I personally think that you will get lower-end reasonable sonics with your Cinenova Grande 300 watts per channel HT amplifier but this amp will not bring out the best of the N802 since it wasn't made to drive a load as difficult as the N802. I looked @ the Cinenova Grande 7-ch amp & noted that they used a 4000VA transformer divided equally amongst 7 channels. According to my calculations that amounted to 10A per channel. This 10A needs to be further divided to 5A per positive supply rail & 5A per negative supply rail. That's an OK amount of current for most other speakers but quite a bit shy for the N802. You'd need an amp with double the current delivery to make the N802 shine. My assumption is that your 5-ch amp is not better than the 7-ch (which had more info for me to work with).
However, your goal might not be to make the N802 shine; your goal might simply be to be a N802 owner. I don't know what your motivation is to get the N802....but your present amp will give you OK-OK performance. The N802 is a challenge to drive - my friend could not drive them properly with a Classe 400 in a 2-ch setup.