I doubt the amp would be ideal for 4 ohm speakers and if your Focal's are spending much time around there then you would not only have a sound pressure level weakness, but also a frequency response problem...possibly.

The amp does get great reviews and if you don't have a big room or listen very loud at all, it might be a nice combo within a rather narrow range of loudness...like pleasant, quiet listening from the nearfield.

If you know yourself and your requirements for sound pressure, there's no reason it can't work.

At 91db on your speakers and 6 watts on the amp, you could convert that to something rather common in a solid state and typical standmount speaker combination, 85db speakers and a 24 watt amp. There's nothing wrong with it other than absolute sound pressure capabilities...assuming the speakers really are 8 ohm designs as indicated by the manufacturer.

It's not like the combination wouldn't play reasonably loud, it would. In fact, many people are shocked at how little power they are actually using when listening at normal/sane levels.

I would say that you need an amplifier rated at 40 Watts per channel minimum.

That amplifier with be dynamically limited and will not work very well with those speakers.