Prof Peng, subjectively, does the 70 sound more musical?
Or does it sound the same and basically no difference if room correction is done well?
You tweaked the heck out of both them so genuinely interested if there is a difference with the better DACS and circuitry etc.
I don't want to mislead anyone, so I would only say imo the AVM70 will not make sound quality worse, or better than others that offer similar specs and measured well. The AVM70 will just amplify the signal with minimum distortions and added noise. Specs shows, and verified by ASR's measurements that it is way better than the Marantz AV8805A, though likely not as good as the Marantz AV10 that is listed for 2X the price.
As far as "musical", that's a tough one, because everyone's definition may be different. My reference is live classical orchestral music in concert halls. Based on that, I find the AVM70 musical, but again other's definition may be different. That's just my subjective view, if you look back to the specs and measurements, distortions+noise of this thing is so low, between about 0.001% at 1 kHz, 4 V balanced output, and no higher than about 0.007% at any frequency in the 20-20,000 Hz range, it really is well below the threshold of human audibility including self proclaimed or proven golden ears.
If we turn to the most transparent preamp processors currently available, I would bet it is the Marantz AV10, based on available bench test results, but based on specs and projection (reference to the AVM70 that we have the measurements for), the AVM90 will most likely measured better than, or at least equal to the AV10's.
Based on known science (yes there must be things we don't know) anything that has better specs and measurements than the likes of the AVM70 is not going to "sound better". I did audition then AVM90, as the dealer were trying to spend more money obviously, by telling me the 90 sounded much better. To my surprise, I did not feel the 90 sounded any different, based on their demo movie, after about 15 minutes of listening carefully. Actually, I couldn't even say it sounded any better than my Denon AVR. That just means to me that there isn't much point trying to choose a sophisticated feature rich gear based on perceived sound quality in dealers demo room. There isn't enough audible difference to overcome the other factors such as the inability to compare AB quickly (memory issue), level matching, and obviously the different room acoustics, speakers, placement etc.
Anyone can say anything about sound quality difference, but unless you sample hundreds of people and they all (or the vast majority) tell you the same thing, you wouldn't know who and what to trust anyway.
To conclude on your "more musical" or not question, if I were to answer in one word, it would be a qualified "yes", but the devil is in the details as I alluded to in the above lengthy paragraphs.
By the way, it is true that I tweaked the deep bass/room gain settings for hours, and managed to achieve very decent FR in that range, but I really couldn't hear that much of a difference between with ARCG on and off, so everything I commented above on sound quality, are applicable to with ARCG, or without. This thing sounds very good without using room correction, subjectively, to me anyway.
If we are to narrow things down to movies, instead of two channel stereo music, I definitively enjoy the AVM70 more. In complicated scenes, I felt the overall sound effects have better clarity, therefore more pleasing to my ears/brain. This is highly dependent on auditory memory as there is no way to do any sort of AB comparison.
An example of many alternate subjective views for you is right here on Audioholics. If you watch the Audioholics/Audio advice video on the AVM90, Theo, the owner of the AVM90, emphasized he heard much better sound quality when listening to music, so his subjective impression is totally opposite to mine, but then his is the 90, and mine is just the lowly 70, so I can't say much more about our opposing views.
If you are still on the fence, and if the AVM70 has the features you need, then the AVM70 probably is an easy decision if price is an important factor. That's because most of the known bugs are fixed, and at the moment, there just isn't anything comparable in terms of specs and measurements, based on current price points. Keep in mind that not long ago, Anthem had the 70 on sale for about 15% less, so I think they will do it again between now and Christmas.
*Cautionary note on the SINAD based chart below
: ranking is based on SINAD (99 dB in this case) measured at 4 Vrms balanced output, with test frequency 44.1 kHz, and input test signal at 0 dBFS. Many will, and have said so, that ASR is obsessed with SINAD. While that is fair comment on its own, I would offer my personal observation below:
Based on having seen so many ASR bench tests, and I could include those done by Gene on Audioholics as well, there has been a clear and consistent trend, that indicated if this particular test shows very good results, the other important test results such as IMD, SNR/DR, cross talk, FFT (harmonics profile/structure), linearity, 32 tone input, jitter, frequency dependence, would generally, looked very good as well, with few (if any at all) exceptions.
Also, since the unit ASR measured was from the fall of 2021, so it may be possible that the DUT is one of those early batch that has the AK4490 DAC IC, instead of the ES9038 Q2M used in those manufactured during the shortage of the AKM chips after the factory fire. I have compared the specs of both ICs, and found negligible difference so I am very confident that regardless of the IC used for the DAC, the test results would have been the same.