As many of you may know, we’ve recently moved to the new B&K 5128 headphone measurement system. There are a number of reasons for this, which can be found in this video here, along with this FAQ here. Here’s an additional overview video:
Reference Curve Testing by the Community
This thread is a compilation of headphone measurements and EQ profiles for users to try out on the headphones they have with the purpose of providing feedback for how our reference target is perceived. We will eventually go through the results and combine them with our own internal testing to see what we do moving forward.
Our new reference curve has a strong theoretical foundation but we still need to test it on a wide range of users. While doing so in a forum setting like this lacks any and all controls required too make this even remotely scientific, we want to get feedback and input from users to indicate where we need to test further to see if additional adjustments should be made. Think of this more like a rough estimate for which direction to go rather than a clear indication.
For instructions on how to set up basic EQ, check out this video here.
For this particular test, make sure that you have pre-gain set to 0, and reduce digital volume on your player accordingly:
Reduce this in your player or other digital volume:
Each EQ profile also includes an adjustment filter a 3khz where you can increase or decrease the energy for ear gain level.
While we have comprehensive research on what people prefer for the distance between bass and treble and the overall ‘slope’ (Harman), this research is based on a two point preference adjustment, one for bass below 100hz and one for treble above 2.5khz. It does not specifically identify what people prefer at the strongest part of the ear gain at 3khz.
With that said, in the more recent version of the Harman research there is a built-in adjustment around 3khz, suggesting that this is a key element to listener preference worth investigating. Additionally, our recent interview with Dr. Sean Olive confirmed that this adjustment was made based on listener feedback.
Previous preference research does exist for this region (Gaetan Lorho target), which used just a single filter but didn’t include additional bass to treble adjustments. And, while this target isn’t commonly used, it’s yet another reason for looking into what people prefer for this region.
So, right now, we have a slope that’s a straight line that ‘tilts’ 8dB from bass to treble. BUT, what we don’t have is data on how people perceive this in practice, and whether or not it makes sense to have a variable slope to accommodate how people hear the strongest part of the ear gain at 3khz.
Here are some examples of research done on what kinds of slopes people prefer, you can see that for the most part the bass to treble delta is similar, however these slopes are also variable to some degree, with Harman being the strongest outlier when it comes to listener preference (perhaps due to anchoring bass adjustments to the subwoofer crossover).
The EQ profiles below are meant to get the headphones in question reasonably close to a straight slope reference curve. What we’re looking for is feedback on this slope, and IF you find the 3khz region in need of adjustment for your preferences, please indicate the level of adjustment you did in dB. If you prefer it without any adjustment, just indicate 0.
Copy and paste the following template to provide feedback using my example here:
- Listener age: 35
- Headphones: Sennheiser HD 600
- Source: Zahl HM-1
- Pad age: New
- Score before 3khz adjustment (1 is low, 5 is high): 4
- 3khz Filter: -3dB
- Score after 3khz adjustment: 5
- Notes: This sounds close to an even tonal balance across bass mids and treble with natural timbre reproduction for instruments and vocal tones. [If it sounds to warm, bright, strident, harsh, glaring, shrill etc. indicate that here, along with how it sounds before and after any 3khz adjustment]
Note that these aren’t perfect, and there is bound to be some variation depending on the unit, pad wear, or headphone coupling differences and related effects. If any of these profiles make things sound very wrong beyond merely preference adjustment, please indicate that as well.
ONE KEY THING! Despite the fact that after EQ the measured frequency response result will be similar for each of these headphones, that does not mean they will sound the same. It also does not mean that you’re necessarily hearing ‘the target’ - again because of variation across different heads, pads, units, etc. So if you have multiple headphones listed here, please try these out with each of them - that’s the best feedback we can get.
I’ll be adding more to this list as I create them, and for those wanting additional ways to read these filters, along with closer matched results, I’ll be putting those up soon as well.
HiFiMAN Edition XS
HiFiMAN HE-6 (with Sundara 2020 pads)
Sennheiser HD 560 S
After EQ (this unit had a slight channel imbalance so I averaged the channels for this)
Sennheiser HD 600
Sennheiser HD 800 S
Audeze LCD-X 2021
Sennheiser HD 650 / HD 6XX
One thing to note with this model is that depending on the positioning, there are bound to be two common and… related results. Basically one of them has a more prominent 5-6khz peak, while the other one has stronger upper treble. So I’ve made EQ profiles for both positions. If one doesn’t work for you, it might be worth trying the other one. So please indicate which is which in your feedback.
HD 650 frequency response in position A (more upper treble)
EQ Profile A
After EQ A
HD 650 frequency response in position B (5-6khz peak)
EQ Profile B
After EQ B
Adding Meze Audio Elite with leather pads:
You’ll have to add those additional filters at the end there - I ran out of room.
If you don’t see your headphones listed, please indicate which model you’d like to try and if we get enough requests we can make profiles for them - just keep in mind that we’re trying to keep it to accessible models for the moment before making them for the ultra high end stuff.