I have a few questions (so far) regarding using Tang Band speakers. I am working on a kitbash of an Atlas mp15dc into an sw1500. I plan to install a Tang Band speaker under the radiator core a la Bob’s scheme for his Atlas switcher.
My first question is pretty reasonable, I think. The Tang Band speaker modules have two “speakers” in each, one a round cone and the other an oval shape. Which one is the primary speaker and which one is the passive radiator? Does it matter which one is positioned where in regard to the opening that the sound will come out of?
Do both speaker and radiator exhibit excursion, and to the same degree? I know Bob has indicated that fairly significant excursion happens for the larger Tang Band modules.
Now to the silliness. I know almost nothing about the science or rules behind speaker design, so this may be the dumbest question ever regarding speakers. I have both 1931S and 1925S modules on hand. I would prefer to achieve the extra range of bass response possible with the 1931S, but I must concede that it will not practically fit inside the shell, constrained by the width. There is plenty of room lengthwise for both the 1931S module plus a Loksound decoder. If all else fails, I will use the 1925S as a straightforward solution.
However, I’m curious whether the bass response is a product of the passive radiator, or is it a product of the overall design of the module, including enclosure. Would it be feasible to cut the face of the module out of the existing enclosure, with the primary cone and passive radiator still intact, and then build a new narrower enclosure around those parts. I have no idea if there is anything other than air inside the current enclosure, something like baffles maybe? I have no idea if the volume of air inside the enclosure is critical to the sound produced, or if dimensions are critical with respect to sound wavelengths or similar. I could see where these things might matter, but I don’t have the knowledge to know if they really do.
A 1.25" wide enclosure would definitely fit inside the shell, and possibly something as wide as 1.375" would fit. I want to get the best sound possible if I’m going to bother with it at all, and I think the bass response is critical for that. I don’t have to get the 1931S into this switcher, but I’d sure prefer to do so. If what I’ve proposed above is foolish, I can always use the 1931S in another project where I have more room.
Any ideas, tips, or admonishments are welcome and appreciated.