width goes as wide as the 390mm deflector (as in the right)? Or being "supra" Baffle, it must be mounted on top of the front baffle?

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I forgot one point: would you use the deflector as end loaded ML-TL woofer?
By now I'd just use it as deflector, because I would like to avoid crossovers on these speakers, but keep the possibility to add it in the future.

I would like to ideally install the speakers around 8-10 inches (20-25 cm) from the rear wall, on the sides of the fireplace, around 10 feet (3 meters) from each other, pointing just in front of the sofa.
 
frugal-phile™
Joined 2001
Paid Member
Exploration of supraBaffle is still in its infancy. Play.

The goal to smooth the 2π to 4π transition, and push where it happens down.

Where it needs to take effect will depend somewhat on room & placement, the B&W pod (and the Eclipse) suggest the best shapes to smooth things out. The trailing edge is as important as the front.

dave

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I can try to ask to a friend of mine to model something similar on his 3D printer, but honestly I would not even know hot to determine the internal volume and reflex pipe.

What I can try to do is to see if I can inscribe the FHXL into the egg shaped B&W pod and Eclipse. ...but I would say first of all start building the FHXL as they are, with that 390 mm wide deflector.
 
Finally got mine finished! I honestly forgot how good these sound... I really don't like sapele but it was what I had lying around, and good practice for veneering. I have a lot of woodworking experience and I've found veneer to be challenging but I think I have the hang of it. Next time I will plan to splurge for adhesive backed. I used the contact cement method for another pair and it rippled (could be due to saturating it with waterlox, probably should have wiped that on), this time I used titebond and iron and it went okay but a few small bubbles. I used a black gel stain on the sides, and put magnets under the veneer so they can be used without the grills.
 

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Another set just finished! Must say that I’m impressed. I built a pair of Decware DNAs several years ago and loved the sound of the 10P in them. The FHXL has more bass, I’m running mine uncompensated, where I have to add about 3db bass boost to the DNAs. The big difference I see is the bass of the FHXL is more dynamic. Faster if you will. More impact. I’m still trying to decide but I think the DNAs will reach lower, into subsonics. I don’t have much listening time yet with the Frugels but the bass in a song or two seemed to be “confused”. I believe it to be a reflection issue and will play with positioning before I badmouth the speaker. I’m running 40 grams of well teased poly upstream and currently nothing downstream. I used veneer that I had left over, curly maple and walnut, the walnut was too short to just run vertical so I cut strips and put them together at an angle. Frugal. Or cheap, but I like the outcome. I did burn through the veneer to the paper backing in one spot, anybody know of a way to fix it? Because of the current price of Baltic Birch, I used 9 ply Samauma instead. No voids and $44 a sheet. Also, if you don’t mind the grain of the internal divider running cross instead of up/down, you can get everything but the top out of a single sheet. As an aside, I found the plans for these “in the wild” but still donated my $10 if anybody cares. Just a heads up that they are loose.
 

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