This blog (when I have time to update it during my downtime working for Shure in the UK) is fast becoming focused on the resurgence of vinyl. So far, I’ve covered vinyls potential in the changing face of music retail, and I also went on to describe the benefits of vinyl in the well-documented loudness war. Taking this into consideration, I thought it was worth highlighting the technical differences between digital formats such as CD’s/MP3, and analogue formats such as vinyl. Audio enthusiasts often praise the merits of vinyl, but what does this all mean to the average consumer – does it really make that much difference?
The Difference Between Vinyl & CD
This is a big topic, but I will try to cover it on a high level. In really simple terms, the answer lies with the differences between analogue and digital. Sound sources are by definition, analogue, so from that perspective analogue is closer to the original sound source and technically superior. If you look at the picture below, you can see a basic demonstration of the difference between analogue waveforms and digital. Notice the fact that analogue is one continuous line, whereas digital appears as a broken block line. This is because digital recordings take a snapshot of the analogue signal at a certain rate (for CDs it is 44,100 times per second) and measures each snapshot with a certain accuracy (for CDs it is 16-bit). Using higher sample & bit rates, will represent result in a more accurate representation of the original waveform and will reduce the amount of information lost and subsequently filled in with random digital information.
Note: This is a simple high-level explanation of the basic differences between analogue and digital, and does not take into account processes such as dithering and correction of resolution. This post covers common reasons for having a preference to vinyl only. For a more in-depth description of the technical process of creating high-quality digital audio – read Production Advice’s post on why there is no stair step in digital audio.
Now… on to the point of this article….
Why 44.1khz for CD’s?
This all essentially comes down to a well know audio theory call Nyquist Theorem, which dictates that in order to sample audio accurately the sample rate should be at least twice as high as the maximum frequency you need to capture, and with full the range of human hearing ranging between 20hz and 20,000hz, you should in theory be able to capture any sound at a high enough quality for even the best of human hearing. Well, it’s not quite as simple as that. But that’s a story for another day – click here for more information on sample rates and Nyquist Theorem
Basically, and before this gets more complicated than I intended – even though CD sample rates capture the full range of human hearing according to Nyquist – many claim there are still some audible artifacts, such as aliasing, which means that analogue recordings are in theory better. However, there are many other factors to consider here, including the fact that digital recordings have the ability to products greater dynamic range without noise floor issues, amongst other advantages. However, advocates of vinyl often praise its warmth and richness.
The Downside of Vinyl
So what’s the catch I hear you ask? Well, analogue audio signals are a representation of physical waveform intensities in a different form, such as voltages on a wire or magnetised particles on a cassette tape. In the case of vinyl, these wave intensities are represented by grooves carved into the record, which mirror the original waveform. In a perfect world, this means that little information is lost when compared to digital samples. However, it’s not quite as easy as that, and unfortunately, if only by physical wear and tear, or from specks of dust, or damage to the disc – analogue formats such as vinyl are subject to noise and static with age. The lesson here – look after your vinyl, and they will reward your ears for much longer!
Audiophiles may bicker over the differences between vinyl or CD, or digital vs analogue, and a well-kept record, played on a great sound system is truly a wonderful thing. But for most people, the benefit of vinyl goes beyond this. It’s about the romance of it all, the procedure of putting a record on, and the joy of the format. In the words of Jack White (and I do love a quote to summarise) “There’s no romance in singing about an I-Pod”