Specifications

Category of
microphone
arrangement
Coincident place-
ment
Near-coincident
placement
Microphones
separated by an
acoustic baffle
Spaced microphones
Principle by which
the stereo effect is
obtained
level differences level plus minor arrival-
time differences
frequency-depend -
ent level and time
differences
arrival-time differences
primarily
Typical setups Double M/S, First-
order Ambisonics
OCT Surround, MMAD,
INA 5, IRT cross
KFM 360 system Decca Tree, Omni Curtain,
Polyhymnia Array,
Hamasaki Square
Geometry
Distance between
microphones
0 cm 15 – 100 cm 15 – 20 cm 100 – 500 cm
Microphone types
used
pressure-gradient transducers (e.g. SCHOEPS
cardioid CCM 4 or MK 4, supercardioid CCM 41
or MK 41, figure-8 CCM 8 or MK 8)
SCHOEPS KFM 360 /
DSP-4 KFM 360
mainly pressure trans-
ducers (e.g. SCHOEPS
CCM / MK 2H), also
possible with cardioids
or wide cardioids
Sonic impression
(depending on
which microphones
are used)
clean, clear, often
bright
natural, clean, clear natural spacious
full low-frequency reproduction when omnidi-
rectional microphones are used
Spaciousness* often limited;
depends on M/S
decoding parameters
natural, transparent,
good depth
natural good, enhanced (can
become exaggerated)
Localization* good; depends on
decoding parameters
very good generally fairly good somewhat indistinct
Size of listening
area*
small; better when
additional delay is
employed
large rather large depends on micro-
phone distances
Envelopment* limited; better when
supplemented by an
A/B pair
good envelopment possible
Downmix compati-
bility
two-channel and / or
mono (!)
two-channel compati-
bility can be good if
considered in the array
design (e.g. OCT 2)
perfect potentially good, but
this requirement must
be taken into account
and the setup tested for
this purpose
132
Surround Techniques
* The statements here are necessarily rather general. The properties of the recording often depend on various parame-
ters which cannot be covered in detail in this list. These properties can furthermore be varied by combining various
aspects of different setups.
This list should be considered as a snapshot of current techniques for surround recording. It may be subject to change.
It is not intended to create dogmas or ”untouchable” recipes for surround recording. The recording engineer and pro-
ducer are needed more than ever to listen, consider and adjust the results obtained.