The debate over whether analog or digital sound is preferable is very delicate, about as resolvable as arguing about which is the better sport. There are people who swear by either side. On one side there are the high-end audio enthusiasts who believe analog audio is superior because it captures the true essence of the sound wave, while on the other side, there are those who are convinced that advances in audio recording will produce digital sound equally as pure. The final sound quality ultimately depends on the quality of both the recording and the sound system.
Analog sound
Sound itself is a continuous wave; it is an analog signal. This means that one cannot detect the precise moment the pitch changes. Capturing this continuous wave in its entirety requires an analog recording system; what the microphone receives is exactly what’s written onto the vinyl disk or cassette. Analog is believed to be the true representation of the sound at the moment it was recorded.
Digital sound
Digital sound is not a recording of the actual sound, but rather a combination of binary code, the utmost simplest machine language of zeros and ones, representing the sound’s intensity and pitch at precise intervals with relative accuracy. The binary code is arranged in a specific pattern informing the computer how to recreate the sound itself. It is not a single wave the way analog sound is, but rather a composite of multiple segments representing consecutive moments of intensity and pitch. Where an analog recording is similar to the fluency of film, a digital recording is stop motion photography.
Digital sound is missing bits of the sound wave, but as digital recording improves, the curve will smoothen out and begin to resemble the analog sound wave. Image courtesy of Centerpointaudio.
Recording method
Sound waves can be stored on an analog master record and then transformed to a digital audio format using an analog-to-digital converter (ADC), or it can be recorded directly on a digital medium. Once the audio is played the digital signal is converted back into an analog sound wave using a digital-to-analog converter (DAC). Having suffered compression and then expansion, the integrity of the original sound is compromised.
Assuming you’ve invested in a high-quality sound system that’s compatible with both the digital and audio formats, the superior choice depends upon which one was used to make the initial recording. The goal is to select a format that undergoes the fewest amounts of conversions, meaning if an album was recorded as analog, the sound wouldn’t need to convert to digital before being converted back to analog since it can be played directly on the analog system.
Image courtesy of retro-vintage-bazaar.
Audiophiles, high-quality sound reproduction enthusiasts, will swear that the purest sound originates from a vinyl record played on an analog sound system. This seemingly reproduces the exact sound wave that was heard the day the record was created as there is no conversion taking place. The analog pairing is not complete without a high-quality sound system: speakers, amplifier, and all – having the best of the best will cost you.
Digital is catching up
The difference between analog and digital audio is no longer so cut and dry. Innovations in analog-to-digital conversion methods have improved the accuracy by which analog sound is replicated. The DVD audio format as one example, allows greater data storage and thus a larger sample rate and bit size. Stop-motion photography can be made into film with a high-enough frame-rate after all. This translate to the digital curve representing the digital sound wave smoothening out.
Sample rate
The sample rate represents a series of snapshots per second attempting to recreate the sound wave. Obviously, the higher the sample rate, the smoother the digital representation of the sound wave will be. CDs are sampled at 44 kHz (kilohertz), meaning 44,000 snapshots per second. DVD audios have a significantly higher sample rate of 192 kHz, so it is clearly a superior medium over the CD and therefore a closer depiction of the sound wave stored on an analog medium.
Bits
Bits refer to the accuracy of the sample, or the amount of detailed stored within each sample. The higher the number of bits, the better the audio quality is. CDs audio is considered inferior to the vinyl disc because of it has 16-bit accuracy which is very limited. DVD audio has 24 bit accuracy, thereby being an improvement over CDs and a step closer to matching vinyl sound quality.
Mp3’s don’t do music any justice
The mp3 format was created for sole purpose of compressing audio as much as possible while still retaining a close enough impression of the original analog sound. The format was never intended to be used with high-end audio equipment. The sound quality is far more compressed than even a CD and is inferior at accurately reproducing the sound frequency of the sound.
The mp3 is similar to a low-resolution picture. You can’t make out all the detail clearly, but more than enough to formulate an impression of the overall picture.
Do you prefer digital or analog sound? Leave a comment below.
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