Anyone using baffless speaker with a full range?


I am intrigued with some esoteric drivers, especially the PHY...paired with baffless design. What should I expect sound wise? I have a pair of Fostex Sigmas, nowhere near as interesting as these French drivers. What is the signature of a baffless design? Is there enough low end or does it need to be supplement somehow? Some of the amps that I might use these speakers with are the following:

9 Watt 300B amplifier
10 Watt SS battery/tube powered power supply
20 watt SS integrated (Opamp.)

Any experience would be appreciated!
bemopti123
You probably mean open baffle (OB), not "baffle-less"? For a comprehensive intro to OB try S Linkwitz' site as well as Melhuish's. Generally speaking OB will sound very "airy" (a bit like a stator with dynamics). To make a long story shorter, the low end starts rolling off (@~6db/octave) at a frequency determined by the width of the baffle. You'll need a woofer/subwoofer (that can be OB, too -- preferably) and proper equalisation, preferably before the amp (passive or active).

Your amps can easily drive the upper range (say from 150-200Hz and up) in a multiamp configuration. You'll need a bigger amp for the low end

Quite a few people are using wide-range drivers in OB; for a simple implementation look up the supravox site, & check out discussions over at diyaudio.

Finally, Mr Olsher's "Basszilla" speaker is a Fostex OR Lowther OB design. I strongly recommend you look it up at Blackdahlia.

OB is well worth it!
Bemopti123, I have also been intrigued by the Phy drivers, though I never considered mounting them as you are interested in. Please let us know if you do try it!
Getting bass from that type of system is a challenge. Basically, if you widen the baffle enough to get good bass, you impair the "airy" reflection from the wall behind the speaker, which is why you go open-baffle to begin with.

So, you'll have to do experiments in your room to get the "happy compromise".

I'm sure that there are some aspects of the sound that will be very satisfying in OB configuration. If you can reach an overall compromise that satisfies your listening tastes, you have succeeded.

I'd suggest making a simple baffle board, mounting the drivers, and adding temporary extensions to the baffle board in increments, to see how big you'll need it for the sound you want to achieve. Then you can make some permanent baffles. Using a slightly rearward-curved baffle can reduce edge-diffaction effects which could affect imaging. I'd expect you'll need at least a 3' square baffle surface to achieve decent bass response. Baffle-step losses will begin to occur at the frequency corresponding the 1/4 wavelength of the smallest cross-sectional dimension of your baffle. Distance from the wall behind will be important also, as in any bipolar speaker. Cancellation can occur if not properly placed.
Nelson Pass has a side web site called FirstWatt.com where he discusses his, design philosophies, DIY projects, experimental circuits, and speaker design. He wrote about an open baffle with a slot loaded base design you may find interesting. Here is the article which is a fascinating read: http://www.firstwatt.com/pdf/art_slob.pdf

Good luck on your project! 
- Steve
You might also take a look at the Alon (now Nola) line of speakers designed by Carl Marchisotto -  dipole hybrids, employing an open baffle design for mids/tweeter mounted on a large bass enclosure. I had the  Alon IVs for yeas and loved them - very open, airy un-boxy sound with good bass. Very tricky crossovers as I understand it.