Ayre V-Kxe and Thiel 2.4s

I've never understood the argument of using the efficiency rating of a loudspeaker insofar as determining power requirements for an amplifier. I'm beginning to wonder if there is more to the equation. I'm currently using the V-5xe with Hales T8's which run at 87db and have nominal impedance of 4 ohms. I've been told by experts (someone who actually sold them) that the speaker needs enormous amounts of power. With the V-5xe I have never turned the preamp volume setting past 9 o'clock. With a threshold amp (which had the same power rating), anything past 8' o'clock would shatter window panes and my ear drums.

Unsound,
The obvious point is steve`s CJ amp drove ithe Thiel and the OP`s Pass amp apparently struggles. Among other choices perhaps he may want to at least considerThe CJ amp or something very similar based on steve`s great sonic result.
Regards,

It's a funny world out there... wish we could all just take disks/equipment over to each other's house to examine the true state of affairs. Even since I made this thread, my INT-30A has kept improving (I'm about a month into ownership but leave it on constantly), and it is simply jaw-dropping spectacular a lot of the time. I'm growing increasingly concerned that the only thing I'll like better on the next amp will be the bass control and I'll only notice that when I listen to the very specific types of music that the deficiencies noticeable.

Unsound, sorry, but can you elaborate on how knowing that the Pass is a 15 amp draw will help me?

Russellrcncom, the placement of the volume knob might not be meaningful with re: to the respective differences between power output of the different amplifiers. The amplifiers just might have different input sensitivities for full power output, and your preamps might be providing that much or more or less than that much output at a given setting to drive your amplifier to full or near full output at less than the preamps full output. For example: one amp might need 2 volts to achieve full power output, the other amp might need 2.2 volts to achieve full power output to achieve full power output, while your pre amplifier might be able to put out up to 7 volts at it's maximum setting, and up to 2 volts at it's 8 o'clock setting.