Hello everyone. I am out of my mind to be thinking about getting into headphone testing. But the itch exists and I am reminded of it often in private communication with people asking me why I am not testing headphones.
I had tabled the whole thing for many reasons, most of which is that I am not happy with state of the measurement systems out there for headphones.
There has been a development which may make the measurement situation better. It is the Brüel & Kjær 5128 HATS (head and torso simulator). Here are a couple of quick promotional video on it:
I like the flexibility of the artificial ear/pinna and better reliability and repeatability that this brings.
There are some big negatives however:
1. The 5128 extends the simulation limit of the older "711" standard substantially. But with it, it also makes the measurements non-standard so existing research may be difficult to apply to it.
2. The cost. Man, oh the cost. The full HATS has a retail cost of $41,000! There is a truncated one that is a bit cheaper (just the head and no torso). This is a stunning amount of money to spend to measure headphones.
I have asked BK to give me an evaluation unit to test. After all, I still don't know if this is a good solution or not. They have been kind enough to say Yes and the unit will arrive soon. I only have a few short days when I get it to test and then return it. Let me know what you think I should be measuring/doing with it.
Whatever you all do, don't mention a word about this to my wife! I honestly don't know how to go and tell her I want to spend $5,000 on this let alone nearly 10X that!
Anyway, any and all feedback is welcome including whether we should even bother doing this.
Hi,
Being a headphone enthusiast I would applaud such an endeavor and looking forward to such measurements, not only to be able to apply a custom curve according to your measurements, but also to compare to other measurements found on the net. Oratory being one of my favorites however not all of his EQ presets work evenly good to my ears. But then, an EQ preset can only be a guideline from what you work with and adjust to your own preferences. No two ears hears the same. Solderdude’s measurements are equally good because on some occasions it reveales run to run manufacturing variations (see below).
A few concerns I like to raise.
The headphones measured :
1 : is the headphone provided by manufacturer;
2 : is the headphone provided by members, is the headphone one you purchased yourself or one of your collection;
3 : stock earpads, revised earpads (Sennheiser hd 580, 600, 650 come to mind as used in the latest hd 660s and being different to the older HD 580, 600 and 650 and now only available for the older models), new earpads, medium used earpads, old earpads, custom earpads?
First question :
A headphone provided by manufacturer, wouldn’t that be a golden sample measuring in line with what the manufacturer measured on their equipment, a sample within manufacturing variations? This would also imply the stock earpads are provided. This would not translate to the version I have (see below).
Second question :
To be able to provide an accurate EQ setting one has to rely on the measurements provided by the manufacturer compared to your own measurements, deviations need to be minimal. You need to be sure stock earpads are still present and used for measuring and take into account if they are stock, new, medium used, old or custom designed earpads. Logical conclusion would be new stock earpads, can you confirm this beforehand? That still leaves us with the questions on old or medium used earpads.
Third question :
Are the earpads new, medium used or old, research and measurement found on line show there are measurable differences between old, new and stock earpads, custom earpads measure completely different to stock old, medium used and new earpads. And then I haven’t even mentioned the width of someone’s head translating into the pressure a headphone puts on the head also resulting to a different measurement compared to your measurement rig. The position of the headphone on your head, the measurement parameters of your head.
I understand it all comes to averages, but when is an average no longer an average (read below).
All three question have two common nominations :
- What are acceptable variations?
- Are run to run variations taken into account, or is that even possible?
To illustrate :
- One of my first high end headphones purchased is/was the Sennheiser HD 650. On first impression ….. NOT IMPRESSED. Lack of lower extension, muddy lows and a severe lack of high extension. Never impressed me. Not one of the EQ setting I found on line, not even Oratory’s could bring satisfying listening experience, not even my own experiments. Until a member on this form noticed his HD 650 had a dented driver. Just out of curiosity I checked mine, and behold, the right driver of my headphone also had an inverted dent. After contacting Solderdude he agreed to measure my HD 650 with and without dent and without guarantees trying to rectify the fault/dented driver. Solderdude was able to rectify the fabrication error/fault and in the fowwoling measurements it came to light that I had a version that measured quite different to other/standard models he measured. Lows started to drop of earlier, highs had about 3/4 dB less than the standard models he measured in the past. Again, thanks Solderdude. With his findings I could apply some custom PEQ settings on top of Oratory’s settings which in turn made the Senn HD 650 a very enjoyable headphone to listen to. Hence my earlier statements somewhere in a tread on this form I liked the Drop HD 58X more than the HD 650. His findings and measurements, scroll to bottom.
- The Philips X2 HR. I liked the sound signature, however something wasn’t sounding completely right. Again to the rescue Solderdude. Turns out my unit had severe channel imbalance. His measurement were the key to properly eq them on top of the Oratory’s measurements and PEQ measurements.
- The Hifiman HE560, apparently there is the original version (first version), but also 2 silent revisions. How to know what version you have? What measurement to rely on? How to apply PEQ? (what sounds best could be an argument, on the other hand I like to EQ according to an EQ conforming to the model measured with version statement and then start to adjust to my liking)
- The Audeze EL8 (open or closed) also two silent revisions, same questions.
These four examples (and I’m sure I can come up with more) illustrate the run to run variations so returning to question 1 and 2.
Have you pondered on those?
In the event you will go forward, buy the equipment and start measuring could you please give some insight as to how you will implement and go forward?
Again, I’m all pro for your endeavor, still, some questions and practical applications and usefulness stay open. Meaning, a measurement without PEQ is useless (for me) taking into account you measured a sample within manufactured variations. A 10 band graphic EQ is acceptable. A convolution sample would be ideal if mirrored to the Harman curve (I like the most, also for the graphic and PEQ settings). The Harmon curve sounds the most natural to MY EARS.
I must confess that I just briefly read the speaker measurement and don’t follow any discussion or comments, mostly because what you measured so far is hardly available in Europe…. And to most extend, I seldom listen to speakers living next to a student dormitory trying to respect their time to study. Any speaker listening is only in the weekends (and I take into account if students are present during weekends to study time prior to/or during their exams) and on vacation time.
Don’t consider these comments to be critical to what you intent is or the rig you want to buy, just some questions that come to mind. I’m 100% sure the rig you have in mind will measure accurate, biggest question is how will it compare/translate to listening experience of the average listener?
Patrick.