What are the a6as like? I have a 1080 advantage and it's built very well. I found the room correction useless tho. I think it sounded very musical with simple manual adjustments. I keep it here as a back up but honestly prefer the Denon.
I came from a decent two channel system and choose the A6A to build a multi channel system. Main competitors for me at the time was units from Marantz, Denon, Onkyo and Pioneer.
I was, to be honest, a bit worried about sacrificing 'sound quality' but the A6A surprised me in a positive way when I first ran it with my fronts. I had an ESS Sabre based DAC in my old two channel system. The A6A utlilize two ESS Sabre DACs (ES9026PRO for the mains and the ES9007S for the rest). I don't know to what extent that influence my opinion on the sound, but I am very happy with the sound, I find it neutral, clean, detailed and rhythmic to drop a few buzz words. It doesn't have a distinct sound character, it is neither warm nor bright.
I have only limited experience with other room correction systems like Audyssey and Dirac and I have never experienced the old YPAO version. As far as I can tell the new YPAO version is a new design and quite different from the older versions. I like YPAO in the A6A, it does a good job of making the system sound coherent and it takes care of the most important room issues automatically. The manual PEQs are there after calibration if needed.
I'm way more into audio than video, but as far as I can tell the video section performs well and I have had no problems or complaints there.
In general I find the A6A well engineered with a high degree of usability. It seems however, to be somewhat underrated in social media and such imo.
Some of its strengths:
+ Very solid build. It has a sort of no-nonsense approach to it, focusing on stuff you actually use instead of a lot of bells and whistles (well, the DSP modes are a bit superfluous to be honest...)
+ It works nicely with 2 channel music as well as multichannel content
+ To have 8 scenes (user-defined presets) is absolutely awesome, you can define almost every available setting per scene (and there are a lot of settings ...)
+ YPAO room correction is simple to run and works very well imho
+ The web-based GUI is a superb way of fiddling with the myriad of settings available, I never use the front controls or the remote for that. Btw: The display of the unit is rather small, but it is actually a good thing in my mind, it is less intrusive that way and I don't use it for navigating settings anyway.
+ The PEQs and other manual controls for the speaker patterns are great if you want to make manual adjustments per speaker
Might as well take this oppertunity to list some improvements I would like to see from Yamaha for the A6A:
* Now there are two separate speaker patterns available holding calibration data, speaker levels, manual PEQs etc. It would be great with one or two more speaker patterns to be able to taylor the sound to more than two usecases
* I would like to be able to run YPAO for a subset of all speakers or for individual speakers. It seems unnecessarily cumbersome to have to run YPAO for all speakers if I have only added, changed or rearranged one or two speakers.
* HDMI pass-through when in stand-by seem to use the latest used HDMI input. It would be of great use for me to be able to set a default HDMI input to be used for HDMI pass-through when in standby. E.g. my wife does not want to fiddle with the home theatre system at all when just watching TV, but the digital TV-box is not always the last HDMI input used when setting the A6A in stand-by.
* Adding a low/high shelving filter option to the PEQs
* Would be nice with a biquad filter option for all speakers and subwoofers to be able to import filters directly from e.g. REW for the tinkerers out there
* I do not use the DSP options much, for me other functions could probably use that space better
* MQA support!
* I like to uncluttered front, but for future versions of the HW, a HDMI input on the front would be nice