To Equalize or Not to Equalize

If you are open to getting a used EQ I can recommend a DBX 10/20 Equalizer. It is a 10 band EQ with memory settings so you can save and recall several different profiles. The unit also has a real time analyzer but you would need to find one where the owner has the original microphone. I have two of these, a 14/20 for my main system and a 10/20 for my desktop system. There are usually a few of them for sale on eBay selling for $400 to $800 depending on condition.

First, get REW (it's freeware) and a calibrated microphone (e.g. MiniDSP umik-1). Take in-room measurements for L and R channels independently at your listening position. These and other measurements will reveal much about your acoustics that you may not be aware of presently. It's a no-brainer.

With those measurements, you can compare your response to the Harman and NAD target curves (they're very similar), and you will have a solid idea of what to do with EQ settings. Without those baseline measurements that serve as your point of reference, you're playing "Pin the Tail on the Donkey." If you know what that is, then you'll understand the analogy. REW allows one to dial in the appropriate settings for each channel. 

I used a dbx 2231 graphic EQ for a long time with very good results, which is an economical and reasonably transparent platform with 31 octave resolution. Accuphase used to make a nice graphic EQ (G18), and examples in good working order remain expensive. There are boutique, studio quality graphic and parametric EQs that are very good, some being certainly better than others. The downside is they all insert another cluster of pedestrian electronics and additional connections/cables into the signal path, and some degradation (e.g. soundstage) tends to become apparent if the system is resolving enough. 

If you use a digital platform that supports inserting a text parametric EQ files for headphone or speaker correction, then you are in luck because REW can use your L and R measurements with a target curve of your choosing to generate PEQ files that will put you on target. I eventually found this to be the superior in terms of integrity and sound quality and I cannot see myself ever returning to a hardware EQ.

I have experimented with both 10-band PEQ/GEQ in the digital domain and the bass/treble tone controls on my Cambridge Audio Azur 851A. Although I was able to adjust the SPL curve to closely match the target (desired frequency response), I was still not satisfied with the resulting sound quality.

In my system, the improvements achieved through analog cable and preamp upgrades were more satisfying than those obtained through EQ. This can be illustrated in two main areas:

1. The treble produced by EQ was less edgy, but it was not as smooth and refined as what I experienced from the cable and preamp upgrades.
2. EQ added more bass weight / presence, but the cable and preamp upgrades also delivered more nimble, textured, and bouncy bass.

As a result, I ultimately abandoned EQ altogether and have no intention of revisiting it.

Another vote for Schiit Audio.   I have the Loki EQ and it is amazing and doesn't break the bank.  Less than $300 and it allows me to fine tune the sound to my ears.  I'm not sure you need to spring for their top of the line $1,600 Loki Max, but you'll love the Schiit out of whichever you get.

...and I'm Still notabot....😒

Been Eq'er since a Audio Control C-101 into L-07 Kenwood system to the ESS Heils. Mic for the 101 was the size of a medium lipstick, disappeared in a stand.*L*  

Still have a pair 8024 Behringers' doing what I want whatever. A pair of their mics for same.  REW and all sorts on the 'puter....that, and multiple pairs of drivers....
Moving lock, stock, and the 50 lb. amp to another home with its' drawbacks.

Think I'll have some Sub Fun in the sun.  Loosen the windows a tad....