218 kick horn

The measurement some time ago was before the foam/fiberglass resin throat mod. I hope I can recreate the exact same environment and take another measurement that would be worthy of a somewhat accurate A/B comparison.
The servodrive horn length is ALOT longer than these things. Would be something else if it went anywhere as low as them. :whistle:

It might be impossible to recreate the exact conditions you had last time as there where quite a few obstacles as far as I remember.

It is not only the horn length that determines how low it goes. It could be interesting to see a measurement of the servos and this horn under the same conditions.

I am going to throw a couple of these together (as soon as my new saw gets here) Dref I am going to try the letterbox this time
What do you think?

186 might be easier chamber to match volume wise. Same horn other than chamber. On the 1850s (I built 4 of them) the magnet is pretty close, although slightly diagonal to the bottom chamber panel. Volume wise, I think the chamber on the top driver would end being too big. You can do the pipe trick you did with the kicks at the start of this thread, and it should not be too much of a problem that they are different sizes, but the two chambers together will be larger than two of the chambers on the original design and it might end up closer to a dual 186 anyhow. Cheaper drivers for those though.

Oh, I was just thinking about it, and you could actually make the top chamber smaller quite easily with a straight flat panel at the top about where it says 190 if you really wanted it to behave like a 1850. It would be a strong brace too, considering it would almost exactly opposite the first two braces in the horn path. Little bit of dead space, but not too much.

I was going more towards the 186. A looser horn path and bigger chamber.

Green being the letterbox, black being a pipe or slot of some sort to equalize the rear chamber size. It would be easy after the fact to make the chamber size smaller if needed.

Any reason why you are going for an S-fold this time?

Are you planning on using the exact same horn as the 186/1850 horn?
If you tell me what driver you will be using and an estimate of the rear chamber volume, then I can make you a quick sim if you like?

I am going to bend all the horn path ply. Easier to do with the S-fold style. I am up for a challenge The folding won't be exactly the same as the the 186, but similar- smoother expansion.
Thanks Dref, but I have no idea what drivers I will be using yet.....

I am looking forward to see what you come up with. Shouldn't you give them their own thread btw?

Have you considered a layout like Mykey's C4-S? It doesn't come much smoother than that without significant amounts of wasted space. (Only single driver though)

I am not familiar with the C4-S. Do tell......