by Todd Whitesel
This audiophile glossary will help you get familiar with some commonly encountered terms:
180-gram vinyl: also known as “heavy vinyl.” Most LPs are pressed on vinyl weighing around 120 grams. The current practice with many vinyl reissues is to use 180-gram vinyl, which is less prone to turntable resonations and, when recorded properly, results in a quieter overall presentation.
Red Book CD: the industry-standard compact disc: a two-channel recording with a 16-bit depth rate and a 44.1 kHz sampling rate.
Bit depth: the number of bits available to capture audio. Red Book CDs contain 16-bit audio. Bit depth determines dynamic range.
Sample rate: The number of times audio is measured (sampled) per second. Red Book CDs have sample rates of 44.1 kHz or 44,100 slices every second. Sample rates determine the highest frequencies that can be reproduced.
High-resolution audio: Many high-resolution recordings and downloads contain more information than Red Book CDs, and may have bit depths of 20 to 24 bits and sample rates from 44.1 kHz to 48, 88.2, 96, 176.4, all the way up to 192 kHz. DVD-quality audio is typically recorded at 24 bits with sample rates of 88.2 kHz or higher. The resulting files are too large to fit on a standard CD. Many computer media players (Media Monkey, Foobar, Windows Media Player, Play and VLC) can play audio files at sample rates up to 96 kHz with a compatible sound card.
SACD (Super Audio CD): a dual-layer CD whose audio data is encoded with a process called Direct Stream Digital (DSD) at a sample rate of 2822.4 kHz. Most SACD releases are hybrids, containing a standard Red Book layer (readable by all CD players) and a SACD layer, which can be read only by compatible players.
HDCD (High Definition Compatible Digital): This Microsoft-owned technology, in theory, boosts the sound quality of standard Redbook CDs, using processes to encode the equivalent of 20 to 24 bits of data in a 16-bit digital audio signal. HDCD CDs can be played in any CD player. However, some manufacturers offer CD players with HDCD decoding, which responds to the signal. Otherwise, the disc will play as a normal CD.
FLAC (Free Lossless Audio Codec): a file format that compresses digital audio files with no loss of information. FLAC is what is known as a “lossless” format and is one of the best ways to backup CDs and save hard-drive space without any loss of fidelity. FLAC files can easily be burned back to CD, and as the name indicates, it’s a free open-source format, not owned by anyone. FLAC also plays gapless audio, a big plus when listening to or burning albums whose tracks segue into the next, such as Pink Floyd’s Dark Side Of The Moon.
MP3: a file format that can compress digital audio files to 1/10 of their normal size. The tradeoff is a loss of information. MP3s, thus, are known as “lossy” files.
by Todd Whitesel