Hello!
I used the basic design of the Jericho horn but modified it to take Lowther PM4A drive unit [I am using the 15 ohms variety]. Took exact 7 days 10 hours per day with 3 of us working together to complete. I used 3/4" ply wood for the entire cabinets, and rounded out each bend in the folded horn. So the cabinets are a bit larger than the original Jericho plans. I used 1/4" cork sheeting to line the entire horn length thus smoothing out the contours even more. I used a felt padding behind the driver in the compression chamber. The chamber was adjusted to a vol of 5 liters and the horn throat is 60 square cm. I also put additional side panels and a double sheet of ply for the bottom and back of the cabinets. The side panels are cut in a nice curved shape [will post photos of the speakers shortly to a website] so the whole speaker has a very pleasing look. The sound is amazing, this is like achieving audio Nirvana! The portrayal of every recording is superb, all the tiny cues and details in the recording are clearly "visible". Soundstage extends beyond the speaker boundaries and is very wide and deep. Bass is just right, not lacking - very natural. I wonder why most people who write about their impressions on horn loaded full range speakers complain about less bass - I think the bass is tight, tuneful and correct. Not lacking!