05-08-15: GammajoThe "Is DEQX A Game-Changer" thread is essentially current, and is on-going. If you want to consider DEQX, and you haven't already seen that thread, I would consider it to be required reading.
Looking at room correction and all the threads I found seem old.
Also, for background on loudspeaker time and phase coherence I would commend last year's "Sloped Baffle" thread to your attention. (Bob R., as you'll realize speaker time and phase coherence, as defined in this post, are unrelated to absolute phase (i.e., polarity), to which you were apparently referring in your post. And time coherence is something that only a very small minority of speakers inherently achieve, and is something DEQX attempts to correct via DSP prior to implementing room corrections).
05-08-15: Zd542ZD, I would not extrapolate anything regarding DEQX or many of the other processors that have been mentioned from your experience with the Behringer or dbx units. As someone having considerable proficiency with computers, I'm sure you realize more than most that DSP and computer technologies have advanced by leaps and bounds since those devices were introduced. And although I'm usually among the first to caution people that in audio price and performance don't necessarily correlate, I think it says something that the flagship DEQX HDP-5 model costs well over 20 times as much as the Behringer.
I do base my opinion on actual experience, and not just guessing. I have a Behringer 24/96 digital EQ that destroys the sound of my Wadia CD player. I also have a dbx analog EQ that ruins the sound of whatever preamp it gets used with. So, in my opinion, the OP's Ayon CD player is just to nice a player to be run through processing.
I have an HDP-5 on order, BTW, which I will be receiving soon, and which will replace my preamp in addition to providing speaker and room correction functions. I ordered it from Nyal Mellor of AcousticFrontiers.com, who has a great deal of directly relevant expertise, offers a free webinar/walk through on the use of the associated software, as well as unlimited phone and email support. And both he and the DEQXpert service Roscoe mentioned can perform the entire correction process on a paid basis, via Skype. Nyal also provides 30-day return privileges, which I have no expectation of having to utilize. I will be chronicling my progress and findings in the "Game-Changer" thread.
Inputs to that thread from several A'gon members having both extensive DEQX experience and very high quality systems, including Psag who posted above, were among the major factors which have given me sufficient confidence in both the transparency and the effectiveness of DEQX to proceed down that path, given that a hardware solution best suits my particular circumstances. Kal's (Kr4's) review in Stereophile was also helpful.
Regards,
-- Al