Xcortes,
I'm so sorry I did not see your post until now. By some bizarre glitch in my browser cache it held an old page and I was wondering today if there had been any posts recently. Went out and then back into the forum and here was your post!
So indeed, the Feastrex drivers really are the cat's meow. The permendur field coils especially, Teramoto-san and Akiyama-san describe them jokingly, but effectively as "drugs without the delivery."
I'll mention up front, however, that I'm also not sure if they've ever truly shown well at audio shows in the US as nicely as I heard them in Japan. They can't be hurried. Often times, the drivers at the shows had only a few hours on them. (except for the Lotus group's "Granada" which received rave reviews).
My Oniyanma design is awesome, but I never got the chance to take it around the circuit of audio shows. One time I got the chance, family matters intervened. By now, I am ready to push the design (and envelope) further and am actually selling the original Oniyanma enclosures to help finance the next generation of RnD work to be done.
Over the course of my involvement with the drivers, I have heard Feastrexes in hundreds of settings and I've also heard (and built parts for) every model in their production line while I was an apprentice of theirs, including my own pair of drivers built from start to finish at the end of the apprenticeship. It was a true honor to work with those guys.
There are some idiosyncracies to the way one designs for these drivers, however. In some manners, they sound better in a cardboard box than a back loaded horn, (in my opinion). They have so much energy that to try to contain it is foolish. They'll make you hear deeper into the inner purities or impurities of the cabinet materials, to a degree no other driver has for me. (I've even owned a pair of the FE208ES-R). Feastrex, by comparison, makes deep excitation of the cabinet. It also "leaps" its sound into the room like none other. And so this is why it is a bad idea to tune them very low (and into the higher energy domain of cabinet wall excitation). Mr. Teramoto used to say that "If I was so interested in getting bass out of them, then concrete is a good option. Silly Americans..." But I (and Feastrex) like the tonality of wood, and especially the way that the Feastrex drivers positively interact with it when everything is truly done well.
I've never used the Oniyanmas with subs, but the next generation I will most likely explore some subwoofer options. Getting their best requires a similar approach to the way I tune my Orcas (to not stress out the full range driver by tuning it too low). Basically, in light of them not being advisable to be tuned super low, then indeed, some subs (20-60hz) would be awesome. Rythmik servos would be good, as would some nice field coil or alnico 15" woofers. GPA, Kilimanjaro, Goto, options as well.
Also, it is important especially to cut, clamp and assemble the cabinet with utmost respect to acheive a destressed cabinet environment. To do so requires prolonged processes on the tooling, run carefully, slowly, and "dead nuts on" (which among cabinet makers is a technical term
But yeah, definitely respectful to the requirements of every step to achieve good sound. To do any less is to blatantly disrespect the effort put into the drivers themselves.
In regards to the next generation of Feastrex cabinets being released, I'll mention that I do have something pretty exciting planned, but it will be into the new year before it is formally released...
Best,
Clark
