Size of Horn for 3" Driver

[konut]

Not a DIY guy, just curious as an intellectual exercise. Having owned all types of speakers, from full range to planars to 2 way, 3 way etc, in various implementations, ie ported, sealed, aperiodic, horns, etc, it has occurred to me that the following scenario might be a very good way to optimize what is currently available.
If one were to take one of the better 3" drivers currently offered, what would the size need to be, depth, length and diameter at edge, to obtain linear response down to 200hz, utilizing an oblate spheroid flare?

[moray james]

Take a look here for some good ideas, you will need to be concerned about the driver peramateres if you want to run it in a horn. Hope this is of interest. Best regards Moray James.
inlowsound.com

[konut]

Thanks for that. It looks to be more of an exponential geometry for that paper horn. I would imagine a 3" or 4" Alpair driver would shorten the horn and using an oblate spheroid flare would shorten the horn further still. Maintaining the the 30" mouth would still be required to reach the 300 hz low end probably. Trying to go lower would require a larger diameter.

[moray james]

The construction method given can be used for any shape mold you like. John has done some fine work. Have you given any thought to the Unity or Synergy approach. It is a less complex build and has much to admire? There are a number of ongoing builds at the moment so a lot of ground work has already been done. Higher efficiency and lower distortion in a very domestic size. Best regards Moray James.