CD sales are rising and you need a really good CD player to hear them at their best
With a compact disc, you 100% own the album. So, no subscription is required, and no worries that your favourite artist might take issue with your streaming service, grab his 'Old Black' guitar, and ride off into the sunset, never to be heard of (by you) again.
Introduced in 1999, Super Audio CD (SACD) offers higher resolution, up to 30 minutes more play time than CD, and multi-channel mixes. It was portrayed as 'next-gen CD', but a format war didn't help matters – SACD went up against DVD-Audio as the next big thing – nor did the public's growing interest in music downloads. But SACD still has its fans, especially in the classical music genre, where sought-after second-hand discs can sell for eye-watering prices.
Released in 1995, High Definition Compatible Digital (HDCD) aimed to raise the CD performance bar by increasing CD's available dynamic range from 16 to 20-bits. HDCDs will play in any CD player, but the format struggled to make its mark with mainstream buyers, so the discs are pretty rare, and there is a limited choice of titles.
SACDs are backwards compatible so that any CD player can access the CD layer. But to hear the best from the format, you need a dedicated SACD player.
An MQA-CD is a regular CD encoded with Master Quality Authenticated (MQA) technology. MQA claims that its encoding process delivers studio-quality even when you play the disc on a regular CD player. You need an MQA-enabled CD player or a standard CD player plus an MQA-enabled DAC to hear the maximum quality.
CDs typically offer a sampling rate of 44.1kHz and a bit-depth of 16-bits. This 44.1 rate captures the upper limit of human hearing – the human ear hears up to 20kHz, max – and is in line with the Nyquist-Shannon theorem. This principle states that a digital sampling system must have a sample rate of at least double that of the highest audio frequency sampled to reproduce the audio perfectly. Bit depth refers to the amount of stored digital information, i.e. ones and zeros — 16-bit sampling stores up to 65,536 levels of information. Consequently, compact discs can sound very good. However, streaming services now regularly offer music at 192kHz/24-bit, beating CD's standard.
The compact disc is also more durable than vinyl and cassette tape, but it is not 100% resistant to damage, far from it. Do not, as a breakfast TV presenter did when CD launched in the 1980s, cover your CD in honey and coffee and expect it to work as usual.
CD recorders are a trusted solution for those looking to preserve music stored on (even) older formats, such as cassettes and vinyl. Many CD recorders feature analogue and digital inputs, letting you record from both analogue and digital sources – subject to the laws of the land! CD recorders can also, of course, play regular CDs. But not all CD players can play CD-R and CD-RW formats, so check before buying.
You can record just once to a CD-R (compact disc-recordable). For repeat use, you need a CD-RW (compact disc-rewritable). Those of a particular vintage should think of a used CD-R as a cassette tape with the tabs removed -
Red Book is the industry agreed standard for CDs. A CD's specification includes a maximum playing time (including pauses) of 74 minutes and using 16-bit linear PCM at a sampling rate of 44,100 samples per second (44.1KHz). An actual Red Book exists and is part of a series of publications on computer security standards known as the Rainbow Series.