Measurements and subjective preference of cans

I am doing some research into objective and subjective evaluation of headphones. I am looking for some opinions from audio enthusiasts about headphones.

What are your favorite headphones?
What are your favorite types of headphones? (in-ear, on-ear,circumaural, supra-aural)
Do you believe that the current standards for objective measures are useful?
What should headphones sound like?
What makes a good headphone?

I am just looking for informal impressions and opinions as to how you feel about headphones and the audio reproduction through them.

Objective measures

I left the "Objective Measures" question open ended intentionally. The data on headphone metrics appears to be lacking IMO. I am primarily interested in other opinions regarding the metrics they have seen and used.

My search on headphone papers turned a series of different measurement techniques; HATS, GRAS, Head Acoustics Artificial Head Measurement System, and potentially utilizing a diffuse field EQ curve as well as ITU standards (ITU-R 468 noise weighting, ITU-R BS.708- Probe Mics).

What is not described is the analysis of the given metrics and how to interpete them into something meaningful. It is useful to quantify as many parameters as possible. But without correlation to specific attributes that relate to the subjective experience of the listener, these metrics become arbitrary or ambiguous.

Given that all metrics used in engineering are relative, I have yet to see a headphone measurement that was given with a defined transfer function as related to some other known and established metric that has been identified as describing objectively, essential attributes that pertain to audio fidelity.

Thanks so much for your input. I look forward to reading your feedback, experience, and opinions regarding these topics.

Please forgive any errors in etiquette due to my ignorance of using these forums.

Therein lies the problem. There are some accepted standards regarding a surround sound sound system, as to where to place your speakers. There are standards by which we use to measure a loudspeakers frequency response ( using free field microphones in an anechoic chamber) and a determination as o what that response should be shaped like in order to achieve what we consider "accurate" sound.

When talking about headphone reproduction we have no designated or defined response or transfer function that has been determined to be "accurate" in the reproduction of the original signal.

When many of the standards groups for ITU, IEC, CEDIA or AES gather they will often work on methods to use the accumulated knowledge and wisdom of many audio industry experts to create some sort of metric that can be utilized by the industry and consumers to give some feedback as to the level of performance that a particular product has.

I don't believe thus far, that the industry has come up with a protocol that really quantifies the accuracy or performance of headphones to date. I realize that there is much debate concerning which attributes are the most important when defining this metric. Although even the most basic measure of say a frequency response curve (what should the curve look like?) has yet to be determined.

Now, I understand of course that many have collected frequency response of many headphones using a head and torso system or the GRAS. But when you look at those measurements can you say, given two headphone measurements of two different headphones, which one is more accurate as far as timbre response?

This is why I am seeking input from those who have spent much time listening too and evaluating headphones such as yourself. I would greatly appreciate any thoughts regarding the measure and quality of current headphones and what you believe is the beth method of achieving that.

Thanks again

Timbre: The octave to octave balance of the sound spectrum as defined by its envelope; amplitude, frequency bandwidth, attack time and characteristics, decay, sustain, and release.

The term "flat" is often used when expressing a frequency response but is only meaningful when defined by parameters or context. "Flat" response will usually refer to an expression or measure of a free field response (no reflections).

I have often found that interpreting a measure is often more important than the measurement itself. When a measure is taken it must be correlated back to some other data that helps define that measure. Quantifying data back to a given known and then determining how we subjectively experience that particular attribute is how specific functions help us ascertain our universe.

A loudspeaker when measured in an anechoic chamber with a free field microphone will have a given response. It is considered that a relatively smooth or flat response is optimum. If you then take a measurement of this same loudspeaker in a room with the same free field microphone, you will have an entirely different response ( assuming same parameters for measurement, FFT gated, sweep or steady state). This is not any inaccuracies or linear distortion in the loudspeakers response, but merely the boundary affects of the room as you approach a diffuse field response. This transfer function is not an indicator that you have deviated from the original "flat" response. It is the natural physics of wave propagation in a defined space over time.

The timbre response of a given acoustic device is defined by it's acoustic environment. It will also help tell us how we will experience this acoustic event. Utilizing what we currently know about defining what makes a loudspeaker sound good and the way in which we physiologically interprete the sound coming out of the loudspeaker, it seems that a more useful metric for headphone frequency response could be created.

Thanks so much- I look forward to hearing more about your experience electrostatic ear-speakers and the most intriguing AKG K1000's.

This does look exciting.

I also have a pair of RS1's. Interesting, you show that you use these for portable use. Do you find them manageable, given their size for portable use?

I also agree about needing more research.

Thanks for the input.