Smartphone Audio Quality Testing
by Chris Heinonen on December 8, 2013 5:15 PM EST- Posted in
- Smartphones
- Audio
- Mobile
- Tablets
- Testing
Right now we have full data on four phones and partial data on a few more. We are working to compile as much data as possible to provide an overall look at the quality of audio from smartphones available today. The largest difference in current models is the power of the headphone output as some are much better equipped to drive more demanding headphones than others. As we compile data on more and more products we hope to see more differences arise.
We also have not seen much difference with different loads applied to the headphones. We will continue to test all three sets of headphones but the data here is for the Apple Earbuds. If different loads provide different results, then we will certainly report those different numbers in the future. It also appears that running Android phones in the automated routine causes the 20 kHz tone to be left out of the frequency response test. Humans usually can't hear this, I certainly can't, and so there isn't a huge amount of real-world ramification to this. It causes the reported THD+N to exclude that tone and provides a better result that phones that play it back. For the future, this will be done manually.
Here are the four phones we currently have, and more phones are being tested and reported on as quickly as possible to be added here.
Facebook
Twitter
RSS
188 Comments
View All Comments
Origin64 - Monday, December 9, 2013 - link
"Here we see that Beats is adding a +3.5 dB boost from 60 Hz to 90 Hz, but the deviation from 0 dB goes from 30Hz to 300 Hz. Past 6.5 kHz we also see a rise in the treble."And people pay 300 bucks for a headphone that does exactly, and only, this. Its a good joke, really.
willis936 - Monday, December 9, 2013 - link
To Chris:Check out NwAvGuy's blog if you haven't already. He appeared and disappeared a few years ago bringing with him a headphone amp design and (more importantly) a breath of fresh, objective air in testing audiophile headphone equipment. He has some good data there and comparing testing methodologies might be insightful for things to try here on anandtech.
cheinonen - Monday, December 9, 2013 - link
I've read his full blog and wish it was still updated.Impulses - Monday, December 9, 2013 - link
Tyll's Inner Fidelity blog is another great resource.adityanag - Monday, December 9, 2013 - link
This is excellent. Also the reason why I've been reading Anandtech since 1998. Keep up the great work, guys.Gadgety - Monday, December 9, 2013 - link
I appreciate this article, Chris. An improvement would be a summary table of all the models compared on one page, and some sort of analysis beyond the "poor performance" comparison. I've also seen data that the specs will change significantly for worse when headphones are attached to the phones.xodusgenesis - Monday, December 9, 2013 - link
Finally some in-depth audio anlysis. I've been waiting for this as I actually use my smartphone as a phone (I know shocker in today's age) and media player most of the time.ZoSo - Monday, December 9, 2013 - link
Would like to see some results of a few current WP8 phones, Nokia in particular.asgallant - Monday, December 9, 2013 - link
Awesome! I have been wanting to see some audio analysis done for a while now. Is there any chance of extending this to test audio on motherboards, sound cards, and laptops as well?lever_age - Monday, December 9, 2013 - link
Glad to see this. My suggestions are as follows:1. Include an output impedance measurement. If you're using these as decent-quality audio players with headphones, this is one of the most important things to know for certain headphones, at least. Who cares what the measured frequency response with a resistor is if your source's output impedance is causing +/- 5 dB swings in response for some balanced armature IEMs?
2. Standardize THD+N tests to a given output level for all phones (say 0.1 V or whatever else; the danger is picking something standard like 0 dBu that some phones could possibly not even reach). Don't just use whatever the max volume is, especially since that's into clipping territory for some phones. People don't scale their playback levels by how much power the electronics is capable of handling. I hope. Referencing a fixed level is more fair.
3. Please do keep reporting which phones run into clipping (and at what load) at volume settings at max or less. Also what some nonstandard settings like Beats Mode do.
4. Make careful distinction of THD with headphones as load and as not. If not loading with headphones-level impedance that is mostly testing the performance when hooked up to say a speaker system with a patch cable, which I don't think many people are doing these days.
5. When reporting maximum level, standardize to point of say 1% THD (or max volume, whichever comes first). Also note if headphones are used or not. It'd be meaningless to quote maximum levels far past the point of clipping.
6. If you have time, see if you can coax and measure some bad behavior out of the phone by using Wi-Fi, Bluetooth, LTE, etc. simultaneously, maybe some CPU/GPU load and seeing if that causes audio issues. Honestly, glitchy or cackling playback are far greater issues to audio quality than looking at 0.3 vs. 1 dB dips in frequency response at 19 kHz or something like that. Or output power levels most people don't need.