RedShark Summer Replay: Recently there's been a resurgence in sales of vinyl records. We don't really know why. And we think we can prove that vinyl isn't better than digital. Here's how.
We've spent a lot of time talking about whether film is better than video, and whether vinyl is better than digital audio. So much so that you'd think there isn't much more to say on the subject.
Well, first of all, I think there's always something to be said about it. After all, digitisation is the most crucial stage in the creation of digital media (except computer-generated animations, of course - and even these have to be turned back into analogue if we're going to be able to see them!). It's what turns the minuscule scintillations from microphones and image sensors into numbers that we can manipulate and store accurately.
(Just parenthetically, I want to say here that digits don't automatically mean harsh, unsubtle blocky video or audio. With enough of them - 14 bits per colour channel for example, or 32 bit floating point audio, digital can convey far more subtle information about the world than any system that has proceeded it).
But while a lot of what we talk about when we're discussing this is subjective, some of it isn't. Because we can do tests and experiments that at least prove something. What's more, it's the logical structure of these tests that is as important as the subjective assessment of them. I promise that's the most abstract statement you're going to read in this article. So let's move on to the practical details.
What I'm going to stay here applies as much to Film vs Video (when I say video, I mean digital video here!) as it does to Analogue vs Vinyl, but, experimentally, it's probably easier to talk about the audio version of the experiment.
There will be a lot of readers who will disagree with me as they read this. That's OK. I'm not being dogmatic here. I'm just saying how things seem to me. Please, let me know what you think in the comments.
So, here's where we start from. We need to tie a few things down before we get into the nitty-gritty of the experiment, which is actually a very simple one.
Experiment to show that digital is better than vinyl (see explanation on page 2)
Let's be clear about what we mean
Let's start by being clear about terms. Often, when we're talking about audio, people use the terms "Analogue" and "Vinyl" interchangeably, which can be confusing. Vinyl is an analogue medium, but there are other analogue media, like analogue tape.
In fact, it's probably fair to say that the very best analogue tape sounds far better than the best vinyl recording has ever done. It stands to reason: unless a recording is cut directly to disk (and some were and are) then tape will be the intermediary. And analogue tape can sound very good indeed.
If you've never heard studio quality tape recordings, then you might think that tape is hissy and dull. The very best studio recordings (probably using Dolby SR) were superb, and to this day, subjectively, probably can't be bettered, except by high resolution digital recording.
Studio tape recordings sound good because the tape is wide and is run at a high speed. With these conditions, the signal to noise ratio is superb, as is the frequency response.
Vinyl, on the other hand, has a restricted frequency response, dynamic range (if it were too big, the needle would jump out of the groove) and quality that changes from the outer to the inner part of the record.
So, let's focus on Vinyl first. People say that it sounds better than digital, a phrase that, without qualification, is almost meaningless.
Here's a way to make it meaningful, though.
Nobody (well almost nobody) is going to disagree with the idea that the original sound is the best. Let's say it's a jazz group or an orchestra, or a solo guitarist or a rock band. There is no known law of the universe that is going to make a recording sound better than the original.
Well, actually, it might, but not for the purposes of this test, and only in the very narrow sense that the recording might make the sound "sweeter" in some way: a tailing off of high frequencies, mild dynamic range compression, or any number of phenomena that might change the sound in a way that we find pleasing.
But it is certainly not going to be more "accurate" than the original. That would be a logical impossibility.
So here's what I suggest. Let's have a live sound source - any of the above - and record it in two ways. First, via analogue tape and then to vinyl. Second, direct to a digital recorder, capturing at 24 bits and at 192KHz sampling frequency. The to recordings should happen simultaneously, fed from the same microphones. (Any mixing should be done in the analogue domain for the vinyl, and through a digital mixer, with a digital output to the digital recorder.) The digital mixer should be running at the same bit-depth (ie 24 bits - or even 32 bit floating point) and sample rate as the recorder. Analogue to digital conversion should be via a top-end converter like this one that we mentioned in RedShark recently.
Essentially, this is what it's supposed to show. People who say that vinyl sounds better than digital will have to be able to explain this.