audio set-up

Digital versus analogue….or Bart vs Deano

At Rapallo, Deano and Bart represent 2 different (very subjective) views of the audiophile spectrum: Deano is all about vinyl, analogue, vintage, and stereo. Bart, on the other hand, is a firm believer in digital, CD, SACD, DSD, Dolby surround and DTS:X neural. The rest of the Rapallo team is amused by their passionate discussions about the subject. It seemed like a good topic to investigate and research a bit further, and here are our findings. Some are quite revolutionary, even Bart had to admit….

 

Indeed, for a long time, the scientific statement around digital (CD) recordings and reproduction of sound has been that the dynamic range of CDs is much higher than that of vinyl. In layman’s terms, Dynamic range is the range of volumes of sound in a piece of music. It is measured in decibels. 

Usually, the dynamic range is linked to “signal to noise ratio” (SNR), another technical term to identify the “cleanliness” of the signal coming out of an audio device such as a CD player or a turntable/phono stage. A signal-to-noise ratio compares a level of signal  (what you want to hear) to a level of noise  (what you don’t want to hear). It is most often expressed as a measurement of decibels (dB). The higher the numbers the better. Typically, for a CD the dynamic range is 90 dB versus 70dB for vinyl. The SNR difference is even bigger, 50 dB for vinyl versus 90 dB for CDs.

 

However….Back in 1996 Ron Bauman, who has a degree in Electrical Engineering from Lehigh University, wrote an interesting piece that never really got a lot of attention.  Maybe it is the marketing machine of Sony and Philips, the inventors of the CD player and its format, maybe it was just group think, but in any case, it now appears that a few crucial mistakes were made in “proving” the statement about dynamic range of vinyl versus CD.

Bauman argues that vinyl actually has wider dynamics and he's got the numbers to prove it (unfortunately a few pages "went missing" over the years). In addition, he makes some impressively prescient observations and posits that time domain " may be a more natural frame of reference for audio instrumentation development" (than frequency domain).

Bauman talks about “the myth of the frequency domain”. He makes a very valid and convincing point that when humans listen to music, our ears are not analyzing frequencies, but rather they are picking up changes (of air pressure or sound) in the time domain, not the frequency domain. 

 

Being the electronical engineer that he is himself, it's that last statement that caught Bart’s eye. But what does that mean? It’s the stuff that comes with a lot of complicated maths and calculations drooled over by said engineers, but the logic behind it more or less boils down to this: Bauman argues that when you look at sound in the frequency domain,you look at the sound wave frequency peaks over a period of time. Which is important, right? 

But it’s quite an isolated observation, because a sound wave is so much more than just its peak frequencies. When you look in the time domain, you look at how sound behaves in all its aspects over a period of time; the highs, the lows and every step in between, the amplitude and the phase. Subsequently, this makes it a lot more complicated, when you look at the overall behavior of sound instead of just the peak frequencies. This is exactly why observations in the frequency domain where introduced in the first place: it makes things a lot simpler. BUT Bauman argues that we as humans perceive sound in all its complexities, rather than in its simplified form. And when you think of it, it makes total sense. But easier for the engineers, it is not.  

Long story short, Bauman argues that engineers have been oversimplifying things for their convenience by looking at a sound wave in the frequency domain, rather than the much more complex time domain. In doing that, they have ignored a whole lot of important factors in developing AV products and how the human ear experiences these products. Now why did we not think of that before? Whenever we look at the specifications of amplifiers, speakers, or any audio component, we look at frequency spectrums to get an idea of what the component will sound like. Never do we look at how it behaves in the time domain. 

Which makes the claim that specs only say so much about an AV products all the more valid. (probably because there is no standard in the time domain available in the industry, nor is there agreement on the relevance of it). What’s more, he provides food for thought and a scientific (rather than subjective) basis for discussions about the “warmth” of vinyl sound versus digital recordings.

 

Added to that, Bauman makes a very strong point about how the industry (in the 1980s) incorrectly looked at the individual components in the vinyl setup (turntable, cartridge, phono stage) in determining the dynamic range and signal to noise ratio, rather than looking at the 3 components as a whole and measuring the dynamic range and signal to noise ratio of the whole. When you look at those measurements and compare them with the results from CD players (in the 1990s, of course) then the results are revolutionary to the old adage that CDs have the highest SNR or dynamic range. 

Bauman’s tests are clear: you need a high end vinyl setup to get to the level where it can compete with CDs. 

 

On top of it all, our research made something else very clear: there have been a number of serious blunders made in the music industry ever since the CD was invented. It is unbelievable (actually, it is, because it’s all about the money) how recording studios and big corporations made decisions on digital formats that don’t make any sense or make things worse. The original sampling frequency of 44kHz at 16 bits that Sony and Philips decided on had a very good (scientific) reason. But ever since, the different formats that are out there now for digital music downloads (DSD, WAV, AIFF, FLAC, etc) and the sampling frequencies that they come in (192kHz, 384kHZ etc) are now more a problem than a solution.

Loudness warHow? The amount of poorly converted tracks, or even poorly recorded, is staggering. Too often, studio engineers start changing the original mastered recordings when re-releasing a new master just for the sake of making it sound good on small mobile phone speakers. The renowned mastering engineer, Bob Ludwig calls it the “loudness war”. And we could not agree more. The original mastering respected the dynamic range between quiet and loud parts in a track, whereas these days it is all about a “sausage” of loud sound from beginning till end.

 

After all this, Bart still won’t buy a turntable, though…He is still put off by the fragility of vinyl, the maintenance involved to keep them clean and dust free.(Do we sense a cleaning fobia there?;-)) And he is still immensely irritated by the slightest “crack” or “pop” sound. Digital is still his preferred medium, he just is not so black-and-white about the fact that vinyl can’t offer the same dynamic range that digital does. If you have a high end vinyl setup, you may actually beat it.

Now waddayaknow….

Source:  The above compression diagram shows Metallica's 'Death magic' from the Kings of AR website. Photo credit to Klipsch.