This looks like the right shape. The internal diameter would be about 190 mm to sit on the outer rim of the foam. I’m guessing a thickness of 3.5 mm? I’ll need to measure how far the foam balloons upward.
1 is exactly what I’ve done, it’s 1mm thick and should go just outside the foam.
I was hoping to build in one piece for strength and convenience, although it may not be possible. That said I’m thinking of getting a new printer, so it might be possible with that, depending on how much I want to spend!
There’s no need to duplicate the shitty foam idea if we’re building anew
Kind of thinking about this
Note the foam surround goes upward meaning it will be crushed / compromised if installed face down (which it does) the uplift is greater than 1mm, not presice but 3.5mm is more likely- The circular hole in the cab is approx 175mm (Will confirm) so there is a good chance of crushing if the raiser isn’t high enough.
Ok there’s a measurement I need: the diameter of the hole in the baffle!
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I don’t think that there’s any reasonable upper limit on the thickness of the TPU gasket from a performance perspective. It might have a very slight change on the frequency response of the forward part of the driver, but hey, that’s being bounced off a plank of wood, how much worse can it get? 
The XMAX of these drivers tends to be very small, usually just 1mm or less. I think that a 5mm gasket would be sensible. Thoughts?
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Yes, as long as the BD5 mounting frame thickness (I’ll measure it) and the 5 mm gasket are factored into the pan exhaust (Lowered) to ensure proper alignment with the back-horn aperture.
Tomorrow there will be calipers, steel rulers, and me getting confused in public.
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Curious about hornstep as an assistance in working out the ideal volume for the chamber / pan / helmet / pot / hat.
What’s the exact size of the green felt gusset? Would it be reasonable to assume a steady expansion from that area to the mouth of the horn? Length of horn, and area of mouth?
With that info I think we can model in Hornresp
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Path
Some details here on the horn path lengths :
Apparently : Rear horn length: 259 cm (Really not sure about this figure 8.5 foot ???
- Overall height: 119 cm
- Height of front edge: 107 cm
- Corner to front edge: 58 cm
- Length along wall: 58 cm
- Width of front: 81 cm
- Leg height: 30 cm
- Side wall to front edge: 18 cm
- Net weight: 41 kg
21–22 kG flux
The front horn is difficult as there is no data particularly - It fires downwards onto curved jipsom (Plaster) and exits forwards - in a straight line I’d guess The TP1A front horn path length is approximately: 38 cm out to the middle front and more to the sides - I’ll measure tomorrow
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Loving this thread. “Visibly unobtrusive in a domestic setting.” Yeah but, I can smell the fucking things through my phone! 
This could be the sleeper speaker par excellence. Take eye wateringly expensive driver, and I mean like holy fuck, how much???!!! Then install it in Granny’s sewing box. Possibly literal audio abattoir, or the equivalent of sitting at the lights in your 911, and watching the Morris minor next to you dissappear off into the distance, because some nutcase bastard has somehow put a Ferrari V12 race engine in it. Love it. I so want this to work! 
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A gentleman must be understated.
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Perhaps Ritchie can provide a peacock embroidered cape to complete the look?
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Is Adam that slow?
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He’s mentally challenged but its a bit much to call him slow?
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And then you come to a corner and veer off into the trees backwards because it’s still a morris minor.
A pig with lipstick is still a pig.
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I was at madhouse hq yesterday,and was scared to even touch the box the speakers are in.
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Modelling in HornResp then.
Thiele-Small and other specs:
(Protip: ChatGPT will translate this and label everything nicely)
Guidance on entering a back-loaded horn into HornResp:
Gives me this:
I have assumed a compression chamber that’s about 20cm diameter and 10cm deep. And pi of 3.5, apparently. S1 is the other guess here, the size of the opening within the green felt. S2 is the size of the big hole between the legs.
Output:
Could be worse. But reducing the size of the compression chamber always helps; reducing Vtc to 100 gives this:
Which looks much better to me (we’re just considering up to say 200Hz, anything above that is meaningless).
So my suggestion for a first cut would be to have a very small compression chamber. Thoughts from any knowledgeable people most welcome!
But kissable!
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