I have an Onkyo TX-SR806 AVR. I'm looking to add an amplifier to my set-up. If I add a power amp with a similar power rating of my AVR (my AVR is rated at 135 watts/channel) will I notice any improvement in audio quality? My AVR is a "high current" receiver (rated at 7.8A). I listen at moderate volume levels. I'm also using a powered sub, which helps to take the load off of my AVR.