introducing an appropriately priced av amp?

I would avoid Yamaha.  The grounding techniques they use (or used to use) doesn't work well with Naim. I went through a very time consuming exercise trying to integrate my first Naim Amp (NAIT 5) with a Yamaha receiver. Ground loop hum. Gave up and switched to Denon in the end, which worked (and still is working) with no issues.

I will caveat my response by saying this was about 10 years ago, so Yamaha may well have changed their design since then.

I would avoid Yamaha.  The grounding techniques they use (or used to use) doesn't work well with Naim. I went through a very time consuming exercise trying to integrate my first Naim Amp (NAIT 5) with a Yamaha receiver. Ground loop hum. Gave up and switched to Denon in the end, which worked (and still is working) with no issues.

I will caveat my response by saying this was about 10 years ago, so Yamaha may well have changed their design since then.

You don't give much detail about 5.1 or 7.1 etc or a budget. However, you may wish to consider a separate processor and amplification. You may also get more comments if you posted in the Home Theatre section.

I know that you already have a Blu Ray player. However, with a budget of £2000, you may wish to consider the Oppo 105 Blu Ray player at £1000 as a combined player and AV Preamp. That then still leaves you £1000 for the power amplification. You will see a thread on here about it a little further back. It depends on what connectivity and functionality you need though.

Alternatively, the Audiolab 8200AP at £1200 may be worth considering as a pure audio processor, plus power amplification. The only caveat there is that your BD player must be capable of transcoding DD and DTS Hi Res soundtracks to 5.1 PCM via HDMI. Most players will do that though.

To be honest, there are quite a few avenues open to you with that budget. You would be able to find a s/hand or maybe late ex-dem NAP V175 three-channel power amp for the centre and two rears if that took your fancy I suppose. I guess finding a timbral match for the centre is important, so someone with knowledge of your Olive kit may be able to offer better advice.

Moving into AV always has little frustrations and a bit of a learning curve in some respects too

Any BD player would of course need multi-channel analogue out to feed the AV2 in order to utilise the BD soundtrack HD Audio codecs. I know many people very much respect the audio qualities of the AV2 even now. I can see how it might well sound rather better than many of the AV Receivers around, where we are paying for a lot of features and video processing that many of us don't need, rather than paying for a concentration on all-round audio quality.

Some people would say that if you're spending that amount of money, you should end up with an up to date solution that properly processes DD THD and DTS MA though. Having said that, I'm still doing it the analogue way into a Meridian G61, but I'd probably look for an up to date solution if I were spending now. Still, it would have to give me better sound or there's no point.

It's only my opinion, but I would certainly want access to the high definition soundtracks of Blu Ray if I were implementing a multi-channel solution. They are substantially better than the lower resolution vanilla DD and DTS equivalents and part of the Blu Ray experience.

Therefore, if utilising an AV solution like a Naim AV2 or a Meridian G61 (like me) or many older AV amps/receivers which do not have HDMI, you need a Blu Ray player with 5.1 or 7.1 analogue outputs on the back. The Hi Def sound is decoded in the player to multi-channel analogue and then sent to the matching inputs on your, say, AV2. Purists will say that it isn't going to get you the best experience compared a dedicated HDMI solution, but it's still pretty good if your player and processor can do their job well. I kind of consider the Audiolab 8200AP as the up to date spiritual successor to the Naim AV2, albeit that a Naim version would have had perhaps some more attention to build and detail, but at a much higher price of course.

The AV2 can certainly do it's job well, so any weakness would be based around how well the digital to analogue conversion was done in the player. The video aspect of even cheaper players is pretty good with Blu Ray discs these days, but some players may lack something in the audio department in terms of conversion (many of the cheaper ones simply don't have the facility anyway), so your choice of player becomes a little more important if you go down this road.

It's only my opinion, but I would certainly want access to the high definition soundtracks of Blu Ray if I were implementing a multi-channel solution. They are substantially better than the lower resolution vanilla DD and DTS equivalents and part of the Blu Ray experience.

Therefore, if utilising an AV solution like a Naim AV2 or a Meridian G61 (like me) or many older AV amps/receivers which do not have HDMI, you need a Blu Ray player with 5.1 or 7.1 analogue outputs on the back. The Hi Def sound is decoded in the player to multi-channel analogue and then sent to the matching inputs on your, say, AV2. Purists will say that it isn't going to get you the best experience compared a dedicated HDMI solution, but it's still pretty good if your player and processor can do their job well. I kind of consider the Audiolab 8200AP as the up to date spiritual successor to the Naim AV2, albeit that a Naim version would have had perhaps some more attention to build and detail, but at a much higher price of course.

The AV2 can certainly do it's job well, so any weakness would be based around how well the digital to analogue conversion was done in the player. The video aspect of even cheaper players is pretty good with Blu Ray discs these days, but some players may lack something in the audio department in terms of conversion (many of the cheaper ones simply don't have the facility anyway), so your choice of player becomes a little more important if you go down this road.

Thank you Rackkit. Clearly a second hand version is the only AV2 option and in truth I am warm to this. Are you aware of any reliability issues ? would an older version require a re-cap or any other type of maintenance?

I do know of an AV2 and partnering NAPV175 from a trader in the south of the UK at sensible prices, so they are 'out there'. Obviously I don't think I can say any more on here, as it would break the rules. Maybe I already have

Am I allowed to say PFM ?