Go get out your pitchforks, I’ve done a sacrilegious thing. . .

Like some here have suggested you should have done several things before you tried the eq. First off, I would suggest demolishing one end of your house, then rebuild a room with soundproof double walls for a dedicated audio room with top notch wiring and electrical outlets, don't forget power conditioning. Then self flog for buying a house that didn't have the acoustically perfect room. The next step is to plaster all the rooms in your house, including your bathroom with sound absorption  panels. After this, self flog again. Now if no perfect sound from your audio rig, add hearing aids. Another self flog. The last step is the EQ.

Hey, if you’ve voiced your system and there is zero room for improving it or the room then I guess you’re lucky and will never need to upgrade. However, I’ve never been able to achieve perfection, but I got a whole lot closer with one component - go figure! And it only took 5 min.

also for those talking about adjusting for ever song, do you change out cables or equipment for every song?  You know you can just adjust it for best overall sound and forget it. Very easy!

My 2 cents on readjusting the EQ for different recordings - I've had little luck with that. I consider that a good thing. When I get the system response correct pretty much everything sounds better. 

Why would one have desire to add eq to system if not needed, no inherent requirement audio systems have to have extra eq applied via dedicated eq. Therefore, eq would only be effective purchase for me if eq applied to each recording.

If adding eq for system balance, something in system not meeting your sound preferences. One can achieve system balance through various means, I prefer not doing this through add ons. I associate add ons as band aids, this being the need to repair something upstream or downstream of equalizer.

I suppose if I did have need of eq, I'd be far more likely to apply dsp via something like HQPlayer, rather have it in software vs hardware.

I get it. You don’t like EQ’s. Not sure that’s relevant.