On “I Put a Spell on You,” Springs’s piano and her alto voice both sounded fuller and richer through the KEFs. Her throaty inflections were more clearly an artistic effect, rather than sounding like an aural artifact, and her sibilants were less hot. Sanborn’s sax had just as much bite, but less of an edge. The soundstage was not as deep or tall through the KEFs as it was through the Airpulses. And again, the musicians were better differentiated with the Airpulse speakers. Might as well be a gold mine in there with that many input selections. Sheesh. What kind of connection do you prefer? Well, the A300 probably has that covered. Included in the design are all of the following:

Ribbons may sound superior, but they aren't perfect. Since they are extremely light and don't have a normal voice coil, their internal resistance is very low. This makes driving them difficult without a specially designed amplifier. Being so small, they can't move a lot of air either which means they are only effective at high frequencies. To compensate, a wider range woofer is required. All that being said, ribbon tweeters are a considerable upgrade. However, their high cost means they are only found on very expensive systems.In this case, the A300 is more dense feeling and more solid in nature than my older HDP6from AudioEngine. Beyond that, the speakers are incredibly sexy. Take note of my setup, which I have tested in a more spacious part of this same room with much more depth between each side wall, only to find no difference in actual presentation qualities. The power supply and amplifiers in the left and right speaker of the A300Pro is completely symmetrical. Each speaker has an internal 150W high-efficiency, low-ripple switching power supply. The SM200 speaker features a long-throw over-hung voice coil, crafted from pure oxygen-free long-crystal copper wire.

Starting with some objective analysis thanks to our friends over at miniDSP. One important characteristic of a speaker or headphone system is how accurately it reproduces sounds. This is called the frequency response and ideally, it should be very flat. That means the sound coming out of the speaker exactly matches the signal going into it. To test this, you play a known audio signal through the speaker and measure the amplitude of the signal coming out. To do it accurately, you need a specialized measurement microphone that has been calibrated to ensure it has a perfectly flat frequency response itself. I used the Room EQ Wizard (REW) to produce the frequency sweep and perform the analysis and the UMIK-1 from miniDSP as my measurement microphone. From the front, the two speakers look identical, except for a small window at the bottom of the primary speaker that houses an IR receiver for the supplied remote control, and a monochrome OLED that displays source information, as well as numerical indicators for the volume, bass, and treble settings whenever these are adjusted with the remote. The remote only functions when the speakers are in wireless mode.

Bluetooth receiver of P100X is Qualcomm's latest V5.0 chipset QCC3031, which can support aptX HD codec, offering a lower distortion, higher resolution Bluetooth audio effect than traditional SBC codec.