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Vinyl vs CD – is Vinyl Higher-Resolution?

In the vinyl vs CD debate, I am often asked why vinyl sounds so good and why compact disc (CD) was created, if vinyl was a better medium in the first place? To put this another way – the question might be: “Vinyl vs CD – is vinyl higher resolution?”

This is not a simple question to answer, there is a great deal to consider. What makes a great medium? What makes a better medium? A bad record played back on a bad turntable sounds bad, full stop. But the potential is there with vinyl, with good pressings and great playback equipment, to sound superb, better than CD, better than any MP3 can ever sound and better than even high-res digital. Even with my super-specced up Musical Fidelity Tri-Vista Class A Tube DAC, a good vinyl pressing of the same recording will often sound better – smoother, more relaxed.

Note that we need to consider what metrics we are using. I’m specifically talking here about resolution, NOT noise, or pitch accuracy. Based on those two metrics, CD has the edge and everyone in audio knows that. But one can make a strong argument for the fact that resolution of fine detail, of nuance and of subtle  micro-dynamic and high frequency information that is lost in the digital sampling process, is more important in realistically reproducing music.

You might think of resolution as the ability to discern fine detail, to accurately portray two sounds of slightly differing levels. The simple answer is that, as a medium, vinyl is capable of higher resolution than CD, but we need to examine this in a little more detail.

There are two important parameters to examine when looking at the Red Book standard which defines the technical specifications of CD. These are sample rate and bit depth.

Bit Depth

Looking at bit depth first, CD has a technical resolution of 2 levels, 0 or 1, raised to the power of 16, the number of bits in each digital word and the bit depth specified in the Red Book standard. This gives us 2^16 or around 65,536 possible amplitude levels for any sample. Simply stated, any tone can have 65,536 volume levels.

In this 4 bit digital system, the amplitude of the waveform can be any one of 2^4 levels, or 16 discrete signal amplitude levels. In CD, we have 16 bits, and there for 2^16 possible amplitudes. This gives us greater, but finite resolution – 24 bit is much better!
Sample Rate

Sample rate determines the number of times the digital system captures a waveform, per second. For CD, this was set at 44,100 samples per second. This means that continuous tones in real music are chopped up 44.1 thousand times a second and joined together.

In this diagram, time, on the x-axis, is plotted against amplitude again, on the y-axis. Sampling refers to the snapshots taken in time of the waveform, indicated by each numbered sample point along the x-axis. This is where we lose resolution again, there are never enough samples to fully flesh out the waveform, and there are never enough bits to allow correct expression of the amplitude. We end up with a dot diagram, where our brain interprets and fills in the missing data. This is far from ideal.

Think about bit depth and sample rate – both are finite and limited to a set number of steps or samples, in a given time or for a given sample. Analog systems are not limited in this way at all. Vinyl for example has an infinite number of possible volume levels, within the dynamic range of the medium. Likewise, there is no sampling of waveforms in analog playback, hence high and low-frequency waveforms have the same amount of detail possible in them.

Think for a moment about a high frequency signal, like the sound of a cymbal being hit. This sound will have a range of harmonics and overtones that extend either side of the fundamental. Some of these harmonics will extend to over 20 kHz. Vinyl replay systems allow for the playback of frequencies over 20 kHz, whereas CD does not. This is due to the limitations imposed by the 44.1 K sample rate.

More importantly than the limitation in high frequency response, the 44.1K sample rate means that a 20 kHz signal will be sampled approximately two times per waveform! If you look at the complex shapes and curves of a sine wave for example, you will quickly see that no two points or samples on this waveform are going to allow you to accurately represent it during playback.

This is a fundamental and acknowledged limitation in the resolution of compact disc. This may also explain why most of the criticism of the Red Book format seems to be around high frequency performance, hardness and glare.

There is no escaping that 16 bit 44.1K digital was the best they could roll out in 1982. These days however, 32 bit, 384 kHz digital is where we are at, in terms of playback. The problem is finding sources – recordings and masters – that have that amount of detail in them. They are virtually non-existent. Unless you have the analog master tape of course. Then you have a source with resolution higher than even 32 bit 384 kHz digital. Can you see where this is headed?!

So, CD is technically less resolving of fine level detail and high frequencies than a good vinyl system, but herein lies another caveat. Vinyl is capable of superb technical performance in some areas, but is itself limited in others.

Typically pitch and speed accuracy of vinyl playback is an order of magnitude worse than CD. Turntables suffer from additive speed inaccuracies, meaning that off-centre records and pitch issues with the mother and stamper vinyl are added to playback inaccuracies caused by the record player itself.

Dynamic range of vinyl cannot compete, on paper at least, with that of compact disc. Vinyl offers a usable dynamic range – the difference between the softest and loudest sounds that can be accommodated within the medium – of around 70 dB. Compact disc offers a dynamic range of around 90 dB. The scale is logarithmic, so 20 dB more is not 20% more, it’s much, much more!

Compact disc also offers a technically flatter frequency response which is not subject to the resonances and wiring effects of magnetic cartridges of a turntable. There is also much less distortion, again on paper, than vinyl systems are capable of. The CD player itself theoretically introduces much less in the way of noise and distortion than a record player does.

AND YET, we have the curious situation where, given identical recordings, made from the same master, played back from vinyl and CD pressings from the same era, the vinyl recording very often sounds better! Isn’t this interesting? The conclusion one must reach is that, despite the shortfalls in dynamic range, pitch accuracy and distortion, vinyl’s inherent higher resolution is the key to why it sounds better.

8 thoughts on “Vinyl vs CD – is Vinyl Higher-Resolution?”

  1. I would also add that, the article seems to be trying to find a conclusion by working backwards from the technical specifications of the end formats which is a fools errand.

    Aside from the obvious differences like surface noise, crackle and badly tuned tables any tangible differences are likely further up the chain, even when they are the same master.

    Optimisations for vinyl playback can happen after the master output for example. In the end unless you were there there’s no way to know for sure.

    Add to that each turntable imposes its own character on the sound (turntables arerfairly far from linear, relatively), and you have some unpredictable outcomes.

    1. Hi Daniel, thanks for your comments, though I ask that all commenters please remain respectful. My site is a place to learn and share, respectfully 🙂

      So, no fools errands here, what I wrote was carefully considered, aimed to inform and educate and supported by a huge amount of listening experience, + science!

      This article examines the formats on their merits. This invariably requires looking at the science to gain a better understanding of what we hear.

      The science supports my experience listening to albums across formats on an enormous range of gear and what so many other people with good gear report. Vinyl is capable of higher resolution, and incredibly, despite the complexity of the playback chain.

      There are of course lots of variables. I’m lucky to have great gear and I’m lucky to work on and listen to great gear for a living. As you say and as I point out, there’s lots of variation possible in the chain from recording and mastering to playback and therefore what one gets at the end. Ultimately though, that’s not what this piece was about!

  2. I firmly believe that when you listen to any album, what you are hearing is a long process which goes far beyond the end format which you choose to listen to it on.

    Anyone who favours one end format over another religiously is crazy and is not judging the end product, but hanging on to some preconceptions of how things should sound.

    Note that, this only applies to being a consumer where you have no control over the process before you get the final product.

    As a creator of content, there’s a reason why analog died out of common usage and high res PCM is now the standard. On pretty much any metric that matters it’s better for creators. But that doesn’t mean that someone who chooses to use an analog process can’t make a better product simply by being better at their job.

    I also don’t think that spending a bajillion dollars on a vinyl setup will make it always sound better that digital or vice versa. Each album needs to be viewed on a case by case basis as to which is the better made product. For me that usually ends up being digital but there are a few vinyls which outshine their digital counterparts.

    1. I disagree with much of what you’ve written here also, but that’s ok! For me, it’s about what I hear and the science. No place here or anywhere in my opinion for religiously held beliefs. It should always be based on evidence. Vinyl almost always sounds better to my ears, and to those of many others, but obviously not all people. Let’s keep enjoying listening to music, that’s what this really all about!

  3. I also firmly believe that some people feel, because you can get the odd pop, click and other noise artefacts when playing vinyl – even good vinyl on good kit, that they simply dismiss the notion that the music can sound better when played back from an LP.

    They can’t accept that you can train your senses to listen through the odd click and pop and focus on the music. I don’t think any amount of healthy scientific debate will ever change this.

    IMHO of course 🙂

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