Just realize that there have been actual double-blinded studies proving that there is no statistical differences among amps.
The one about the $300 Pioneer AVR vs the $10,000 Boulder amp comes to mind.
Amps, pre-amps, DAC, cables don't have sounds of there own.
DSP/EQ in processors will sound differently.
In direct modes, you will not notice a difference between a Yamaha, Denon, Marantz, Pioneer, Onkyo, Harman Kardon.
People will claim to hear all kinds of things. But double-blinded studies have proven otherwise.
Level-match all the amps, and they will sound the same. The problem is, most people do not level-match the comparisons.
So just don't tell people to break-in the speakers, and don't tell them to buy new AVR or amps.