Which tap

So my speakers are rated at 4-8 ohm (Canton Reference 9.2 dc), my amp is an ARC Classic 60. The amp has 4, 8, and 16 ohm taps. 
I’m not sure if I can tell a difference between 4 and 8 yet. That being said which tap it it better to err on?
You want to attempt “ light loading “ using the lowest tap that avoids clipping- that will typically sound best - but actual listening is required.

the late great Roger Modjeski or Music Reference fame ( RIP ) was a big proponent of light loading - but his amps also had IMO genius level hand built transformers.


enjoy the music