I originally posted my EQ curves in the IEM forum, and since many of you don't use IEM's and probably don't visit that forum, I thought I should post the full sized headphone EQ curves here.
The original thread is here:
All headphones are referenced carefully against each other to "adopt" the strengths of the other models, and they are also carefully referenced against my Klein + Hummel O 300D studio monitors, which has been meticulously measured and corrected with the ARC System, working in conjunction with an acoustically fully treated studio, and additional EQ'ing on top of the ARC system to being the O 300D's to perfect flat accuracy (using a measuring grade mic and pro audio spectrum analyzers reading the pink wave response while EQ'ing in real-time).
EasyQ is a quality free equalizer that you can download from rs-met.com. I personally use J River Media Center 16 to host VST plugins natively, and Media Center currently has the most pain-free, intuitive, and powerful native hosting of VST plugins of all media librarians and players (all the other ones require third-party plugin hosts or awkward conversions/workarounds). You can easily recreate my EQ curves with any competent parametric EQ--just observe the number of dB's raised and the general shapes of each band used and try to reproduce them visually. I have tried using expensive commercial EQ's to do these curves and I really didn't hear any differences, so I just stick to EasyQ since it's so intuitive and easy to use.
Remember, all general EQ's are identical, and they can all be nulled against each other if you reproduce reverse curves exactly. The only times that EQ's sound different is when they were designed to have desirable colorations in the first place, such as emulating the harmonic excitement of certain hardware distortion, or the tube sound of certain legendary hardware unit, and so on. All the rest of vanilla/straightforward EQ's should sound exactly the same, unless the person who coded it is incompetent. What pro audio guys often pay for when they buy commercial EQ's is for the specific workflow/ergonomics, unique features, or desirable coloration. If those are not a concern, most quality freeware EQ's like EasyQ will do the job just fine, and are not "inferior." All of this is especially true if you know what you're doing (as in, you're not cluelessly destroying the fidelity of your audio by doing unreasonable amount of cuts and boosts, while f-cking up your gain staging by raising the entire gain of the EQ to levels of distortion). If you want extra assurance, you can always use linear phase EQ's, since they tend to be more idiot proof and they try to keep your phase coherent (although they are more resource intensive and are used mainly for critical mastering). If you are vigilant when you use normal EQ's and watching your phase relationships with analyzers, then normal EQ's should do just fine.
Voxengo's SPAN is an excellent freeware spectrum analyzer that also watches the phase, and is in fact so feature rich that it's a total steal for being free. I highly recommend it.
Here are my EQ curves for my main full-sized headphones (I didn't bother with the rest that I never use, and the EQ curves for the IEMs are posted in the link above):
LCD-2 - I don't normally EQ the LCD-2 for casual gaming or movie watching, but if I'm being a bit more critical, like for leisure listening or audio production, I would use this EQ curve (updated 2011-11-27):
This curve fills in the recess in the mids of the LCD-2 (for exmaple, it lacks the proper bite on musical materials with distorted guitars, brass sections), adds a little bit more definition in the treble, and restores the slight drop off of bass in the sub-bass region. Essentially, this curve addresses the issue of the LCD-2 being a bit dark in some people's opinion. While it adds some brightness and clarity, it absolutely does not make it fatiguing or excessively bright in any way (which is big pet peeve of mine. I hate ear-bleeding brightness), and IMO, strikes the perfect balance for my ideal sonic signature.
Since all LCD-2's are shipped with their individual frequency response graph, you really have to look at mine in order to put the EQ curve into proper context:
The thin white slanted line I drew is basically what’s widely considered the ideal upper-mids to treble response from 1KHz to 20KHz (headphones shouldn’t measure flat in that frequency range, since headphones are different from speakers), and I basically EQ’d the LCD-2 to that ideal (while also using test tones like sine wave at regular frequency intervals, pink noise, and comparison to other headphones and speakers). At this point, I would say my LCD-2 sounds about as good as I need a pair of headphones to sound, and beyond that, it’s just unacceptable diminishing returns.
If you are EQ'ing your LCD-2, don't just copy my EQ settings--you have to look at the measurement graph that came with your LCD-2, and then extrapolate from my EQ setting and my response graph to see WHY and WHERE I EQ'd in order to achieve the white line. Essentially, anything above the white line you want to cut, and anything below he white like you want to boost, so that the end result is as close to the white line as possible. This is more or less true for all headphones, so you can for example, take another headphone's frequency response graph and draw the same white line, and then proceed to tweak the EQ setting to match that ideal frequency response.
HD650 - The interesting thing about the HD650 is that even though it isn't the kind of headphone that really makes you cream your pants at how amazing it is, it's also one of the few that has stood the test of time and is quite neutral in general (other than the slight hump in the upper/mid bass that makes the HD650 a bit punchier, or the somewhat anemic sub-bass presence). I actually don't EQ the HD650 normally since I barely ever use it, and the only reason I would ever EQ it is if it became the only headphone I own--in that case, I'd boost the sub-bass region like this:
That low shelf boost isn't really a surgical one, but since the drivers of the HD650 doesn't seem to respond to surgical EQ'ing in the bass region too well, I find a more general one with wider bandwidth works better. This boost gives the HD650 more gravity in the sub-bass, since it's missing that quality compared to headphones like the LCD-2, 007mkII, M50, D7000...etc. I wouldn't EQ the upper/mid bass hump to be flatter since I enjoy the more visceral punch in the bass it has.
The reason I don't EQ the HD650 normally is because I mainly use it to check the mids on my mixes. I don't use it for leisurely listening anymore since I prefer the LCD-2 for that. The HD650's mids are some of the most neutral sounding of all my headphones.
M50 - UPDATED January 05, 2014
Here's the updated and more accurate/detailed ATH-M50 curve. This setting tames the boomy bass of the M50, as well as that etched/metallic treble, while fills a narrow notch in the upper-mids. The M50 sounds much more accurate/neutral with this EQ curve.
20 KHz, 10 dB, 0.35 oct
8700 Hz, -12 dB, 0.30 oct
5700 Hz, 12 dB, 0.42 oct
4036 Hz, -3 dB, 0.25 oct
3400 Hz, 4 dB, 0.33 oct
2000 Hz, -2.4 dB, 0.42 oct
300 Hz, 4 dB, 0.47 oct
130 Hz, -3.2 dB, 0.35 oct
95 Hz, 4.8 dB, 0.25 oct
40 Hz, -5.0 dB, 1.82 oct
If that sounds a bit bright for some of you (if you prefer slightly warmer than neutral), use this one instead (it's a bit more relaxed in the presence region):
Everything is the same except these two bands:
8700 Hz, -8 dB, 0.30 oct
5700, 8 dB, 0.42 oct
Stax 007mk2 - The 007mk2 shares a similar sonic signature to the LCD-2 in some ways, but isn't as "creamy" or overall weighty as the LCD-2. It's recess in the mids is similar to the LCD-2, and this curve fills it out nicely. (Updated 2011-11-27):
The 007mk2's treble is also a bit etched, so this curve also takes that etched treble down a notch so it sounds more natural. The sub-bass of the 007mk2 is quite good, but I think the very lowest of the lows can be more prominent (I don't bother going down to 20Hz since it's not really audible anyway), so for movies and games the low vibrations and rumbles are just a tad more visceral. The 007mk2's upper bass is a bit more prominent than neutral (similar to that slight bass hump in the HD650, but over a narrower range instead of a gentle hump) for that punchier bass.
And finally, my headphone audio chain is completed with Isone Pro (now called TB Isone). I never listen to music on the headphone without it. Excellent plugin that turns your headphones into speakers in an acoustically ideal room. Very realistic and with a very reasonable price tag. Better than any simple crossfeed, since it's far more sophisticated in its implementation of HRTF (Head Related Transfer Functions), which is what makes it sound so realistic (far, far more realistic than any crossfeed). If you want a simple crossfeed, you can try Redline Monitor, but it costs a lot more than Isone Pro and does far less.
Edited by Lunatique - 1/5/14 at 10:49am