Instead of using MDF like my Towers, I tried the Russian Birch plywood from HD. A 4x4 sheet was $40 compared to $20 for 3/4" MDF, but since I don't have to veneer, the extra cost was worth it. The material was very nice. 13 plys in 17mm, and much easier to work with than MDF. Non-resonance like MDF too. I had some problems with splintering at first, but quickly got the hang of it.

A lot of people on this forum talked about just gluing the panels together without any kind of joinery, but I found it very difficult. Pieces slipping here and there. I actually found it easier (and faster) to use dowel rods to fit the panels together.

The build went pretty well except for a couple of problems. I forgot the make the front panels mirror images, but that's minor. The second problem came as a result of my cutting diagram assumed 3/4" panel thickness but the plywood was 17mm. Both the front and back baffle are 1/4" too wide. I have 1/8" of ledge on either side. You can see this in the photo labelled "Corner". I haven't decided to shave this off or to keep it as a design element.

The speakers were pretty much to spec, except for a couple of things. The first was I made it one inch deeper to accomodate the bracing. I'll talk about the second later.

I became a big fan of these speakers almost immediately. They are very handsome speakers. Well proportioned, with drivers filling out the front baffle nicely. They don't go down as deep as the PI Towers, but deep enough. Everything else is there. I would even say they have better midrange than the Towers. People talk about the PI Towers as an excellent deal, but take the cost and time of cabinet into account, these One PI's beat it hands down.

The second change I made was to replace the 0.5mH coil that came with the kit with a 1.0mH coil. This tamed the midrange and made for a very smooth sound. Why 1.0mH? Did it come as a result of intense calculations, modelling and testing? No. It was what I had lying around. With this mod, I found no need to do anything with the piezo. This is a very enjoyable speaker to listen to.

Most of the references to One Pi's say they make great surround speakers. I see no reason why these can't be used as main speakers either, or even in an audio/stereo set up.

BTW Wayne, not sure how things are done south of the border, but up here in Canada, the copper wire is used for the positive lead while the silver is used for ground.

Gar.

• Click on One PI

About the wire colors, I've seen some connect one way and others connect the other. Doesn't matter to me; It's just a way to keep it straight. About the 1.0mH coil, that's a good choice too. I use a 1.0mH coil when horn-loading the driver. Values between 0.5mH and 1.0mH work just fine to remove a little bit of energy above 2kHz. Naturally, larger values make it a little bit smoother, although the difference is pretty subtle. Just enough is just about right. We're looking to carve out about 3-5dB in the octave above 2kHz.

Theres my two pennies,
Thomas

Congrats on the anticipated baby girl! If you think you've got problems now, wait about 16 years. Remember what 16 yr. old boys were like?

• Tempest and Pi Construction Pix

Actually, they're not permanent stands. I made them out of scrape material I had left over. So, don't think I "designed" them for any special purposes. Although I bet that if I made some stuff up, like they're made from special exotic lumber from a remote Russian region, laminated by hand to provide resonance frequency of Mach1/PI, angles and dimensions calculated through extensive modelling by six CRAY computers in parallel, and hand assembled by a tribe of Amazon drawfs, someone would pay a couple of grand for the stands. "It improves imaging. Can't you hear it?"

The stands do help with these little guys if you keep them on the floor. But I think I might be better off rising them off the ground instead.