–Mike Giffin
In our last post, we took up the subject of lossless coding and how it enables wireless systems to deliver the same audio fidelity as wired systems. Ultimately, however, playback fidelity is determined by the quality of the digital audio file transmitted from the source device and the amplifier and speaker that convert that digital file into sound, which is what wireless audio is all about. We will reserve the discussion about different types of digital audio files when we announce a collaborative effort–currently in the planning stages–with a new website dedicated to the exciting new field of HI-RES Audio. For now, let’s cover the single most important factor determining the fidelity of your wireless audio experience: the amplifiers and speakers used for playback.
No matter how good the source, and even with lossless transmission, fidelity will still be compromised by a low-fidelity playback device. In fact, the quality of the amplifier and speaker is the single biggest factor in determining the sound quality of a wireless speaker system. Because many different wireless speakers use similar “upstream” technology, it is the sound quality of their amplifiers and speakers that differentiates one wireless audio system from another. In that respect, wireless speakers are no different from wired speakers.
For best fidelity, the amplifier in a wireless speaker must provide sufficient power to attain the volume levels you want. Clearly, a speaker used only for background music can use a low-power amplifier while one used for loud parties demands more power. Most people use wireless speakers for both background music and parties, depending upon mood and situation. Almost everyone wants to “crank it up” from time-to-time. If that describes you, make certain that you choose a speaker that can play as loud as you may occasionally want without breakup or distortion. Otherwise you’re setting yourself up for disappointment when you’re entertaining friends and want to get into some music. Moreover, it’s easy to damage an underpowered speaker if you try to drive it beyond its limit.
Check the frequency response of the speakers; in particular, you’ll find that only the best systems can provide satisfactory bass response. Because most people prefer small, single chassis wireless speakers, extracting bass you can feel (deep, realistic bass rather than loud upper bass) requires top-quality drivers, expert use of DSP (digital sound processing) and carefully designed bass reflex or passive radiator systems to augment the bass output. Finally, consider the sound quality of the speakers themselves; tonal accuracy and clean, transparent sound only come from the best speakers. If you’re looking for a small, single-chassis wireless speaker, make certain it is a stereo (i.e., two-channel) design with high-performance tweeters spaced as widely apart as possible so it can create a stereo image, or the audio “illusion” of music coming from a sound stage bigger than the speaker itself. ”Boxy” sound gets tiresome after an hour or so of listening.
Can a wireless system provide audiophile sound quality? Absolutely. With lossless coding, the transmission link maintains the exact fidelity of a wired system. In the end, getting high fidelity from a wireless audio system is the same as with any audio system; choose the system with the features you prefer, and make sure it has the best possible amplifier and speaker design.
Now that we’ve put any wireless audio fears to rest, there is one issue left to consider: with everything else in my life going wireless, should my audio system go wireless too? We’ll consider that question in the final installment in this series.
