Sennheiser HD58X - Oluv's natural target V1X EQ (Patreon)

I decided to leave the HD600 aside for now instead of starting to swap pads back and forth, as even unmounting and re-mounting the same pads can change the response significantly. So far I managed a usable sound for the HD600 with my current settings, which I don't want to mess up now, therefore I started to work on the HD58X instead. This is a brand new unit which I ordered from Drop, thus pads and everything is completely fresh, keep that in mind. If your unit is older or the pads more worn, the sound will also be different than what I intended.

To my surprise the HD58X sounds very muddy in its stock form, I wonder how I could recommend this back then, but actually I didn't even know how a headphone should really sound some years ago, it's still a bit shady to me and although I am trying to make them sound "correct" it's just my own interpretation based on measurements done from speakers and trying to match the response of the headphone as close as possible and verify by listening that it sounds close enough.

I managed a first setting for the HD58X which I am quite satisfied with, it definitely transforms the headphone into something way more highend sounding than its stock state, the difference is quite shocking, if you are used to the muddy sound of the HD58X you will probably consider it too bright with my EQ, but this is actually how speakers are perceived by my ear. Below a comparison of my EQ compared to stock in green:

you can see that mids above 2khz are missing compared to what is perceived as "neutral", also treble above 13khz is lacking. Here compared to the HD600 with V4.1X in blue also overlaid with my reference spectrum:

You will notice that I had to adjust some areas for the HD58X compared to what I did for the HD600. Thus the area at 2.3khz is slightly lower now, and the treble around 10khz is also different, but I didn't want to mess with the original response of the HD58X too much in this range, I tried lowering this 10khz peak, or shifting it closer to what I get from the HD600, but it sounded wrong. Thus this so far is the best compromise I managed and I think the sound is pretty similar to the X3000 with these settings. There may be some slight fine tuning necessary, but I already sat for several hours trying to get the entire frequency range into a correct balance as possible.

I am not sure which I like more, the HD600 with EQ or the HD58X, but honestly I perceive the HD58X as smoother and more real sounding, closer to the speakers, while the HD600 seems slightly more spacious and less tunnel-like, also a bit more relaxed, although I only compared them with the HD600 playing from the Qudelix, which again changes the response a little bit. Maybe the difference in sound is a side effect of new pads and the driver being farther away from the ear and a much higher clamp force for the HD58X which simply gives another perception of sound, this may be also the reason why I had to boost 2.3khz more on the HD600 to get a similar perceived response. Sound perception is not an exact science, therefore I can only approach the optimum bit by bit by hearing and analysing the measurements if there can be valid like this.

I just received the KH80 today, I will set them up and use these as reference for all my future work from  now on. Thus my current target my need some re-adjustment to an even more neutral source than the X3000 was. All this will follow by and by. I am heavily dependent on your continuous support to allow doing all this, right now I cannot even afford paying for the KH80, therefore I am thankful that Max sent me them like this for now.

All HD58X owners, please let me know how this EQ works for you. The "transformation" should be quite drastic in this case, therefore I am really curious to hear your opinion. I will also try to also cover the HD6XX next together with the HD58X.