I have noticed that at KEF demos they use Hegel amplifiers so I would surmise this would be a nice pairing. I cannot speak to if the switch would be better or not but just the Hegel would pair nicely with the Reference 1 speakers.
Ayre v Hegel sound
My setup is comprised of a Roon-ready Ayre QX-5 Twenty DAC, Ayre DX-5 DSD disc player, Ayre KX-5 Twenty preamp and VX-5 Twenty amp driving a pair of KEF Reference 1s augmented below 80 Hz with s pair of acoustic room corrected Velodyne HGS-15s. The speakers are high-passed at 80 Hz by a Marchand filter. I've been mulling over the idea of replacing the DAC, preamp, and amp with a Hegel H390 integrated for simplicity and downsizing , but I have no idea what effect that might have on the sound. Anyone out there know or have an opinion?