Marantz 8802a > looking for better two channel


Curious on people’s opinions and experience. I started out more into home theater but recently have been getting more into two channel. I’m running the marantz biamped into lexicon RX-7 into revel studio 2s with a pair of JL Audio fathom f212v2s.   There are basically no places to demo equipment where I live but I’m curious what level of two channel preamp it would take to be a significant improvement over what the marantz is doing. I’m running an oppo 105 with balanced connections as the main source.  While this may still be awhile out I’ve considered McIntosh mx150, lyngdorf Tdai-3400, or shoot for the moon one of the Current levinson preamps.  Also wondering if switching to any of those would then require a new amp to fully take advantage.  I plan to keep the home theater setup and do a pass through while keeping the subs in for two channel.  I like a pretty varied mix of music so not looking something thats great with classical but terrible for rock for example.  
esthlos13
I've been curious about the Lyngdorf myself.
PS Audio, Simaudio Moon, Parasound Halo are a few brand names off the top of my head; that won't disappoint.
I always liked McIntosh too, but I don't have the space.
The Lyndorph is not even distortion free for 16Bit. 
 
I doubt you will hear any benefit in “upgrading”. The target Audyssey curve isn’t that great, if you use it and don’t use Dynamic EQ, activate it, but change the Reference Offset from 0dB ro 5dB or 10dB.
If you get a quality stereo amp or monoblocks and a good preamp, there will be a very noticeable difference in sound quality. I went from a Marantz 8801 and Lexicon LX-7 to a Modwright LS-100 and Wyred 4 Sound st-1000 mkii (since replaced by rogue audio M180 monoblocks) and the improvement in detail, soundstage, etc was not small. 
The Marantz AV880x processor line are very nice pieces.  They have excellent power supplies and audio circuit design.  The sound is very solid and very full and very natural.  However, being Marantz, they are voiced very warm, which means the high frequencies are definitely rolled off compared to other preamp/processors.
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The Lyngdorf is not going to be warm at all.  It is a very high resolution device.  However, when compared to Marantz, I think it might sound just a little bit thin and not quite as natural. 

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I haven't directly heard the McIntosh, but I suspect it may be somewhat in the middle.  More natural sounding than Lyngdorf, and more high frequency resolution than the Marantz.
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You may want to look at Krell Foundation.  That is also a very clean sounding modern processor.  My suggestions are all based on the assumption that you are looking to keep a HT processor in the mix and not go to a 2-channel only system.