What it is
Peace EQ - the Test module for
the set of hearing capabilities + headphones
(https://sourceforge.net/projects/peace-equalizer-apo-extension/)
Easy to use — Hearing capabilities and Headphone agnostic — Based on science
I present you what I believe it is the most important software tool for listening to music: the Test module of the Peace EQ (Peter’s Equalizer APO Configuration Extension).
For now, only for those using Windows PCs as their music player.
Yes, I was part of the development and no, I’m not making any money when you donate to Peter.
I found this comparison to be really useful when thinking about this tool
Do you use viewing eyeglasses? Even if you don’t, they are so ubiquitous that if your vision wouldn’t be very good you wouldn’t think twice before getting some. Now you can do something similar about hearing too.
The two reasons for needing the calibration tool
Headphone tuning:
Any headphones you may own, regardless of the price, have been tuned in some way and that was a subjective choice of the manufacturer. This article is quite instructive: https://www.soundonsound.com/techniques/designing-measuring-reference-headphones
In summary:
There is no agreed standard for tuning headphones and their tuning varies greatly. Why do you think Grado sounds so different from, say, Sennheiser HD series? It is just tuning. For the most part the engineers are not that free during the process and the development funds are limited. The cost of the various things which go into the final product, the time taken, the competition, they all count for a lot and so there is no magic - if you ever believed in that.
The measurements are highly flawed and so they do not matter! They also vary in time, for instance with the aging of the earpads, and so on.
Hearing:
Your hearing is far from perfect. Your ears hear differently. But unlike with sight where it is very easy to know that you don’t see well, there is no easy way to know that your hearing may need some correction.
How you hear is a combination of your hearing capabilities and the way the headphones have been tuned.
The result can only be not good enough, there is no other way.
What was available until now?
I won’t explain here what an equalizer (EQ) is, I assume you know, perhaps you even played with some.
There are lots of equalizers out there. The vast majority of them recommend that you play with the sliders until it sounds good to you. That is OK if you want to play with it, as you’d play with a toy. But if you want to get as close as possible to the musical intention, then you have to know what you’re doing.
The professionals in the field are trained. You can go through that too if you care for it. And if you don't want to go through a proper school, then at least some tests will help. For the curious, here are a few, not only for the frequency response:
But they are not easy to use, they require work.
If you just want to understand the descriptors you may find in write ups about headphones, and speakers, then try this:
Thank you to Frans (Solderdude) for providing this graph. And read here:
https://diyaudioheaven.wordpress.com/tutorials/how-to-interpret-graphs/frequency-response/
There are also quite a few other software tools which appear to do something similar. I tried everything I could get my hands on and, to me, there is no comparison: the Peace test calibration tool easily wins. But I learned from the other tools and so I appreciate the developers’ efforts. Everybody has their own approach: some have proprietary algorithms, some say that they consider the headphone model you use, some ask you to identify the dip and troughs during a sine sweep, some have their software built into the headphones, some into the bluetooth chip, etc.
How the calibration Tool works
In short:
We chose a series of frequencies, with focus on the midrange where most of the musical information is, and play a pure tone for each frequency. With a slider that controls the volume, you choose where the hearing threshold for that frequency is, individually, for each of your ears. This way you are building the curve of your hearing abilities, individually for left and right ears.
Then we correct your hearing abilities by mapping them to the Equal Loudness contour curve: https://en.wikipedia.org/wiki/Equal-loudness_contour. If you can understand, read. If you can’t, this target is the best way we know of, scientifically, to estimate the human hearing sensitivity. These curves have even been standardised.
As you can see from the first graph in that Wikipedia article, the louder the listening level is, the less boost for the ends of the frequency spectrum (bass and treble) is needed. This is loudness: https://en.wikipedia.org/wiki/Loudness. Basically we humans are a lot more sensitive to the frequencies in the middle of the audio spectrum where, for example, our voices are, than to the ends of the spectrum and so we boosted the bass and the treble. This was a subjective decision and you can adjust them as you like.
The result?
I have had an interest in Hi-Fi for over 35 years and I have never had such a revelation, hence the strong statement I am going to repeat again: this is the best tool for listening music using a Windows PC as a source.
What headphones you own matters a lot less than you imagined.
What did I feel?
For the first time in my life I felt that It is all there, in the best balance I have ever heard.
English is not my first language and I used to blame this for the fact that I couldn’t understand the lyrics. Now I do, it is amazing!
No reason to raise the volume to accentuate what I couldn’t hear well enough.
Better stereo imaging since the ears hear in the correct balance.
I own a variety of headphones: Grado SR80 and 325e, Panasonic HD10 with my own merino earpads, Sony SA5000, Ora GQ (95% graphene driver, not just coated), my own headphones and I have about 10 different modern drivers in them: they all sound a lot more alike than I imagined possible, and all sound very good. Let me repeat: what headphones you own is a lot less important than you ever imagined.
While the differences between the drivers in terms of the frequency response are smaller than you thought, they are now more meaningful.
The rest of the tuning of any headphone (except the driver) does not matter!
The calibration tool takes into consideration everything else which is involved in listening: the earpads, the differences between your left and right ears, your age, the differences between the drivers for the left and right channels, no “matching to 0.5dB” needed (if you ever believed in it), everything.
Conclusion
As long as the drivers are decent (modern, with enough headroom - I’ll talk about all these in a future project), once you apply the calibration you’ll hear the best it is possible. More so, you may find that the question of which headphone you should upgrade to in order to get a significantly better sound becomes almost as meaningless as upgrading the amplifier.
Speaking of which: as I hope you are aware, the race for creating good and cheap electronics ended not long ago, in the last couple of years. You can now buy a DAC and a headphone amplifier with performance surpassing the hearing sensitivities for $100 each. Bookmark this: https://www.audiosciencereview.com/forum/index.php?reviews/, the only electronics review site worth reading, although once you buy what you need, you should be fine probably forever.
As for headphone reviews, stop reading them unless they are from people who, once this tool becomes popular, first calibrate the set of their hearing abilities and the headphones they want to review. It will be harder work for them, but a lot more meaningful to you. I stopped reading reviews many years ago. The last good ones, at a time when this tool did not exist, were here: https://diyaudioheaven.wordpress.com/, and you can see how much effort went into describing EQ related characteristics which, with this tool, should not be of any concern.
Donate to Peter Verbeek. He has put a significant amount of work over the last many months. If you decide to sell one or more of your headphones because there isn’t much difference between them after all, donate to Peter: he made that happen for you.
Do you expect anyone to give you, for free, a pair of eyeglasses custom made for you?
Again, I am not making a cent from the donations but I have never been so pleased with how my music sounds - I have been dreaming of this tool for years, thank you Peter! and I like the idea that you will enjoy it too.
Cheers,
Silvian