iPhone 4 noise cancellation chip demoed with comparison video

Last summer, when the folks at iFixit first did a tear down of the iPhone 4, one of the interesting tidbits they revealed was that the iPhone 4 has two mics (which is more than most other cell phones), and that it has a white-labelled (manufacturers details removed upon request from Apple) noise cancellation chip in it. The idea being that ambient noise is identified by the second mic, and processed and cancelled out by the chip -- leaving the person listening to whoever is speaking into the iPhone 4 with much clearer audio.

Furthermore, a few months ago, you may have noticed that iFixit -- along side the help of Chipworks -- revealed the unbranded chip to be a low power audio signal processor manufactured by Audience. The same noise cancellation chip found in the Google Nexus One phone.

While that in itself may not be all that interesting, we thought you may be interested in the YouTube video iFixit sourced to demonstrate the power of the Audience chip. The video below is a recording of two separate voice mail messages called from the same noisy location, but on two different phones. One is from an unnamed, standard cell phone, the other is from the iPhone 4.

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Source: http://www.ifixit.com/blog/blog/2011/05/17/unveiled-audience…

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Last summer, when the folks at iFixit first did a tear down of the iPhone 4, one of the interesting tidbits they revealed was that the...

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nicleT

Wow, very impressive.

BTW, TUAW please ban these spammers with the same "I just paid $22.87 for an iPad2... bla bla bla" comment. I know they change user name every time but the message still the same. It pollute our post environment, it's very irritating.

July 30 2011 at 12:29 PM Report abuse Permalink rate up rate down Reply

Oshawapilot

It's pretty limited beyond a certain noise level. I work in an environment where there's constant background noise and people I try to call constantly tell me that the noise is drowning me out.

A busy office, perhaps it works.....extremely noisy industrial environments, not so much.

July 30 2011 at 10:28 AM Report abuse Permalink rate up rate down Reply

Swami

I sometimes work in sound engineering. The problem with noise cancellation is that it's hard to distinguish between the sounds you want and the ones you don't want. It's nearly impossible to remove unwanted parts from a signal without damaging the overall signal. Especially if the microphones are placed so close together. Even though the iPhone sounds clearer, it's harder to understand what the guy is saying. If you listen to the iPhone first, and then to the other phone, you'll notice a price is paid for noise reduction.

July 29 2011 at 8:15 PM Report abuse Permalink rate up rate down Reply

Shannon Doherty

Apple should've done a video/audio file like this on their iPhone 4 website to really have this feature hit home. I know other phones have it like the Nexus but such a demonstration links it directly to the iPhone and shows that its call quality has improved from the 3GS.

July 29 2011 at 6:39 PM Report abuse Permalink rate up rate down Reply

Rand Wilson

WOW - that IS amazing..

July 29 2011 at 4:07 PM Report abuse Permalink rate up rate down Reply

Michael Long

They need to use the second mic for automatic volume control as well. Be nice if the system could bump the volume when playing music or a book when you're on a subway or walking down a street.

July 29 2011 at 3:21 PM Report abuse Permalink rate up rate down Reply