Sennheiser HD58X - Oluv's neutral target EQ (Patreon)

Here you can find my recent EQ for the Sennheiser HD58X with more or less fresh pads. I was using this headphone intensively since I got it in May, thus it should work for brand new units quite well. This EQ should represent "true neutral" sound with this headphone with no obvious bass or treble boost. Just the same response you would get from neutral speakers placed nearfield and equalized for a flat response at listening position like described in my neutral target post.

Compared to my previous V1N version (green) this EQ sounds more correct to me. Both side by side, you can see that they mostly differ in a slight upwards tilt towards treble for the new version:

The EqualizerAPO file has additional 2 filters which you may want to apply to simulate some kind of "in-room" response. There is some slight bass boost and a slight treble reduction which I personally can still accept, more bass boost and more treble reduction would appear to boomy and muddy to me. Below you can see how my flat EQ and with both filters active will measure on a proper GRAS system together with the HD58X unequalized in grey:

Instead of my filters you can also try to apply the "trained listener speaker target" by Floyd O'Toole on top of my flat-EQ which I attached here as well. For me this becomes way too dark and fat sounding though although it may simulate the in-room-response of a speaker even better. Below the target curve:

This may result in a slightly closer response to Harman especially with mids, although even with Toole's target applied it will still have less bass than Harman (black my flat EQ, yellow with Toole's target applied) :

Last but not least the Qudelix 5K setting, which I adjusted slightly to get more or less the same response which I get from EqualizerAPO. The resulting sound is still less smooth from the Qudelix. Listening to pink noise just doesn't have this smoothness I get from the PC. This may be a result of Bluetooth compression or the type of filters used, but Qudelix definitely sounds more digital to me.

With Qudelix you still have a spare filter left which you can use to adjust treble or bass to your liking. If you like more bass, you can also start by moving the first filter slightly higher from 28hz to 35hz or 40hz.

Please give the EQ some time to get used to it, as it will definitely appear way brighter than the stock HD58X at first, but my EQ should sound more correct and also be able to offer you far more details and a more realistic sound stage. I expect your valueable feedback soon particularly to know how others perceive it and how I could improve for future.

Update: I tweaked my previous setting to get a smoother and even closer result compared to the speakers. As visible from the measurement done with my ears, I am closer to the spectrum of the speakers now, especially in the treble area, but I still deviate in some parts, although trying to match these closer by graph made the final result sound more off.

I also had to sacrifice the spare 2 filters. Maybe I will manage to rebuild the response with fewer filters in future. Neither did I try to optimise a setting for the Qudelix yet, please find V3N attached. Curious to hear how you will perceive it. The overall timbre is very close to what I perceive from the speakers now. With music it sounds really alike, with pink noise, I can still hear some slight Hhhhh from the speakers which I couldn't reproduce properly with the headphone. I think in this regard I am a bit closer with the Free Pro 2, but the HD58X sounds slightly more airy and bass seems more realistic than from the IEM.