Fresh into a new year and a new decade, worn out from trips to the 2020 Las Vegas International CES and the 2020 NAMM Show in Anaheim, California, I write this column filled with anticipation . . . and dread. Anticipation because I’m excited to see what new headphone innovations will appear this year and into the 2020s. Dread because I’m wondering how I’m going to test them.

Sure, there will be new models of traditional cabled headphones and earphones coming out for the foreseeable future, and evaluating and measuring those isn’t difficult after you’ve done a couple hundred. But the market trends I observed at recent tradeshows suggest those products will make up a decreasing percentage of what I review here at SoundStage! Solo.

Brent Butterworth

I got quite a jolt on my very first day at CES, when a JBL representative told me that true wireless earphones are projected to make up 50 percent of the company’s headphone/earphone sales this year. I wouldn’t have been too surprised to hear this from a Bose or a Beats, and yes, JBL is a mainstream brand available at any Best Buy. But still, JBL is a brand revered for decades by enthusiasts, and that still offers $10,000-plus speakers . . . yet even legendary JBL will be focusing on wireless earphones small enough to fit in a shot glass.

These products accept audio signals only through Bluetooth, so to measure them, you have to add a Bluetooth transmitter (which can introduce its own problems) and deal with the roughly 200ms latency found in most Bluetooth systems.

But evaluating them subjectively -- by simply listening to them -- is perhaps even more challenging. Not because they’re cheap or because of any limitations of their wireless technology, but because many of them are so sophisticated. And every one of them is, by definition, fed signals from a device (usually a smartphone or tablet) that incorporates powerful audio processing capabilities of its own, as well as an endless selection of apps that can alter the performance of the earphones.

Take the recently reviewed Soundcore Liberty 2 Pro earphones, for example. They work with an app that includes Soundcore’s HearID function, which tests your hearing and creates a response curve that optimizes the earphones to suit your ears. So the reviewer has to test the earphones on their own, with HearID activated, and also with the many other EQ curves provided in the app. And I’m not sure how to measure the efficacy of HearID, because how do I account for the characteristics of my G.R.A.S. Model 43AG ear/cheek simulator, which of course isn’t capable of taking a hearing test?


Measuring will become even more difficult as earphones with built-in, always-listening voice-command functions, such as the Amazon Echo Buds, proliferate. I worry that many of these products will, like smart speakers, be locked into certain services that can be accessed only through voice commands requesting certain “skills,” and I seriously doubt that a skill called “play 10Hz to 20kHz logarithmic chirp calibrated to 94dB SPL at 500Hz so you can measure my frequency response” will be available. I’m sure I’ll figure something out, but again, which of the growing number of EQ curves in these products do we evaluate?

You might counter that audiophiles don’t care about these technologies, but it appears to me that they’re rapidly embracing them. This month, I’ll be reviewing the new Drop + THX Panda headphones, which were built based on suggestions from the audiophile community on the Drop website. And what did the audiophiles want? It’s no surprise that they wanted planar-magnetic drivers -- but they also wanted Bluetooth. The headphones will launch with no EQ applied in the amplifier, but they have internal digital signal processing capabilities that will make EQ and other functions possible, and Drop is contemplating creating an app that’ll let you access these capabilities.

Do we evaluate these headphones and earphones based on their fundamental sound quality? Or on what their apps can do? How do we weigh one versus the other? Do we go back and see if similar processing might elevate modestly priced, relatively unsophisticated products such as the EarFun Free earphones to a new level of performance? How do we judge headphones and earphones when numerous methods of correcting their performance are waiting in every smartphone and tablet?

All of this adds up to increasingly complicated processes for reviewing -- and a much longer list of questions that headphone buyers will have to consider for themselves. I’m not entirely sure how we’ll confront all of these challenges, but I’d sure love to hear your suggestions.

. . . Brent Butterworth
This email address is being protected from spambots. You need JavaScript enabled to view it.

Say something here...
Log in with ( Sign Up ? )
or post as a guest
People in conversation:
Loading comment... The comment will be refreshed after 00:00.
  • This commment is unpublished.
    Mauro · 4 years ago
    Brent, have you considered adding a paragraph explaining how the headphone sounds like after EQing to Harman Curve.

    In the past, I thought it would have been useful for higher quality headphones that might have specific sonic features (low distortion, dynamics, detail retrieval), but in this article it seems that future is more complex and needs a common ground/reference.

    It happened to me when I bought the Audeze EL-8 open after your suggestion of the LCD-1. It is a wonderful headphone to equalize but how could I know it. No reviews cover this aspect. Tyll lately had been adding just a short suggestion for EQ but not a lot more..

    What do you think about it?

    PS: thanks for suggesting buying an Audeze headphone!
    • This commment is unpublished.
      Brent Butterworth · 4 years ago
      I've considered it, and I may do that in the future, but unless it's a budget model, I think it should sound good with no extra effort on the user's part. What EQ do you think I should use -- whatever's built into the phone/tablet? I should probably do a closer examination of those to gauge what their capabilities are.
      • This commment is unpublished.
        Mauro · 4 years ago
        That's a good point..I guess it might depend on the most common scenario for that specific headphone.
        But a generic approach, on the contrary, might work just fine and be very helpful to give the user a starting point. For example, using a free PC-based fixed-band (and parametric) like APO Equalizer might be very beneficial, so that everyone can experiment.

        On equalizing budget or expensive models, my opinion is that for both it would be limiting not to consider EQ when you can get a better sound for free.
        I see that you have doubts about EQing expensive headphones, my arguments just to share:
        - The owner of an expensive headphone - I suppose - is more likely to experiment with EQ for the sake of learning
        - Frequency response is not the only parameter that guides the purchase of expensive headphones, audiophiles seem to be all rage about "resolution" which I, personally, would attribute to dynamic and at the same time properly damped headphones, free of resonances; so they end up with a good foundation for EQ
        - Even if many manufacturers are moving toward a frequency response similar to Harman Curve, we are still in the process. Why not taking advantage of it, now?

        About myself to speak pragmatically, I am experimenting with APO Equalizer, Sound Blaster G6 built-in EQ and Audeze Cipher cable
        • This commment is unpublished.
          Brent Butterworth · 4 years ago
          I'm definitely considering it!

          "Resolution" merits a column all its own. As with "inner detail" and "microdynamics," it's a term that's so loosely defined and so subjective that I'm not sure it means anything. Take two identical headphones tuned for subjectively balanced response (i.e., Harman curve), tilt the treble in one up by 1 dB, and people will say the treblier one has better resolution -- even though it's not resolving any more or less.
          • This commment is unpublished.
            Mauro · 4 years ago
            That’s a very nice topic!! And you have the right amount of criticism to address it!

            I tend to find always an equivalent meaning with optics, being my field of work. A tonally accurate headphone is to me like an image with proper colors (not grayish, not saturated). Resolution is the ability to distinguish close features. In optics there is a proper definition based on the ability to distinguish two adjacent black lines, which I like to think that can be transposed into two close impulses in audio signals. In optics is strictly correlated with dynamic range/sensitivity and low noise. I like to think that in audio is the same.

            But who knows?
  • This commment is unpublished.
    Mauro · 4 years ago
    And what’s the life of a battery powered headphone?

    should be consider the active sound signature consumable?
    • This commment is unpublished.
      Brent Butterworth · 4 years ago
      I have yet to have a set last beyond their battery life, usually they succumb to some accident or get lost, but typically a couple of years for rechargeable battery life.

Latest Comments

@K MurrTidal!
@SteveTotally agree and I miss MQA very few tracks now available on Tidal. Even with ...
Like the article explained well, there will always be subjective notions to what we as ...
@Brent Butterworth"Too much bass" is too much bass if you think that the bass is too ...
How would you compare the sound stage between the T1 and T5?
You didn’t mention anything about time domain correction which is a big benefit of MQA. ...
Although I concur with most of the critique of the Kinki Studio THR-1 in your ...
Dustin 2 months ago Do You Need a Headphone Amp?
Amps make no difference in sound quality unless they alter the frequency response, which they ...
good drive 2 months ago KZ AZ09 True Wireless Adapters
had the same setup with these (t3 plus) and when i read your review i ...
thanks Brett for a very informative and well written review. I got the S3s and ...