Tag Archives: audio

The Bullshittery Of Audio Jargon

The topic of audio recording is vast and open-ended, and discussion about associated equipment in particular often gives rise to much heated debate with respect to perceived differences in the sonic performance between devices. It is not uncommon for hostile discussions to be waged pitting the minutia characteristics of this device against that, with all parties using increasingly elaborate language to define their subjective auditory experience, yet in the process obfuscating any real scientific analysis in favour of regurgitating “buzz” words that, when examined, actually fail to reveal anything helpful about the nature of the device in question. “Warmth”, “openness”, “air”, “punch”, “creaminess”, “sheen”, “silkiness”, “purpleness”, “dogturdidness”; fluffy terminology of this nature can often be observed in industry magazines (as some notable culprits are particularly guilty of), where vast word salads are served up in an attempt to suitably bewilder the reader into believing some imposed perception about a given piece of equipment. Whether it is an industry effort to create brand association with generic “good sounding” Barnum statements, or simply sloppy journalism in which authoritarianism comes from using words that everyone is too confused to question, the amount of bullshit I witness people talking on a regular basis goes to show how successful this method is.

I find language of that nature problematic for several reasons, not least because it denies us, as students of audio recording practices, access to scientific truths with regards to our field, where discussion of imparted harmonic content via signal distortion is much more helpful than fogging the issue under a linguistic cloud of subjective terminology and thereby propagating marketing myths about the necessity of over-priced equipment. It is no doubt a valuable weapon across all levels of the audio equipment industry, each brand justifying the apparent necessity of its newest model by using words that no one really understands. It’s interesting how readily we accept this lack of clarity in the discussion of audio, and how encourageable everyone seems to be to jump on the bullshit bandwagon. Note how we don’t accept this terminology in discussion of equipment where the scientific validity of their specifications really matters – I’m sure no FMRI scanner was sold on the basis of the “punch” of the scan or the “warmth” of the images produced. We can more readily accept fuzzy jargon in that context as obviously ridiculous and unhelpful.

“Brilliance”, anyone?

One of my audio recording heroes is Ethan Winer – musician, acoustician, and owner of the acoustic treatment company RealTraps – Ethan is somewhat notorious for his efforts to debunk tenacious myths prevalent among recording enthusiasts, whilst grounding his discussions in empirical scientific analyses, thereby abstaining from and often criticising the use of ambiguous subjective terms. I highly recommend his book “The Audio Expert” in which he talks about this very topic:

“Some of the worst examples of nonsensical audio terms I’ve seen arose from a discussion in a hi-fi audio forum. A fellow claimed that digital audio misses capturing certain aspects of music compared to analog tape and LP records. So I asked him to state some specific properties of sound that digital audio is unable to record. Among his list were tonal texture, transparency in the midrange, bloom and openness, substance, and the organic signature of instruments. I explained that these are not legitimate audio properties, but he remained convinced of his beliefs anyway. Perhaps my next book will be titled Scientists Are from Mars, Audiophiles Are from Venus.”

With this in mind then, allow me to demonstrate the principle of audio bullshit in action. As I came to undertake an investigation into the sonic differences between several different microphone preamps (post on that soon), I encountered a 2007 article from Sound On Sound in review of the Neve Portico 5012 Dual Microphone Preamp. As my curiosity led me to probe how such a device can justify a £1,400 price tag, one sentence in particular proved to be such an excellent demonstration of the ambiguity of industry terminology that I was inspired to finally write this blog post, hailing my discovery as a gold standard of audio bullshittery. Let’s have a look:

“The 5012 […] has a full bodied, solid sound that gives that slightly larger-than-life character that is the trademark of a really top-class preamp. It sounds clean and detailed in normal use, without that edgy crispness that can detract in some designs…

When the Silk mode is switched in, the sound becomes a little smoother, rounder, and sweeter still in the upper mids. The high end gains a little more air, and the bottom end becomes a tad richer and thicker.”

Terms like “larger-than-life” and “edgy crispness” are rampant when describing microphone preamps, analogue-to-digital converters and other studio essentials, yet they say nothing useful whatsoever about the actual, verifiable sonic characteristics of the device, instead simply propagating the usage of these vague terms and using them as flimsy justification for impressionable enthusiasts to feel anxious about the “below-par” consumer grade equipment they are currently using, and therefore encouraging them to unnecessarily part with not insignificant sums of money, thereby continuing the trend. That’s not to say of course that there is no value in “high-end” gear such as this, however I would prefer that its usage could be justified in more certain terms than these floppy, nothing words that we all have to keep grappling with. In my experience it’s always worth pushing for clarification via language that is arrived at through scientific consensus so that we can all be on the same page in terms of our expectations. This is the best prophylactic available against the tech-heads who claim authority by asserting that their £X,000 device sounds “sweet”. Chances are, they’re talking bullshit.

Advertisements

Comb Filtering In Drum Overhead Microphones

Recording drums in a small room is a problem that any engineer not blessed with an infinite budget must deal with at some point. Among the difficulties inherent in this scenario is the problem of comb filtering in the audio signal due to the microphone’s proximity to a boundary, i.e. the ceiling or a nearby wall. For example, if a singer sang into an omni-directional microphone placed 1 metre from a reflective wall or surface, the sound of their voice would hit the mic but also carry on past it, hit the wall, rebounding back and re-entering the mic about 6 milliseconds after the direct signal.

boundary

 

This is exactly the right amount of time for the frequency components around 85-86Hz to come back close to 180° out of phase with the direct signal. There will not be total cancellation, since the rebounded signal will be weaker and because the sonic characteristics of the singer’s voice are constantly changing, but the effect may still be significant.

frequencies

 

Rounding down to 85Hz, at 170Hz the reflection will come back in phase and reinforce the 170Hz components within the direct signal. At 255Hz it will be out of phase again, and at 425Hz and 595Hz, and at intervals of 170Hz all the way up the frequency spectrum. This is known as “comb filtering”, due to the regular series of peaks and notches across the spectrum. It sounds phasey and generally undesirable.

This effect is demonstrated in this video, where a drum overhead microphone is moved towards a nearby boundary and back again. The comb filtering artefacts are clearly audible in the recorded signal. The first microphone – a Royer R121 ribbon mic – clearly suffers from this effect with great prominence given it’s bi-directional polar pattern, and thus greater susceptibility to rear reflections. The second mic – an Audio Technica ATM450 – reveals itself to be less harshly affected due to its cardioid polar pattern. This then demonstrates the importance of microphone selection with regard to its placement within a recording environment, as well as the importance of placing the mic as far from boundaries as possible, or, when this is not feasible, treating nearby surfaces with good quality acoustic absorption in order to eliminate as many reflections as possible. A combination of absorption and diffusion is most effective.

 

Many thanks to my beautiful assistant, Bebe Bentley, for helping me with these tests. Check out her excellent work in film and moving image on her Vimeo page.