I have been asked by a fellow ANer to post the latest news from the Feastrex NC research lab.
I have been digging them, of course. They have mellowed out and are very exciting and musical to listen to. A few more people around the world have bought the drivers and built this same cabinet per plans that I posted on diyaudio, designed by scottmoose and Martin King. It allows the speaker to speak clearly while giving a decent bass extension, considering it is a 4" driver.
I built mine in solid pine, which turned out to be very lovely sounding when it wasn't resonating with the music. But when it did resonate (most of the time), the coloration was severe. Still listenable because it is pine wood box and paper cone with all tubes, so what's not to like... But to a perfectionist like me, eventually it started to get on my nerves everytime the cellist played my jaw would rattle. So I gave away those boxes to a friend in CO, Mike who worked the Feastrex room as translator for Mr Teramoto when he visited for the RMAF show.
I'm waiting for a new design to emerge from planet-10 audio, designed by scottmoose and Dave Dlugos, which will be more highly optimized for the driver than the original "Freddie Chang" that I built. It is larger coupling chamber, and two horns instead of one, looks like the Harvey pictured above. But until that is born, I am gonna rebuld the smaller Freddie cabinets again, this time using a different approach, and hopefully kill off most of the cabinet resonance. Read TAS interview with Magico's Alon Wolf this issue to get an idea what I'm thinking about.
I have also used Martin King's mathCAD sheet to design an open baffle for these drivers. I have them playing now, and they sound incredible. All crap from the box is gone. But alas, no bass. But there is a lot of that box sound that I like, and miss, or at least for the first 10 minutes. OB is very natural and uncolored, but we like our distortions and get very used to them. Strip it all off and it seems less exciting, more plain. But the ease of listening is so much better. It just wafts through you with no pressure at all. The simulator says it rolls off about 12-18dB starting at 200Hz, but dead flat above that. I bought a pair of Peerless XXLS 12" drivers to mount in the baffles and hope to do that this week. They are ultra low distortion bass drivers with gigantic excursion. I think they will be fast enough to keep up with the 2g moving mass of the Feastrex, I hope so. Modelled in mathCAD with the woofers and no boost, the OB speakers are flat down to 100Hz with no woofer frame and no boost, woofer only moving 3mm out of its possible 13! and rolling gently down to -12dB at 30Hz.The Peerless will need a lot of power, but I can crank in some boost to flatten them out as necessary using...
I also got a Behringer DCX2496 xover. I ordered the upgrade kit from Pilgham Audio. It will be a while before that is running, but mgalusha says it is a great mod. They are bringing out more kits for DCX coming soon.
So far I can only say about the Feastrex drivers that they sound effortless, smooth, rich, ultra detailed without any edge or annoying factor. The bad thing is that I can hear everything that is wrong with my electronics. Hum, tube tinks, hiss, whatever, it is an electron microscope. It is hauntingly real with music that compliments its one limitation of little bass. In the BVR cabinet, bass is flat down to 70Hz, so you can easily enjoy any music, and even feel it in the chest now and then. The treble response is just like a separate tweeter, but richer, more natural, cymbals sound real, instead of metallic. Extension on things like chimes, bells, tinkly things is much stronger sensatioin than my ribbons on my Legacys, which I recently learned are just cheap $20 planars, well implemented... Voices like Alison Kraus or Tallis Scholars just melt me. String quartets are awesome. Symphony is also good, and plenty enjoyable, but I miss the vibration of low notes on bass violins. My wife's Chris Daughtry is not as exciting as on the big speakers - duh. So I keep experimenting. I'm hoping the new design from planet 10, to be called Maiko, will give the extra bit of bass that is needed to make a truly high end speaker. If not, the 2 way OB will work good.
The drivers have a lot of inner detail especially in the midrange. This makes them very magical, and special sounding from the very first note. It is a funny tradition starting now to to observe people the first time they are deflowered hearing Feastrex for the first time. Audible moans and groans, explitives of disbelief, wanting to talk about it and listen at the same time, and excitement, like a crack head wanting to score a fix. haha It is an easy sell, except for the price. But compared to many $4000 speakers (like mine) this kicks ass for pure enjoyment. You also have to factor in improving the electronics. No point in having all that resolution with a suitable signal to play, or too noisy.
I also plan to do another anechoic experiment with them, which is the reason I bought them actually. That is starting to come together now. Shitty weather slows down wood cutting.
As for where to get them, Joe Cohen of Lotus Group is the importer. They list for $4000 pair for D5nf the drivers only. Other models available, but these are the cheapest - oops, sorry Bill, I mean least expensive...
Delivery is about a month, fresh from Japan. Contact Joe by email on his website, or call him. Any Lotus Group dealer should also be able to order them for you. I got mine from Dennis Jeffers in Charlotte, NC, helluva nice guy.
There are a lot of posts about the drivers and these cabinets on the web now. Google will get you there, or check out diyaudio, asylum (search chris witmer, or just feastrex), and now some action on AC with floobydust just finishing his pair, and loving it. puremusicgroup.com has forum with Feastrex section.
I think the excitement abot them is building up steadily. They just had a good show at CES, with mention on stereophile blog and 6 moons but there is a long way to go yet.
I will play mine again at the next meet we have here in NC, hopefully they will sound a lot better than last time when I screwed them up badly with incorrect bracing and absorbtion inside. Live and learn. I will never forget the look on Shane's face like he fell on an icepick.
These NC audiophiles are tough please.
It is expensive, but on first listen, you will understand why. Hopefully by next year's trade shows, the cabinets will be sorted out to allow their incredible sound to be obvious to more show goers. Feastrex's own bass reflex and passive radiator deisgns were not optimized at RMAF, so the $50 diy Freddie sounds much better IMO, maybe a little less bss, but much more a whole cloth.
Sorry if I repeated myself or rambled. Hard to avoid with me..
Rich