What Contributes to Audio Quality?

Audio quality has come a long way from the days of handheld transistor radios and mono tunes issuing from the AM dial. Today’s home and portable audio devices not only offer stereo and surround sound, but also employ digital technology to replicate original recordings exactly. Add to this the ability to carry an entire music library on a small chip, and we seem to have entered the perfect audio world.

However, there are still things we can do to tweak audio quality. For portable devices, it comes down to file type, as compression can degrade audio quality. For home theater systems, hardware makes the difference.

Portable audio quality: Audio files come in different formats, with larger files generally maintaining the highest audio quality. Wave files, for example, are a popular format for ripping compact disc (CD) music because they maintain the same audio quality as the original recording. Every variance in every note and every nuance and tone is preserved in a lengthy trail of bits. It is because wave files are so exacting that they are extremely large in size.

Compression schemes like MP3 make files smaller than the original so that they take up less memory. To do this, certain data bits from the source recording are deleted. The result is a copy with lower audio quality. Though MP3 files sound fine on portable players, if you play an MP3 file through a home stereo system and follow it with the original CD or wave file, you’ll likely hear the difference. Depth, fullness, percussion and other sounds are compromised through compression.

To help counter this effect, download music using the highest bit-rate available. For example, MP3 files sampled at 320 kilobits per second (kbps) have better audio quality than those sampled at 192 kbps. The files will also be larger, but still much smaller than their wave equivalents.

Home audio quality: In a home theater system, there are some obvious factors that go into audio quality. The components themselves and their interfaces can have a significant effect. Optical or digital audio interfaces are superior to older analog left/right cable connections.

Speakers vary widely, and expense isn't always an indicator of good audio quality. Buy to taste or ask someone with a good ear along to help you decide. Regardless of speaker type, speaker wire can make a bigger difference than many people imagine in audio quality. Oxygen-free, copper-braided speaker cables of the correct thickness or gauge will significantly improve audio quality over thin, low-quality speaker wire.

Thicker wire ensures frequencies will arrive at the speaker without degradation or loss. For the average person, 14-gauge copper braided speaker cable is probably sufficient. Audiophiles will likely prefer 12-gauge cable for surround sound speakers and 10-gauge speaker wire for subwoofers. Since lower resonances are lost more quickly than high frequencies, thicker wire helps retain more bass quality. Simply upgrading poor speaker wire on existing speakers can significantly improve audio quality.

Speaker placement also affects audio quality at home. The signals should converge in the defined area of the listener. If the “sweet spot” is towards the front or rear of the listener, some audio quality is lost to the ear, even though the speakers are delivering it to the room.

High-end receivers have a feature to adjust the delay in surround sound speakers so that the sound from each speaker reaches the sweet spot at the same time. Surround sound speakers placed improperly can create interference of sound waves, muddying audio quality. Furniture, rugs, walls and ceiling height will all effect audio quality by absorbing or bouncing sound waves.

Keeping these things in mind, getting the best audio quality from your home theater comes down to good components with digital interfaces, decent speakers with optimum placement, and good speaker wire. If you’d still like better audio quality - assuming the receiver already has digital interfaces and provides surround sound - you will probably benefit most from a speaker upgrade. However, check all cabling first to ensure nothing is loose or damaged, as this will interfere with audio quality.