Stereo power amp for $10k

At this price range, You may add BAT VK-600SE or Vk-650SE (used one!) to your wish list. You speakers are pretty good. I heard Pass labs X250.5 and Pilinius amps in the shows, they are very good. However I found BAT vk-600se to have a better resolution, dynamic and especially much better Bass with a more defined control of the sound edges. I also tried Krell EVO402e which was very good too but its sound is too analytic and cold, even thought it has an excellent bass.
That's why I ended up with BAT vk-600se which its sound is also more on warm side of neutral. It is obviously based on taste and is all system dependent ...

good luck.

I was trying to be diplomatic, but am glad others are being more direct.

It is an absolute waste of money and stellar equipment to put a near reference level $10k amp and your speakers behind a mass consumer grade AV preamp/processor. None of the subtle nuances, resolution, imaging, etc, etc will make it past the preamp, no matter how good the rest of the system is. Your preamp is an insurmountable bottleneck.

As pointed out above, you would be far better off buying a dedicated $4k 2-channel preamp and a $6k amp. Then, just switching the amp inputs when you want to listen to HiFi. It would only take a few seconds

You seriously have great speakers that deserve far better than a consumer grade AV preamp

Yes - the Marantz preamp will limit performance, but there is something else to consider. Especially since your speakers are relatively efficient.

I have a lot of experience with Pass amplifiers (we currently own 5).

First, there is a very significant difference between a X-150.8 and a X-250.8 (the 250.8 is much better).

Second, there is even a bigger difference between the X-250.8 and the XA-30.8. The 30.8 sounds better, much better! I've listened to and compared both of these .5 series amplifiers and we used a 30.5 on our main speakers instead of our 250.5 in a relatively high end system - until we upgraded to our current XA-200.5's.

The only thing the 30.8 will give up to the 250.8 will be the dynamic impacts of bass. Like the dynamics of a drum. Sustained bass notes will be fine. Everything else will be much better with the 30.8. Don't take my word / experience for it, call Pass and ask them this for yourself.

Better yet, find a Pass dealer and listen to the X and XA amplifiers before you decide. It would be worth investing a weekend of time and travel to do this.

IMHO - upgrade the amplifier to a 30.8 and down the road get a good analog pre-amp with home theater pass through. We enjoyed our 30.5 for 3 1/2 years before upgrading to our 200.5's.

Each upgrade will be like listening to a new system. And you'll continue to enjoy your music along the way - which is what it's all about.

Yeah, have to agree with others this is a borderline insane idea, especially when it's so easy to just run the front L/R pre outs from the Marantz into a spare input on a good stereo pre. Then you have a true high-end stereo system embedded seamlessly into your HT setup. Let us know if you need more specifics on connections if someone else hasn't already provided them. I'd recommend buying something like a used Plinius SA103 and use the leftover $$$ to get a good stereo preamp. The reason for the Plinius over something like Pass is that, along with providing the sonic qualities qualities you're looking for, it has a low bias mode that you could use when watching movies or TV and greatly decrease your electric bill. Best of luck.

Tjassoc,
You make a very compelling case for buying the Pass XA-30.8 for this scenario, very logical.