Along with RF performance<Need to add link>, one of the biggest differences between cell phone models is their audio quality. Unlike RF however, audio is much harder to quantify. For starters, there is absolutely no industry-accepted standard for how a cell phone should sound, and few in the industry seem to take it very seriously. Some companies seem to have a total disregard for how their phones actually sound, while others seem to try very hard to produce phones that have excellent aural properties.

Audio quality can actually be broken down into two very distinct facets. The first is the phone's ability to reproduce the audio without adding distortion or unwanted noise. The second is the tonal balance of the resulting audio. Note that a phone's ability to reproduce a true rendition of the audio will vary from technology to technology, simply because GSM, CDMA, IS-136, and iDEN use different CODECs. A CODEC in the cell phone world is always a compromise between quality, and sending audio using the fewest possible bits. It is rarely possible to compare phones that use different technologies, but we can compare phones that use the same technology (GSM vs GSM, CDMA vs CDMA, etc).

Tonal balance is probably the most subjective of all, since different people have different ideas about what constitutes good tonal balance. My opinions on this matter are just as subjective as the next guy's, but I do pride myself on being an audiophile, so I do believe that I have a fairly good handle of what's balanced and what's not. However, that doesn't mean that my opinion is necessary in keeping with what you personally want from a phone.

When reading my reviews, your best best is to use my tonal balance comments as a guideline, and compare them to what I've said about other phones (some of which you may already be familiar with). As for the phone's ability to reproduce the audio however, that's much less subjective, and I do believe that my ability to detect distortion and other unwanted audio maladies is reasonably well honed. Once a flaw is recognized, the problem isn't whether it exists, but to what extent it really matters. This will depend upon your own personal threshold of tolerance when it comes to such matters.

Much of what we accept as good audio quality from a phone is merely relative to what we were used to before. For example, when I first switched from the analog world to the digital world, I bought a Nokia 2190 on Fido. I thought that phone sounded incredibly good, since it was better than what I'd been accustomed to up to that point. I still have that 2190 sitting around, and sometimes I charge the battery and pop my SIM into it just to hear what it sounds like. If I were rating that phone today I would probably give it such low marks for audio reproduction that I'd be recommending that no one wasted their money on it.

So even on less subjective matters as audio reproduction, background noise, etc, it still comes down to your own personal likes and dislikes. As with tonal balance, it is best to read my comments simply as a guideline. If you're one of those people to whom all phones sound just fine, then consider yourself fortunate that audio quality isn't an issue you have to be concerned with when you buy a phone. If audio quality is an important issue to you, then I can only hope that my comments help you to make the right decision for you.

When it comes to testing audio quality of a phone, I try to subject the model to as many different types of voice as possible. For example, some phones might sound great on female voices, but muddy on male voices. I phone a variety of pre-recorded messages, and I carry on two-way conversations. As for outgoing audio, I do ask callers to give me their opinion of the sound, but I don't rely on that. Instead, I call my voicemail using the test phone and I compare the overall quality against a reference phone (such as my Motorola P280).

Outgoing audio tests are carried out under a variety of background conditions, ranging from quiet rooms, to noisy shopping malls, to noisy vehicles. I do this to see how well the phone in question copes with the background noises, and how clearly the user's voice is reproduced in each situation. Many CDMA phones for example are horrendous when background noises are quite loud, but they sound great in quiet environments.

Audio Glossary