Pass XA30.5 enough power for Wilson Sophia 2?

In many rooms and depending on typical listening levels I suspect it is enough power, but there will be times in some settings, with some music, when it might make you wish you had the XA-60s. When it comes to the Pass line, I would by the amp with the fewest watts that are sifficient, I just think the lower the wattage the better the sound, IF, it is enough to drive your speakers. The XA30s are borderline and I can understand it being a difficult decision which, unfortuantely, you can only find the answer by trying them in your home with the music and volume levels you enjpoy.

Pass may rate it at 30 wpc (its pure class A rating), but looking at Stereophiles measurements, it puts out 130 watts into 8 ohms and 195 into 4. It's transitioned to A/B but more important, it's not clipping. So on paper you might not think it's enough power but under the hood it's more than you think. Still might not be enough for "you", we don't know how much spl you like.

According to this list of specifications at the Wilson site the Sophia 2 has a sensitivity of 86db/W/m, rather than the 88 mentioned above. Based on the assumptions of 195W max amp power into its 4 ohm nominal impedance, a 4-meter (13 foot) listening distance, a 6db reduction in spl for each doubling of distance, and adding 3db to reflect the presence of 2 speakers, I calculate that maximum spl at the listening position will be 100db.

That is certainly good enough for most music at reasonable listening volumes. But ime it is roughly 5db too low to adequately handle music that has very wide dynamic range, such as a lot of classical symphonic music, if the recording is well engineered and minimally compressed.

Best regards,
-- Al

According to this list of specifications at the Wilson site the Sophia 2 has a sensitivity of 86db/W/m, rather than the 88 mentioned above.

Al...I got the 88dB sensitivity from John Atkinson's measurements of the Sophia 2 in the Stereophle review. Speaker manufacturer specs often are swayed by marketing considerations (although in this case, his measured sensitivity actually shows the speaker to be more sensitive than their stated specs), so I usually like to refer to measured performance in Stereophile, Hifi Critic, etc...Here is the link to Stereophile measurements section of the Sophia 2 review: http://www.stereophile.com/floorloudspeakers/619/index6.html.