Yesterday I went through both reviews as well as some Dirac reviews (though they were much less thorough than the above two).
It was very enlightening in how the fundamentals of ARC's eq works and how it affects overal performance. I really liked how the result is proven in the article and takes you step by step through this process. Excellent in-depth knowledge.
The most interesting part to me however (comparing it to Dirac) lies within the "Time domain correction". The time domain correction is disputed vigorously by the author (David A. Rich). I unfortunately have no access to the mentioned book ("Sound Reproduction, Loudspeakers and Room") to investigate on why Time domain correction is controversial.
When looking into Dirac Live and the (aforementioned) interview, it seems that Time Domain Correction - which seems to be happening on frequency level - could have significant impact in that it makes it possible to make sure the sound produced by each woofer (not speaker as a whole!) can be effectively corrected so it would give a correct reproduction of the impulse.
My guess would be that overly correcting the impulse response (so you will, at the listening position, hear every frequency exactly at the same time) would be wrong, as sounds produced in real life will have inherently different delays. In my opinion the correction should only be applied as to correct for differences in woofer responses (correct the subwoofer for its delay in comparison with the mid-range woofer and the high range tweeter, and every other sound producing item in between).
Originally Posted by DS-21
The beauty (or curse) of Dirac is that the user can draw her/his own target curve. In that respect it’s more flexible than ARC (or gives more rope for purposes of hanging…).
As someone who uses both correction systems daily (albeit in different configurations; ARC in multichannel and Dirac in 2-channel/nearfield) here are my thoughts in the context of well-optimized systems with speakers that offer constant directivity and (in the multichannel system) multiple subwoofers: both are, IMO, (a) comparable, and (b) substantially better than the current competition.
Given the price difference and my suspicion that all the forthcoming AVRs/ampless-AVRs with either system will have the same handicap (no Dolby Volume loudness compensation above 7.1-channels), the new Anthem seems to provide the most value IMO.
I’m not sure I hear much if any difference from Dirac’s mixed-phase equalization, but the speakers I use in both systems are by design more coherent than most home audio loudspeakers and I strongly prefer to limit correction to the modal region and below.
Thank you Sir, for your in depth response!
To sum up your points (if I understood correctly):
1. Dirac is more flexible in targeting specific needs (you can choose your own target curve)
2. In your experience both perform equally well. Both being (far) better than the competition.
3. However there seems to be a slight difference in near-field equalizing (though in regards of this thread being a home theater oriented one, I guess near-field would be less of an issue)
4. Due to your experience with higher end speakers the "mixed-pahse equalization" (am I correct that you are refering to the equalizing in the time domain / impulse response?) your take on this would be that it has significantly less impact on the overall performance
Lastly a question; you mention you would go for "ARC having an edge over Dirac in regards to their price positioning". When comparing for example an Anthem MRX 720 and an Arcam AVR 550 (which has Dirac incorporated in its AVR). Pricing seems comparable (at least here in Europe), would that alter your perspective?
To me the choice between an Anthem or an Arcam is still not as clear cut as I had hoped. Im still going back and forth. Both having pro's and cons (depending on if you look at: rated power per channels, support for eq on all channels including heights (atmos), Impulse response EQ, Frequency Response EQ and ofcourse pricing)