Is Siri’s Absence on the iPhone 4 Due to Lack of Noise Reduction Circuitry?


When the iPhone 4S debuted with Siri, many iPhone 4 owners pondered why they weren’t able to have access to the voice recognition technology. Sure, there are unofficial ways to acquire Siri on your iPhone 4, but what is the real reason behind its absence?

CNET reports the main reason the iPhone 4 was left out was due to the absence of a particular “EarSmart” noise reduction technology in the A4 chip that powers the device, whereas the larger A5 processor does, as revealed in tear downs by iFixit. The company behind this technology is called Audience, and their recent IPO revealed a partnership with Apple:

The details answered a question that Linley Group analyst Linley Gwennap had about the A5 chip that powers the iPhone 4S: why is it so big? Larger processors are more expensive and can consume more power, and chip designers strive to trim every last square millimeter from their designs.

“Even after accounting for the dual Cortex-A9 CPUs and the large GPU that provides the A5 with industry-leading 3D graphics performance, the remaining die area seems too large for the usual mundane housekeeping logic,” Gwennap said in a report yesterday. “To reduce system cost and eliminate the extra package required for the Audience chip, Apple cut a deal to integrate the noise-reduction technology directly into its A5 processor, which appears in the iPhone 4S.”

Audience describes their earSmart technology as:

earSmart™ is an intelligent voice processor that delivers a clear voice and audio experience for mobile devices, allowing you to hear and be heard™ even in noisy settings. Our earSmart Advanced Voice processors use the science of human hearing to distinguish sounds, instinctively enhance voice quality and suppress surrounding noise, for radically clear conversations just about anywhere.

Below is a promotional video by Audience for their earSmart technology, which is also used in over 50 smartphones by numerous companies:

Essentially, the argument is that ‘EarSmart’ technology allows Siri to perform significantly better in noisy environments, and being built into the A5 chip means it’s only available for the iPhone 4S, instead of the iPhone 4. The technology works quite well, as Siri is still effective in relatively noisy situations, based on our tests over the past few months.

What do you think? Is this the reason why Siri is exclusive to the iPhone 4S? Are the dual microphones on the iPhone 4 not good enough for Siri?


  • Anonymous

    They should give it to iPad 2 users then.

  • Anonymous

    Why are people inventing excuses for Apple for what is purely a business decision?

    There is very little technical obstacle for Siri to work well in iPhone 4 or even 3GS, as previously demonstrated.

    The reason for Apple to keep  it a 4S exclusive is simple – to give users an incentive to upgrade their phones, and to avoid overloading the Siri server during launch of this beta function.

  • Edge

    Um no.  Siri works reasonably well on the iPhone 4 and other older devices.  The reason they didn’t include it was 100% purely for sales, to make the 4S more valuable.  It worked.

    One might say, well, if it doesn’t work perfectly, then Apple won’t let it happen.  There’s a truth to that but it falls flat because newer OS’s like 4.xx don’t work extremely well on the iPhone 3G, and yet Apple still provided it…

  • Chrome262

    Noise cancelation is about the same in both my 4s and 4. Both have issues in noise environments so I don’t see the benefit of the new chip.

  • Kraken

    Right… noise reduction.  Yet the iPad 2 which also has the A5 chip doesn’t have Siri.

  • Rio

    Sales sales sales, apples is all about sales! Siri however I don’t think is about sales.

    Siri is still in ‘beta’, Apple is still heavily working on it. Would they rather have all 4s access Siri servers or multiply that 30 something million by 4 and have iPads n other iPhones to use Sori aswell?

    Not to mention, apple will only release Siri on the 4 if it is flawless

  • Me

    Hogwash EVI works well on my iphone4 and I saw Siri working well on hacked iPhones. I predict Siri will be made available to all iOS phones when iphone5 comes out with significant additional features -unlike the 4s that has minimal additional features

  • Dale

    I don’t consider SIRI working in Canada yet, until the location services work.  As far as I am concerned SIRI is useless in Canada.  Originally we were to get location services around Christmas on the 4S, but so far nothing.

  • Anonymous

     Meh. Siri is still in Beta and my experience in watching friends cope
    with it on their 4s is tragic – if not funny. If its responses are based
    on its filtering ability thru EarSmart, then Apple (and its users) got
    conned. Needs work