Anything as " fast" as SPECTRAL gear?

Okay, well thank you for showing me the error of my ways. From now on I'll try and do my best to not actually respond to your rants. Have you forgotten that I'm never wrong? Perhaps if you go back and read a past post or two you'll come finally to the realization that I've made it abundantly clear.

"Have you forgotten that I'm never wrong?"

Well, no. In order to do that, I would have to believe it before I forget it. Regardless, the statement if factually incorrect. I proved that in my last post.

02-06-15: Bifwynne
So Al, what does that mean in the context of ARC ref amps. As I mentioned above, the slew rate for my amp (150 wpc) is a paltry 13 volts/microsecond and the rise time is a sluggish 2 microseconds. The top of the line Ref 750 has a slew rate of 20 volts/microsecond and a rise time of 1.5 microseconds.

Bifwynne, doing the math for your ARC Ref 150 tube amp -
if the amp is outputting its full/rated 150W into 8 Ohms that would mean a RMS voltage of 34.6Vrms of a sinusoidal waveform & a peak of approx 49Vp of the same sine waveform. I.E. the peak-peak voltage of the sine wave would be 98Vpp. If amp traversed the 98Vpp such that the slew rate of the amp is 13V/us (as spec'd) then the maximum frequency that the amp could handle with this slew rate would be 66KHz. So, it appears that the freq BW of your amp is 20Hz (or 5Hz?) - 66KHz.
Compared to the (fictitious?) example Almarg gave where the amp was a 200W unit & had a slew rate of atleast 45V/us such that it could handle a signal as high as 200KHz.
So, the ARC Ref 150 has quite a bit lower slew rate compared the Almarg's example power amp & accordingly lower frequency bandwidth.
This also means that since the ARC Ref 150 bandwidth is just 3X (rather than 8X or 10X) the music bandwidth (of 20KHz) one can expect to hear the amp impart its own phase shift onto the higher frequencies of the music. This can manifest itself in a few ways - the highs could sound rolled-off or they could sound warmer or there could be less sparkle/shimmer compared to an amp of higher bandwidth. Nothing wrong with this sort of attribute of a power amp - many like it & many others don't. Something keep in mind.
Just some additional info, FWIW.

But are Spectral amps freaky-fast like Jimmy Johns delivery? That is what I want to know.

Really though, all interesting information here.

Is Jimmy Johns really that fast or are they just setting themselves up for failure by advertising to be?

Just wondering. have never experienced.