I'm hoping I can get some advice. My current audio setup is a Monitor Audio A100 hooked up to a pair of B&W 685 S2 speakers. I mainly use AirPlay and the optical input from my PC, also occasionally DLNA to steam FLAC files from my NAS. The A100 sound quality is fantastic and very composed. However I have recently been feeling that I would like a little more bass with some music - nothing excessive though. I was wondering whether replacing the A100 with an amplifier that has dedicated bass and treble controls would be a way forward? I was looking at the Yamaha R-N402D. This is classed as a 'network receiver' rather than an amplifier, however from what I can see, it is both. It also seems to have all the connectivity of the A100 with the addition of Bluetooth (with AAC support), a radio (FM, DAB and internet) and quite a few other features. My questions are: 1. How would the Yamaha R-N402D compare to my Monitor Audio A100 in terms of sound quality? 2. The Yamaha is classed as a network receiver - I always thought that a network receiver was a separate component that you hook up to an amp. As this is an integrated device - would it deliver inferior sound quality? 3. Are there any other amps that I should consider for £300-400 - I don't mind buying used either. Thank you.