It never fails. Write an article about noise-canceling headphones for a mainstream publication, as my colleague Geoff Morrison did for The New York Times, and you’ll hear from readers about a variety of “hacks” for doing noise-canceling with better fidelity and/or for less money and/or to eliminate the dreaded phenomenon of eardrum suck. The most common suggestion is to use earplugs in conjunction with standard passive headphones. Others suggest using high-quality earphones and putting noise-canceling (or passive) headphones over them.
Binaural recordings -- which use microphones placed inside simulated ears on a dummy head -- produce an uncannily realistic sense of space when heard through headphones. But because binaural recordings tend to sound only so-so when heard through speakers, most record labels and engineers don’t release them. For the last couple of years, Chesky Records has produced almost all of its recordings in the Binaural+ format, and I use them in all of my headphone reviews. So when I recently got a press release from Chesky touting Jazz, the latest release from bassist/singer Casey Abrams, recorded “using our new recording methodology which features a stereo ribbon microphone,” I worried that this golden era of binaural recording was over.
I got a surprising phone call a couple of weeks ago from a fellow audio writer working on an earphone review. He doesn’t review a lot of headphones or earphones, and didn’t know what to make of the latest review sample he’d received. “They have no bass at all. None. I don’t get it,” he said. I happen to have discussed this issue a few years ago with the manufacturer of these earphones, who told me, “I have a lot of customers who want that sound.” I’ve battled online with a few of them, who insist that headphones and earphones with elevated treble have more detail. I advised my colleague to write one of those “If this is the kind of thing you like, you’ll like this” reviews for which the old Stereo Review was notorious.
It’s clear that the listening habits of headphone enthusiasts are changing. Recently, HiFiMan launched the Ananda BT headphones -- a Bluetooth version of its Ananda planar-magnetic headphones -- which, at $1199 USD, are arguably the first true audiophile-grade Bluetooth headphones. Clearly, there must be some interest even among hardcore headphone enthusiasts for playing music -- or whatever -- from smartphones.
I get frustrated when people criticize the practice of audio measurement without having examined the issue in any depth -- but with headphones, I can forgive. The measurements for most audio products, such as speakers and amplifiers, are well established and easy to grasp. Even in high school, when I barely knew a capacitor from a choke, I could understand most of the measurements Julian Hirsch published in Stereo Review. But headphone measurements are nowhere near as intuitive -- a problem I hope to solve with this article.
Thanks to recent research, we now understand a lot about headphones. But there’s one part of the headphone puzzle that I haven’t understood at all, and until a few weeks ago, neither did anyone else I’d talked with. It’s a phenomenon I call “eardrum suck,” and it occurs with some noise-canceling headphones. When you put the headphones on and activate the noise-canceling function, it can cause a feeling like riding a high-speed elevator, where you’re whisked abruptly into a region of lower atmospheric pressure, and the higher-pressure air inside your ear pushes your eardrums out slightly. For many, including me, it’s an effect so uncomfortable it can cause us to leave our expensive noise-canceling headphones in a drawer, unused.