In our recent article What Is Your Method For Recoding Stereo - Take Our Poll we offered a choice of six categories, we tried to cover everything in a few choices as is practical, as no-one likes a long survey. We weren’t asking about polar pattern or mic type, just the type of array used. Respondents could choose a maximum of two options if they wished as most people use more than one technique. The question in the survey was simply:

‘Which is your preferred stereo technique?’

• Coincident Pair (e.g. XY, Blumlein)

• Spaced Pair (e.g. AB, Faulkener)

• Mid Side

• Near Coincident (e.g. ORTF, NOS)

• More Than Two Mics (e.g. Decca Tree, LCR)

• Binaural and Ambisonics (e.g. Dummy Head, Soundfield)

The results were as follows:

What Do The Results Tell Us?

When we built this survey we expected that coincident and spaced would be the most popular choices by some margin. This has proved to be the case. However we were less sure about which out of spaced or coincident would be the most popular overall. Some feedback we received was that the choices favoured rock/pop recording over classical techniques. We’re not sure that is the case, for example we were careful to include Blumlein in the examples along with XY, and Decca Tree is very much a classical technique.

The aim of the survey was to reduce the whole variety of approaches to capturing stereo down to as few choices as possible and we did this by grouping the choices according to their key differences, for example Blumlein (crossed fig 8s) and XY (crossed cardioids) both place two mics at the same point in space and capture level differences, hence they are grouped together. You could correctly point out that Mid Side is also a coincident technique, but as the processing required to render a stereo output is different we put that in its own category.

Why Might Coincident Have Been Most Popular?

The popularity of Coincident over Spaced is possibly due to what people are recording. I initially wondered whether the popularity of XY (and I’m sure we can assume that XY is the coincident technique most people are using) was due to the likelihood that most respondents would have access to a pair of cardioid mics, but I suspect that the majority of spaced pair recording happens with cardioid mics too, especially when you factor in drum recordings. The reason I choose coincident over spaced is mono compatibility, especially if the sound source is likely to move during the recording. I suspect the popularity of coincident is a reflection that mono compatibility is still important to people.

Given its relative complexity, it’s good to see Mid-Side in third place. Near coincident is a technique I don’t personally use often but it always surprises me how good it sounds when I do use is. The last two categories are there principally to try to cover the other options without resorting to using ‘Other’. More Than Two Mics covers many options and the recording of large ensembles is where we are most likely to find these used regularly. That being said I regularly use three mics for drum overheads.

Ambisonics and Binaural have always been niche techniques but technology has finally caught up with them in the sense that while previously they were rather ahead of their time, Game audio and Dolby Atmos have revived interest in them. I don’t think they will ever be as popular as the other techniques but Binaural as a delivery format has certainly become far more mainstream in recent years and gathering audio in a channel agnostic format like Ambisonics has a new relevance now that immersive audio is so much more mainstream than it has perviously been.

The fact that we allowed two answers per entry means that there is a limit on the conclusions we can draw from this data. The total number of respondents was 512 and the data totals 776. This indicates that just over half the respondents gave two responses. I’m surprised it was only 50% as I definitely would have answered twice. In case you were wondering my choices would have been Spaced and Mid-side but Coincident would have been a very close third!

The Stereo Techniques - Recap

If you’re unfamiliar with any of these techniques, here is a recap of the graphics from the original post, follow this link to read some additional supporting information.