What makes you build a system around an amplifier?

I most definitely agree that the statement "Some audiophiles build their systems around their amps. Some around their speakers." is true.

Further, I agree with you that "why" is interesting.

Hi Erik. Well, I'm sure you know you and I typically disagree on all things audiogon forum related, nevertheless, I'll engage in this thread. :)

I purchased a Musical Fidelity M6si in November 2015 and never looked back. I'm pleased enough with its performance - and more importantly overall value - that I chose to build around it.

Might I upgrade the amp at some point in the future, sure. But as to your question why I retain and build around it, simple; value and performance.

My system is built around my speakers which is the way it should be.

I agree. Especially if the primary consideration is monetary value. In other words, I'm of the opinion that whatever it is the system is "built around", it should clearly be the most expensive piece. Typically, that is the speakers.

Lots of interesting perspectives here, but would really love to know what it was about a particular amplifier that seduced you.

Dealer recommendation. At the time I was in a market for an amp, I didn't have the good fortune of knowing much about this site, let alone using it. The reality is there are hundreds of great brands at all different price points. I needed to start somewhere and what better place than the closets "high end" audio store? While the particular dealer I used carrier many brands, only three were on display for auditioning purposes. A McIntosh MA5200, Krell Vanguard, and Musical Fidelity M6si. I listened to them all and felt (and still feel) the MF blew the other away. Upon understanding it was half (or thereabouts) the MSRP of the others, it was a no-brainer. What specifically did/do I like about it? Succinctly, its neutral sounding muscular signature. Might there be something "better" at its price point? Perhaps, but it is likely I will never know.