I just got a pair of M60s along with the VP-150, and I couldn't be happier with the sound. My question is this: I have an Energy e:xl-S10 subwoofer, and am wondering what would be the optimal crossover/phase settings for the sub to work in harmony with the Axioms? Are there any rules of thumb to follow?

Well, after checking the Axiom archives, I think I've found my answer:

For Axiom’s larger tower speakers--the M80ti’s, M60ti’s, and M50ti’s--depending on the particulars of room size, start by selecting the "Large" setting on your receiver for the left and right main speakers, and "Small" for the center and surround channels. With these settings, and the subwoofer set to "On," most receivers will route full-range sound, including deep bass, to the main left and right speakers, and bass below 80 Hz to the "Sub Out" jack on the rear panel of the receiver. (Some rooms may benefit from smoother bass by getting deep bass from three room locations--the sub plus the main left and right speakers--rather than a single subwoofer.) If running your left and right fronts on "Large" produces too much bass output, change the settings for the mains to "Small." You can also experiment with crossover frequencies, raising the center-channel crossover frequency to 120 Hz if you find that results in smoother dialog sound with less coloration. But 80 Hz is a generally desirable crossover frequency in most applications.

Make sure you connect a single RCA coaxial cable from the "Sub Output" jack to either the left or the right line-level RCA input on the subwoofer. You don’t need to use a Y-adaptor to connect both jacks. But you do want to set the subwoofer’s crossover to its maximum rotation so you remove it from the circuit. This is done to avoid "cascading" two crossovers, which might cause uneven and erratic deep bass output.

The only occasion where you will need to use the subwoofer’s built-in crossover control is when you are not using a line-level "Sub Out" connection from an A/V receiver. If you are running an older two-channel stereo receiver or an integrated amplifier that lacks a subwoofer output jack, connect the subwoofer by running the receiver’s left and right speaker cables to the subwoofer’s high-level or "speaker-level" input connectors. A second set of speaker cables would then run between the subwoofer and your main left and right front speakers. In this scenario, you would adjust the subwoofer crossover control to achieve a smooth blend between your main speaker’s bass output and the subwoofer’s deep bass output. Again, setting the sub’s crossover control to the 80-Hz position is a good place to start. If you use a crossover frequency much higher than 80 Hz, deep bass will start to be directional, so you risk hearing the subwoofer as a "source" of sound, which is what you want to avoid. Of course, if you have your subwoofer at the front of the room near your main speakers, it doesn’t matter if the sub’s output becomes directional. You can use a higher crossover frequency if you get a smoother transition between the mains and the sub.

How is your subwoofer connected? Do you have a surround-sound receiver? If so, then your receiver should handle the crossover setting, in which case you should turn your subwoofer's crossover dial to the maximum setting to get it out of the way. You want to avoid having both crossovers working as it will degrade the sound.

Yes, I have a Sherwood Newcastle R-945 surround receiver, and I'm connecting the sub via a line level input. Sounds like I will have to do as you say and set the crossover to maximum.

Dave, it looks like you certainly have gone through the archives. One possibility you haven't mentioned might be the simplest and best. Since your S10 has a xover input which bypasses the internal crossover and level controls on the sub, use it. Then the crossover(preferably at 80Hz)will be handled by your 945 and likewise the sub level, assuming that the 945 has an adequate range of sub level adjustment for the S10.