Sonos Amp to drive front left and right speakers

Hi. What do you hope to gain, given that you already have an AV receiver? What would you connect the pre-outs to?
I am struggling to understand what you want to achieve, but maybe I'm missing something.

Hi thanks for your reply.

I’m looking to improve the quality of the front channel amplification using the Sonos Amp for music primarily and movies. My AV receiver would deal with the centre and rear channel amplification with the front pre outs feeding the line in on the Sonos Amp in movie mode. Music would stream directly to the Sonos Amp and front speakers

The line-in has a 70 ms delay that will make it near impossible to use in this manner.

Thanks. Do you know why that is?

Thanks. Do you know why that is?Yes - to give a buffer that allows perfect multiroom sync for music, which is at the heart of what Sonos is. As a more general point, Sonos HT solutions are designed to replace an AV receiver, not complement it. The delay is the most significant issue, but there are others. The line-in is designed for music sources so does stereo only, which is not the same as handling the front left and right from a surround sound format. Then there is the issue of possibly different tonal qualities of the two amplifiers. For me, the setup you are suggesting is a complete non-starter. If you want to use Sonos for HT, best do it in one of the ways it has actually been designed for.