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Does Bluetooth Really Work For Wireless Speakers?

I’ve been researching wireless ways to stream music from my digital devices to my computer audio playback system.  My present stock of devices includes iPad (third generation) and MacBook Pro, both running their latest operating systems.  When iOS and OS X systems work out, I have faith the rest, running Android or Windows, will fall in place.

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Wires are clutter.  They tie things down. Wires are frequently points of failure. Wires are a necessary evil.  Good wires are expensive but bad ones wreck your music. Wires exist by virtue of a reluctant acceptance that lurks, awaiting a better way.  Wireless data distribution is universally appealing.  However, until we achieve that workable better way, wires seem the best music signal path available. 

There are two candidate wireless audio technologies close at hand.  Which could be the solution of choice?  The best would simultaneously optimize performance, usability, market acceptance, reliability and cost.  Solutions that focus on profitability to the exclusion of listeners’ wants will be short-lived because information technologies innovate at a blistering pace and eventually, technology evolves to serve those who finance it – the customers.  Most listeners want great-sounding music. Many listeners want their music perfect.  All else fades.

At first glance, Bluetooth (BT) would seem the perfect candidate for the radio leg in the digital audio signal path. The attraction of BT is widespread implementation.  It has become a de facto standard.  BT technology has the native bandwidth to handle all presently accepted levels of audio quality.  Ten meters is a workable enough (though short) range for many situations where wireless audio would operate.  Another attraction of Bluetooth – it doesn’t compete with a limited-bandwidth Wi-Fi connection that may already be working hard to stream your music from the web.

However, Bluetooth is doomed to only satisfy part of the market.  It will most likely remain forever mid-fi, at best. Without significant innovation, any music that passes through a BT leg on its way to speakers is down-sampled to “true CD quality.”  The issue is -- the market-dominant implementation uses the A2DP protocol (a defined communication process) through the SBC codec (coding and decoding software.)  This arrangement makes BT inherently lossy.  Most of the musical data (96%) is lopped off for the sake of mobile phones.

The SBC codec was essential in the early days of BT when the infant technology was challenged to work at all.  SBC reduced processing overload and excessive power drain in so mobile phones had a chance.  Unfortunately, by the time the phones became more robust due to technology advances, SBC lossiness had become entrenched in the mobile industry.  Today, BT stands for lossy playback. *

Consequently, BT eliminates any audio quality above 16-bit depth and 44.1 KHz – often noted 16/44.1.  This “true CD quality” does “sound nice.” It’s considered within HD range but it’s not the best audiophile grade.  Audiophiles want lossless formats with 24-bit depth and data rates up to 192 KHz (24/192.)  This is studio master quality.  Music encoded at 24-bit depth contains 256 times more data than 16 bit, to support extreme realism -- the real truth in recorded music.  Audiophiles live for this.

“True CD quality” level does not disappoint the consuming majority of listeners but audiophiles want the best.  An operational definition of mid-fi can be “good for the greater crowd but not enough for truly demanding listeners.”  For present purposes, let’s say audiophiles are “the more discerning listeners who prefer to hear all audio nuances advanced technologies can reveal.”  Everything else is low-fi.

Search Amazon.com for “Bluetooth audio receiver” and you’ll find a host of speaker adapters and dock converter devices.  This is the low to mid-fi mainstream.  For a shining mid-fi Bluetooth example, here’s a review of the “Dynaudio Xeo 3 Wireless Loudspeaker System.”  Count the times the reviewer uses the term “smooth” describing this bundled system because he can’t honestly wax poetic with typical audiophile jargon.  And what about all that signal processing these speakers have going on?  Why do they need that?  The less processing the better.  Touting more processing appears to be marketing a problem as a feature.  This is wireless speakers but at what cost?

The other obvious wireless choice would be good old workhorse Wi-Fi.  Everyone whose home and office are wired these days have Wi-Fi networks.  Wi-Fi is the ubiquitous fixed lossless wireless networking solution.  As opposed to BT, the all-present lossy mobile wireless solution.  What we really need for playback is wireless that works for everyone, everywhere.

I have my eye on a system that uses proven, widely accepted, lossless Wi-Fi-like technology in a clever, re-invented way that avoids processing loads on existing home Wi-Fi networks.  More on that in my next post here on iHi-Fi.com.

Notes:

*  Back in 2007, Tim Gideon reported in PC Magazine -- a company called OINA developed a lossless codec for BT called SOUNDabout. Qualcomm, who focuses on making cellular microelectronics, bought up OINA and despite the scattered press mentions of a new standard since then, SOUNDabout has not heard from since outside of Qualcomm-based Android phones. Such is the way of the world.