Saturday, November 9, 2013

CanOpener for iOS

Most of us nowadays use an iPhone, iPod, or iPad to listen to music through headphones.  I recently found an app designed to enhance the sonic experience and offer some valuable listening information at the same time.  The app is “CanOpener” from Good Hertz LLC (I am in no way associated with the app or developers; I just think it’s a great app) and brings some unique features to the listener.

The first thing you see when you open the app is a list of headphones to choose from.  The list right now (Version 1.1) includes:
Apple EarPods
Apple Earbuds
Audio-Technica ATH-M50
Beats Pro
Beats Solo HD
Bose AE2
Bose QC15
Bowers & Wilkins P5
Etymotic hf5
Etymotic mc3
Etymotic mc5
Generic Earbuds
Generic Headphones
Generic In-Ears
Klipsch Image ONE
Sennheiser HD 280 PRO
Sennheiser HD 580
Sennheiser HD 598
Sennheiser HD 600
Sennheiser HD 650
Sennheiser HD 800
Shure SE215
Shure SE315
Shure SE425
Shure SE535
Shure SRH440
Shure SRH840
Shure SRH940
Sony MDR-7506

Choosing your headphones (or the closest match) allows the app to monitor what’s happening in your ears more accurately.  The app will play anything you have in your iOS Music app (if you have iTunes Match, it won’t stream from iCloud but will play anything that’s been downloaded to your device) and can also play FLAC files if they are transferred via iTunes.  Music sorting matches what you have in your Music app, including Playlists.  The only very minor bummer I’ve found is that playing files through CanOpener does not register in the iTunes “Play Count” metadata field, but I might be one of the only people in the world that keeps track of that kind of thing.

In my opinion, the app design is beautiful. Here’s what it looks like from launch to music selection:

The crazy spinny circle thing in the middle of the pixelated album artwork is time advance/rewind.  Unfortunately it won’t let you scratch your music like DJ Jazzy Jeff.  Can’t win ‘em all.

Once you have your song selected, you have a couple of options to modify your listening experience.  The first is “Crossfeed” and seems to be the biggest marketing draw to the app. Here’s how the developers explain it:
“CanOpener’s crossfeed algorithm allows your headphones to behave a bit more like speakers. The design, a result of extensive research and listening tests, incorporates several broad characteristics of an ideal loudspeaker setup, creating a more spacious, natural soundstage over headphones.”

I personally never much minded “headphone” sound, but I find myself really enjoying the crossfeed feature.  On a basic level, the app takes some Left and puts it in Right and vice versa, but does so while intelligently managing things like phase cancellation.  It noticeably changes how your music is presented via headphones.  The adjustable parameters are Amount (values from 0 to 150% in 25% increments) Angle (from 0 to 75 degrees in 15 degree increments) and L/R balance (a pan adjustment from 100% L to 100% R in 10 % increments).  Also available are toggle buttons for Mono, L/R Flip, and Polarity Reverse (making the app handy for system troubleshooting too!)

There’s a great visual presentation of what’s going on with crossfeed too.  I’ll run through the crossfeed presets so you can hear what’s going on in your ears. (I recommend headphones):

Normally, the question mark in the center of the screen is a neat silhouette of your chosen headphones to represent your place in the aural world.

The other way to modify your listening experience in the app is the Equalizer.  It is a very basic EQ, offering only Bass and Treble adjustment.  Bass frequencies range from 31.5Hz to 250Hz and can be gained up or down by 6dB in .5dB increments.  Treble offers the same gain adjustment from 2kHz to 16kHz.  I personally leave the EQ flat but enjoy the Spectrogram because it’s pretty.  I guess it also provides some information on the power levels of frequencies or something, but mainly it’s pretty.  And you can change the colors to match your outfit!

Here’s what it looks like:

My favorite feature in the app is the Dosimeter.  We all know that people listen to their music WAY too loudly, but there hasn’t really been a good way to know how too loudly.  As a sound designer, my ears are definitely within my top 5 favorite and valuable body parts and I want to keep them healthy and safe.  CanOpener has a great Dosimeter which they claim to be pretty accurate.  It’s one of the main reasons the app asks you to choose your listening device when you launch it.  It’s also realtime and cumulative to give you a current and lifetime dB SPL reading.  Unfortunately, the app is smarter than I am and knows I’m streaming and therefore won’t show me crap on the dosimeter so, to show you, I have to take a crappy screen video of it working.  Also, I just installed the app on my iPad so I could take said crappy video with my phone, which is why the lifetime counter is basically nothing.

Here's what it looks like in action, with awful audio:

I really love having a gauge to know what I’m doing to my ears while I selfishly block out the rest of the world with my headphones.  Disclaimer: the dosimeter is accurate, but only for the headphones on the list.  Here’s what the developer says: “For supported headphone models, CanOpener can measure precisely how loud you are listening, helping you monitor your listening habits and protect your hearing.”  Luckily, I have Bowers & Wilkins P5 headphones (looooooooove them) and therefore can get a good number.

I have been using the app much more than I anticipated when I purchased it.  I really enjoy the crossfeed and dosimeter… enough to write this.  At the very least, it’s a great audio app to have on your device for three bucks.

The app is available only for iOS and costs $2.99.  Developer website:


  1. This comment has been removed by the author.

  2. New headphone models for version 1.11 are:

    AKG K702
    Bowers & Wilkins C5
    Sennheiser HD 25-1 II
    Sennheiser Momentum