These things sound great! They've only been playing for about a 1/2hr. Still have a while to break in, but on first listen they really sound good. Very dynamic and great low end. One thing though, I have them hooked to an old 25w/ch Marantz. I let them crank a little at a fairly moderate level and began to notice some distortion. Turned it down a bit and at very low volume it still was distorted. After about 1 to 2 minutes it went away. Clear as a bell. So, I got to wondering what impedance the amp was seeing from the crossover, measured it and found it to be 4 ohms. Fortunately, the amp really doesn't have a problem with this unless I crank it for a while (which I rarely do ;), but is this really very tube friendly?

Anyway, I got Diana Krall singin in my bedroom. Mustn't leave her waiting. Man these things sound good!

The eight π loudspeaker is one of the most tube-friendly speakers in the line. You're right that impedance falls to a low of just above 4 ohms at DC and very low frequencies, but it quickly rises above 8 ohms.

Tube amps are actually more sensitive to impedance peaks than dips in most cases. I'd suggest these speakers be put on 8 ohm taps, but there may be some amps that work better on a 4 ohm tap.

Transistor amps sometimes become distorted with very low load impedance, and some can even be damaged if the load drops too low. But 4 ohms is generally acceptable.

The eight π loudspeaker is over 8 ohms from 100Hz up, over 4 ohms minimum and less than 30 ohms maximum, so it is not a difficult load for most any amplifier to drive.

They aren't finished yet. At this stage they're still "naked" MDF. I hope to cover them in a walnut veneer or something, soon. I'll try to borrow a digital camera sometime and post them.

I can't tell you how good these things sound!

Jeff

Thanks for a great design.