Need your recommendation on a 5 or 7 channel amp

I'm new to this site and need some recommendations on 5 or 7 channel amps. My current home theater system consist of the following:
  • Sonus Faber - Sonetto III front speakers
  • Sonus Faber - C1 center
  • Sonus Faber - in wall rear 562
  • Marantz AV 7706 processor
  • Golden ear XXL sub
  • Sony 325ES projector
  • SI screen
Amps that I'm looking at are as follows and would like some input which to get or other recommendations:
  • Parasound A52+
  • Parasound A51
  • Audio Control Savoy G4
  • MarantzMM 8077
Thanks for your help!!
Likely current capability.  The AT182x series uses smaller power supply capacitor banks and I don't think it's a fully balanced/differential amp (it's a single-ended amp board instead).

AT1820: 22,400uf power supply capacitance per channel, 4 output transistors per channel

AT4000: 46,200uf power supply capacitance per channel, 12 output transistors per channel

AT6000: 59,400uf power supply capacitance per channel, 16 output transistors per channel

In laymens terms, the transistors are what generate the output voltage/current required to drive the speaker.

The AT4000, being a fully balanced/differential design, will have a stronger control over the speaker drivers and likely have more punch/drive when compared to AT1820.  The bigger power supply of AT4000 will result in stronger bass/midbass and also smoother audio through the rest of the frequency range.  That being said, the AT1820 series is likely still better than the Savoy G4.
I can get a pretty good deal on the ATI4027 @ $3960 and the ATI1827 @ $2400, but with out previewing either one which would you prefer? Sonically will I really hear the difference between these and with a $1,560 price difference do you really think it's worth it, or should I entertain an ATI 4023 for the front 3 speakers and an ATI 1824 for the rears and Atmos speakers predicated the cost is the same as the above configuration as the ATI 4027? Buying with out previewing is my biggest concern. Thanks!!
Ordered ATI 4007 amp. Will let you know when I receive and how it works in my home theater. Still waiting on the Marantz AV 7706 processor - think it comes in end of November. Thanks again for your input !!

I've also been in the market for a new center and surround amp.  I was set on buying a used Theta Dreadnaught II or III.  After talking with my shop for a while today, I was convinced that the new ATI AT-3300 series that was released today.  Supposedly it is the better option.  It's half the price of a new Theta, and supposedly a better sounding amp.  When I asked if I am giving up anything from the AT-6000 I was told no, the new 3000 series is everything the 6000 is and more. So I ordered a 5 channel version and will have it possibly by the end of next week.   There is zero info on these as only a handful of people have them, so I am going strictly on the word of my dealer.  As of today, they are not even on ATI's website yet.   

I'm currently running PS Audio BHK 300's for my fronts and was running a McIntosh MC-207 for surrounds and center.   I'm only going to be using the ATI for HT as all my music I listen to in 2 channel.  Once I receive it and burn it in, I'll report my opinion of it.  I'm very curious how it will compare to my BHKs on my Kef Reference 3's.  I have a feeling it may be a touch bright, but I will soon find out. 


For comparison my system consists of:

Lyngdorf MP-60 2.1, BHK 300 monos, Kef Reference 3, Kef Reference 2c, Kef R di-poles, Kef R5, JL Audio F 113 V2 (2).