How much does rear horn loading add to full range driver?

If you can find it, audition Charney Audio speakers.  They employ a fairly large quarterwave rear loaded horn on 8” drivers.  The bass is remarkably good. Voxativ does the same.  Doing it right involves some fairly complex woodworking for the cabinets which means it is not a cheap approach even if there are savings from having just one driver and no crossover.

I've listened to numerous BLH Fostex cabinet designs using drivers in the 3"-8" range and  could hear usable info down to around 50Hz, depending on how close they were positioned to the front wall/corners.

This said, the sound down there was somewhat disjointed from the rest.

A few exceptions to this were (#1) speakers from The Horneshoppe.

Not certain what to call the open backed cabinet design, but the sound was nicely balanced (they used a 3"-4" driver and I only heard them once placed in corners).

The other (#2) was a wide/flat TL (open @ the bottom) that used little Ted Jordan drivers.

The cabinets I heard them in were DIY (made from some plans on the WWW).

Here's a YT video of a similar/like speaker and I think that it uses the same driver (looks the same).

DeKay

PS:

What are the speakers you are considering?

DeKay