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MK --Microphone Capsules
CMC --Microphone Amplifiers
User GuideColetteModular System
ColetteModular System
Table of Contentspage
System Overview 2CMC -- Microphone Amplifiers 3
Phantom Powering 5Technical Specifications 7Notes on Electromagnetic Compatibility 7Block Diagram 8
MK -- Microphone Capsules 9Capsule Selection 9Attaching a Capsule 9Basic Characteristics of Transducers 10Suggested Capsules for Specific Applications 11Pressure Transducers 12Boundary-Layer Microphones 13Pressure Gradient Transducers 14
Specifications for Complete Microphones 20Care and Maintenance 21Possible Problems 21Warranty 23
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
System Overview (Extract)Co
lett
e M
odul
ar S
yste
m
2
inlin
e fil
ters
inlin
eat
tenu
ator
mic
roph
one
caps
ules
atte
nuat
or
swiv
el
low
-cut
filte
r
mic
roph
one
ampl
ifier
s
...
RC KCActive Tube
(special version)
MK PAD GVC
KCActive Cable
CUT 60
Signal:balancedunbalanced
TR 200 KCg Active Table Stand
RCActive Tube
LP 40 Ulow-pass filter
Active Accessories
CMC 6, P12 / P48
CMC 3, P12
CMC 5, P48
LC 60, LC 120low-cut filters
OSIX CIelastic suspensionwith Active Cable
e.g. microphonepreamplifier ormixer
MDZ 10,MDZ 20
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
CMC -- Microphone AmplifiersM
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Dear customer:
Thank you for choosing SCHOEPS CMC(”Colette”) Series microphones. This is the mostextensive and diverse modular microphonesystem in the world, offering the highest pos-sible professional sound quality in an extremelywide range of practical configurations. A systemoverview is shown on page 2.
Colette Modular SystemA condenser microphone is formed by thecombination of two main components: a cap-sule and a microphone amplifier:
The capsule is the component which convertssound waves into a varying electrical voltage.It determines the directionality and, for themost part, the sound quality of the microphone.The amplifier is the other main component,with the circuitry needed to accept externalpowering, polarize (charge) the capacitivecapsule, obtain the audio signal from it, andconvert that signal to one which is balancedand low-impedance.
Microphones of the Colette Series are mod-ular: Any type of CMC microphone amplifiercan be used with any type of Colette capsule.Approximately 20 different capsule types (MK --)are available for wide-ranging applications,and several types of amplifier (CMC --) areavailable for various powering and connectionschemes.
In addition, the practical value of a ColetteSeries microphone is greatly enhanced byColette ”Active Accessories” – special goose-necks, ultra-thin cables or narrow extensiontubes which allow the capsule to be separatedsome distance from its amplifier and placedunobtrusively, as if it were a miniature micro-phone. Colette Active Cables are often usedto help conceal microphones for film and videoproduction, while Colette Active ExtensionTubes have become a mainstay of concertamplification, recording and broadcasting. The
active circuitry in these accessories converts theaudio signal to lower impedance directly atthe capsule, so that there is no loss of soundquality:In the following pages you will find technical
information, application hints and advice con-cerning the care and maintenance of thesemicrophones. We begin by considering theCMC amplifier and how to power and connectSCHOEPS condenser microphones; the secondpart of this manual concerns the capsules ofthe Colette Series. For information on acces-sories (including Active Accessories), please seeour main catalog or visit www.schoeps.de.
CMC -- Microphone Amplifiers ...are distinguished by:– flat frequency response– low noise and distortion– balanced, symmetrical, very low-impedance
output – ability to be used with very long cables
(e.g. several hundred meters) – versions for various powering schemes
Several standard versions are available. Allfeature a symmetrical, class-A output stagewhich uses neither coupling conden sers nor anoutput transformer. This leads to a low outputimpedance, insensitivity to electrical interfer-ence, low distortion and light weight.
CMC amplifiers are electrically active com -po nents which require operating current. Thiswill most often be supplied by the inputs of amixer, preamplifier or recorder that has suitablemicrophone powering built in. Otherwise, astand-alone microphone power supply ofproper type can be used.
Standard VersionsFour standard models of CMC amplifier areoffered to fit the specific type(s) of microphonepowering which the user expects to encounter.Variants of these types are also available, offer-
MK-- CMC--
+
+ +ActiveAccessories
ing different output levels and/or extendedfrequency range. Each amplifier works only withthe specific type and voltage(s) of power ingfor which it is designed. Please note: The two amplifiers in a stereo pairof CMC microphones should be of the sametype. For critical applications, pairs of capsulescan be selected at the factory for pre ciselymatched sensitivity and frequency response.(A small extra fee is charged for this service.)
Most modern, solid-state professional micro -phones use a standardized powering schemeknown as ”phantom powering,” and mostrecording equipment offers a 48-Volt supplyfor such microphones. Some equipment, how-ever, provides a 12-Volt supply for phantompowering, or can be readily modified to providesuch a supply. The SCHOEPS CMC 6 amplifierseries can work with either voltage, switchingits circuitry automatically to the correspondingmode of operation. It maintains the same levelof performance in either mode, while drawingonly the necessary amount of current from thephantom supply.
Note that the CMC 6 is designed to workwith standard 12-Volt or standard 48-Voltphantom powering, but it is not a ”12-to-48Volt” microphone. Any input to which it isconnected must implement one of those twostandard phantom powering methods. Notonly must the supply voltage meet the stan-dard; the resistors must be correct as well.
For applications in which it is certain that only48-Volt or only 12-Volt phantom poweringwill be used, the CMC 5 and CMC 3 (respec -tively) remain available at slightly lower cost.The CMC 6 offers greater flexibility in poweringas well as superior immunity to radio-frequencyinterference; it is also the only amplifier modelwhich can be delivered in the special ”xt” ver-sion (see description under ”Special Versions”below).
From an audio standpoint, the most signifi-cant difference between the CMC 6 and theCMC 3 or 5 is the response at the very lowestaudio frequencies: The standard version of theCMC 6 has a 12 dB/octave rolloff below 20 Hzas a protection against infrasonics, while the
stan dard version of the CMC 3 or 5 has a 6 dB/ octave rolloff below 30 Hz. Any CMC amplifiercan be specially ordered, or modified afterdelivery, for any desired rolloff frequency withinreason; please see the description of the CMC”linear” version for further details.
In general if a 48-Volt microphone is con-nected to 12-Volt phantom powering, no dam-age will occur but the microphone will not workproperly. On the other hand a CMC 3 couldbe powered safely and effectively by a 48-Voltphantom supply if it can provide 11 mA permicrophone. But that current exceeds what isrequired for standard 48-Volt phantom power-ing, and unfortunately many existing suppliesdo not even meet the standard. Therefore thismode of operation should not normally berelied upon.
Special Versions
CMC 6 U”xt” – the 40 kHz versionThis variant is indicated by the letters ”xt”engraved on the output socket. When an ”xt”amplifier is used with any axially-addressedColette capsule, the response range of themicrophone will extend beyond 40 kHz. Theresponse above 10 kHz will also be elevatedslightly. Specific frequency response curvescan be seen in our main catalog or on ourWeb site, www.schoeps.de .
CMC “+5 dB” The sensitivity of a microphone with this ampli -fier variant is 5 dB above the normal type,while the equivalent noise level is somewhatgreater. The increased output levels can helpto raise a microphone's signal above the inputnoise level of the equipment to which it isconnected, especially when sound levels arelow to moderate. However, the overload limitof that equipment, and of the microphoneitself, will also be reached 5 dB sooner.
CMC ”linear”CMC microphone amplifiers normally have arolloff in response below 30 Hz (20 Hz in theCMC 6) to guard against infrasonic distur-bances from various sources such as vibration
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Types of Microphone AmplifiersM
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and air motion. However, when using pressure(omnidirectional) transducers, particularly withdigital recording, it can be desirable to pick upfrequencies even lower than 20 - 30 Hz. Thespecial technology of the CMC microphoneamplifiers makes this possible; on request wecan deliver microphone amplifiers with responseextending as low as 3 Hz.
For live recording, however, some caution isadvised with respect to infrasonics. Since pres-sure transducers can pick up very low fre-quencies, ventilation systems in large spaces(churches, concert halls) or traffic rumble cancreate a problem. With pressure gradient trans -ducers the risk is even greater. They are farless sensitive to very low frequency sound, butrespond much more strongly to low-frequencymechanical stimuli such as air currents andsolid-borne noise. Such signals may be belowthe audible range, but they can overload pre-amp inputs, particularly those that haveundersized input transformers.
Phantom Powering (DIN EN 61938)(formerly DIN 45 596)
”Phantom” powering is a standard method ofproviding the operating current for a micro-phone's circuitry through ordinary two-conduc-tor shielded cable. Precisely equal DC flows inboth modulation leads, making it ”invisible”and harmless to most balanced microphonesthat don't require such powering (e.g. mostdynamic microphones, including ribbons).Exceptions are quite rare. The only likely casesin which standard phantom powering will en -danger a balanced microphone (e.g. a ribbon)are if a microphone cable, con nector or adapteris defective or wired in a non-standard way,such that one modulation lead of the micro-phone is shorted to ground at DC while thepowering is on. If a microphone is connectedto such a cable with the powering turned on,impulse current will flow through its coil orribbon, possibly causing damage.
Fig. 1 shows the only valid 48 V and 12 Vphan tom powering circuit (abbreviations: P48and P12) that can be realized with resistors as
opposed to a center-tapped input transformer.This illustration is based on the internationalstandard document EN 61938, ratified in1997. Our microphones are developed andtested with power supplies that con form tothe requirements of this standard. Proper oper-ation with non-standard power supplies can-not be guaranteed. Circuit arrangements thatdeviate from the standard can cause opera-tional problems (i.e. distortion or even gaps inthe signal), particularly at high sound pressurelevels or in the presence of strong wind noise.Such problems may often seem to defy analysisuntil their real cause is discovered.
The permissible tolerance of the feed resistorvalues as such is ±20%. However, the differ-ence between the resistors of any one pairshould be less than 0.4% (i.e. 27 Ohms for 48-Volt phantom powering with 6.8 kOhm).This close matching is necessary to maintainadequate common mode rejection. It will alsoprevent significant DC from flowing throughthe primary of the input transformer (if one ispresent) and causing distortion or reduceddynamic range.
A microphone designed for 48-Volt phan-tom powering could draw as much as 10 mAaccording to the standard. A SCHOEPS CMC 5or CMC 6 will draw about 4 mA even whenActive Accessories are used; this falls wellwithin the limit set by the prevailing standard.There are certain commercially available powersupplies, preamplifiers, and mixing desks –mostly older, but some more recent – whichfail to meet this standard and hence may notbe able to power SCHOEPS microphones ade-quately. Where doubt exists, equipment shouldbe checked to verify its suitability for profes-sional work with SCHOEPS microphones. Onpage 8 a method is described for checking aphantom supply quickly and easily.
For P12 the standard allows a current of 15 mA. A SCHOEPS CMC 3 will draw 11 mAwhile a CMC 6 needs 8 mA at 12 Volts.
Fig. 2 shows a bal an ced but groun ded am -pli fier in put. In this case eit her a trans for mer(see fig. 1) or ad di tio nal ca pa ci tors ha ve to bein ser ted in the au dio li ne.
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Phantom PoweringM
icro
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SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Phantom PoweringM
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of the microphone must still connect to itsphantom power supply.
Simultaneous Connection to Multiple InputsIf one microphone must be connected to mul-tiple inputs simultaneously, an active micro phonesplitter should be used in order to preservethe loading and powering conditions for themicrophone, and to prevent interference.
Maximum Cable Length Cable lengths of several hundred meters arepossible; Colette Series microphones are some -times used with cables as long as 500 m (over1/4 mile!). But the practical limit depends onthe electrical capacitance of the cable, whichis sometimes an unknown quantity. The lowerthis capacitance is per unit length, the longer
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* see note in the text concerning tolerances
(4), (5) only with XLR-5connectors of stereo inputs
Fig. 2To add phantom powering
to a balanced, grounded,
transformerless input, capa -
citors must be inserted into
the signal lines and polariza-
tion resistors provided as
shown.
*
*
*
Fig. 1Input with transformer
(or balanced, floating trans-
formerless input)
XLR-3-connector
XLR-3-connector
* recommended values:C: 100μF, 63V; R: 22kΩ, 1%
R*
Unbalanced OperationUnbalanced operation of CMC microphoneamplifiers is not recommended; both noise andvulnerability to interference will be increased.If possible, an unbalanced input should be bal-anced with a high-quality microphone inputtransformer. That will also allow the signal leadsfrom the microphone to be balanced, for bestrejection of interference.
If such an arrangement is not possible, how-ever, a CMC microphone may be operated inunbalanced mode by taking the signal frompin 2 via a coupling condenser with a value asshown in Figure 2 above. The signal from pin 3must be left unconnected; do not short it toground. This ”unbalancing act” must occurbetween the power supply and the preamplifierinput, however, since naturally all three pins
shield
shield
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Technical Specifications, Electromagnetic CompatibilityM
icro
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Amplifier type Powering Current Impedance Low-cut consumption frequency (-3 dB)
CMC 6U / 6Uxt: 12 V phantom 8 mA 25 Ohms 20 Hz 48 V phantom 4 mA 35 Ohms 20 Hz(automatic switchover)
CMC 5U: 48 V phantom 4 mA 35 Ohms 30 HzCMC 3U: 12 V phantom 11 mA 20 Ohms 30 Hz
Polarity: Increasing sound pressure on the microphone's 0° axis produces a positive-going voltage at pin 2.
Maximum output voltage: 1 V (at 1 kHz and 1 kOhm load resistance)Minimum recommended load resistance: 600 Ohms (A load resistance below this value will par-
ticularly reduce the maximum output level.)The other technical specifications depend on the choice of capsule – see page 12 ff.Length: 116 mm (incl. 3 mm capsule thread)Diameter: 20 mmWeight: 65 – 68 g, depending on typeSurface finish: matte gray (g) or nickel (ni)
1) Keep both the microphone and the cableaway from sources of interference such asmonitors, digital equipment (computers), RF emitters (mobile phones), power trans-formers, power lines, SCR dimmers, switch-ing power supplies etc.
2) Use only high-quality cables with a highdegree of shield coverage.
3) Keep all cables as short as possible.
4) Dress audio cables away from power cables.If they must cross, it should be at right angles.
5) At the preamp or mixer input, the shield ofthe microphone cable should connect tochassis ground in the shortest way possible.If necessary, this coupling can be capacitive.
the cable can be. All SCHOEPS cables havevery low capacitance (100 pF/m between theconductors).
The main risks with excessively long micro-phone cables are losses at high frequenciesdue to cable capacitance, reduced ability tohandle very high sound pressure levels, andincreased likelihood of picking up interference.
No tes on Electromagnetic Compatibility SCHOEPS CMC microphone amplifiers are virtually immune to magnetic, electric andelectromagnetic fields. This is particularly truefor CMC 6 amplifiers made since 2004; theycan be recognized by the gold-colored shieldplate in their output connector.
Due to the wide dynamic range of studiomicrophones, the smallest signal amplitudesare in the microvolt (1/1,000,000 Volt) range.Cable shielding and the grounding scheme ofthe preamp or mixer input are also crucial.Thus no microphone can ever be immune toall possible disturbances under all circumstances.But the following suggestions can help toreduce the likelihood of picking up noise:
7
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Block Diagram of the CMC 3, 5, 6 Microphone AmplifiersM
icro
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Cap
sule
MK
--
Cap
sule
MK
--
Impe
danc
eco
nver
ter
Out
put
stag
e
DC
/DC
conv
erte
rRe
gula
tor
EMI f
ilter
e.g
. cab
le K
C -
- o
rtu
be
RC
--
Act
ive
Acc
esso
ries
: 314 2
31
31
31
4 2
3 1 Scre
en
-Pha
se
+Ph
ase
XLR
-3C
onne
ctor
2
3 12
3 12
Cen
ter
cont
act
( )
Inne
r rin
g (0
V)
Mid
dle
ring
(+60
V)
Out
er r
ing
(+6,
2 V
)
Mic
rop
ho
ne
cab
le
Mic
rop
ho
ne
Am
plif
ier
CM
C -
-Ph
anto
mp
ow
erin
g
Us=
+48
V
R s=
6.8
kΩ
R s=
6.8
kΩ
∼ ∼
Prea
mp
li -fi
er,
reco
rder
or
mix
ing
des
k
41 2 3
* *
**
∼ ∼31
Impe
danc
eco
nver
ter
scre
en
-pha
se
+ph
ase
XLR
-3co
nnec
tor
XLR
-3co
nnec
tor
Pin
1:sc
reen
(GN
D)
Pin
2:+
phas
ePi
n 3:
–pha
seBo
ttom
vie
w
(as
the
pins
are
see
n)
12
3
mitt
ed t
oler
ance
s, t
his
curr
ent
shou
ld b
e be
twee
n 5.
9 an
d 8.
5 m
A D
Cfo
r P4
8, a
nd b
etw
een
15 a
nd 2
1 m
A D
C f
or P
12.
Not
e: W
ell-d
esig
ned
phan
tom
pow
er s
uppl
ies
mus
t to
lera
te a
t le
ast
ate
mpo
rary
sho
rt c
ircui
t w
ithou
t da
mag
e; a
n un
bala
nced
con
nect
ion
(whi
ch is
occ
asio
nally
nec
essa
ry) w
ould
cau
se t
he s
ame
curr
ent
to b
edr
awn.
To
be s
afe,
how
ever
, do
n't
leav
e th
e sh
ort
circ
uit
in p
lace
long
erth
an n
eces
sary
.2)
Mea
sure
the
DC
vol
tage
s on
the
mod
ulat
ion
lead
s w
ith a
mic
roph
one
conn
ecte
d, e
.g.
by o
peni
ng t
he c
onne
ctor
she
ll of
the
cab
le.
The
two
volta
ges
(fro
m p
in 2
and
pin
3 t
o pi
n 1)
mus
t be
iden
tical
. With
a C
MC
5or
CM
C 6
and
a 4
8-Vo
lt su
pply,
the
y sh
ould
be
abou
t 34
Vol
ts (
min
i-m
um =
30
Volts
). Fo
r P1
2 th
is is
8.3
Vol
ts (
min
imum
7.3
Vol
ts)
with
aC
MC
3,
and
9 Vo
lts (
min
imum
8 V
olts
) w
ith a
CM
C 6
.
+Ph
ase:
An
excu
rsio
n of
the
dia
phra
gm t
owar
ds t
he b
ack
elec
trod
e (p
osi-
tive
pres
sure
pha
se)
lead
s to
a p
ositi
ve s
igna
l at
this
pin
.*m
atch
ed p
air;
see
pag
e 5
** H
ere
are
two
sim
ple
met
hods
for
ver
ifyin
g co
rrec
t ph
anto
m p
ower
ing.
Thes
e m
easu
rem
ents
sho
uld
be m
ade
at a
n un
used
inpu
t. R
educ
e th
ech
anne
l gai
n to
pro
tect
loud
spea
kers
, et
c. If
mic
roph
ones
are
con
nect
edto
oth
er in
puts
at
the
sam
e tim
e, n
o su
bsta
ntia
l diff
eren
ce s
houl
d oc
cur
in t
he r
esul
ts.
1. M
easu
re t
he o
pen-
circ
uit
volta
ge b
etw
een
grou
nd (
pin
1) a
nd e
ither
pin
2 or
pin
3 o
f th
e X
LR in
put.
Giv
en t
he p
erm
itted
tol
eran
ces,
thi
svo
ltage
sho
uld
be b
etw
een
44 a
nd 5
2 V
DC
for
P48
, an
d be
twee
n 11
and
13 V
DC
for
P12
. Th
en,
mea
sure
the
sho
rt-c
ircui
t cu
rren
t be
twee
ngr
ound
(pi
n 1)
and
eith
er p
in 2
or
pin
3 of
the
XLR
inpu
t. G
iven
the
per
-
Nom
inal
vol
tage
gai
n:
stan
dard
CM
C a
mpl
ifier
: -2
dB,
”+5
dB”
vers
ion:
+3
dB.
MK -- Microphone Capsules
Which is the Best Capsule for ... ?Only in rare cases can ”the” correct micro-phone be chosen unequivocally. The recordinglocation, the positions of sound sources andthe microphone, the atmosphere of the musicor other program material and the desiredeffect must all be considered. Any absoluteprescriptions would thus be of limited value atbest. How ever, we would like to offer someideas to guide the choice that must be made.
Our RecommendationsThe most commonly used pattern for medium-distance pickup is the cardioid (MK 4 or MK 4V).However, there may be good reasons to makea different choice. Some examples:
– Greater directivity may be required, either forthe sake of a ”drier” recording or to sup-press sound from adjacent instruments. Inthis case we recommend the supercardioidMK 41 (as long as no nearby sound sourceor P.A. loudspeaker is directly behind themicrophone's rear lobe).
– For a broader pickup pattern, with very nat-ural sound quality for sound arriving at thesides of the microphone and more extendedlow-frequency response, we recommendthe MK 21 wide cardioid.
– For essentially perfect pickup of low-fre-quency information and room sound, werecommend the omnidirectional MK 2H orMK 2S (for moderate miking distances).
– When using directional microphones withvery close placement, proximity effect mustbe compensated with a bass rolloff. This isespecially true when miking instruments.For voice, try the MK 4XP or MK 4VXP. Forinstruments the omnidirectional MK 2 maybe of interest (no proximity effect, low sen-sitivity to ”popping” or solid-borne noise);for grand piano, the BLM 03 C.
– For very distant miking and/or as an ”ambi-ence” microphone, with essentially perfectbass response: omni MK 2XS.
– For outdoor recording if directivity is notrequired (e.g. close miking), the omni MK 2Swith windscreen W 5 or W 5 D will offer lowsensitivity to wind, ”popping” and handlingnoise. If high directivity is required outdoors, theMK 41 can be used with the W 5 D, W 20 R1or WSR MS ”basket”-type windscreens withbuilt-in elastic suspension for mono or stereo.
Attaching a Capsule or An ActiveAccessoryMK -- capsules are interchangeable and canbe screwed onto any CMC -- amplifier orActive Accessory (see System Overview, page 2).To avoid damaging the threads, please proceedas follows:
Place the capsule against the front end ofthe microphone amplifier.
Now turn the capsule first counter-clockwise(not pressing the parts together) until you feela gentle ”click”:
You are then at the beginning of the thread,and can attach the capsule or accessory to themicrophone amplifier with normal clockwiserotation:
(The engraved markings on the capsule maynot always line up as shown with those on theamplifier.)
If you are using an Active Accessory, attach it tothe microphone amplifier in a similar man ner.
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Capsule SelectionCa
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SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Basic Characteristics of TransducersCa
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10
Essentially flat, with perfect reproduc-tion of low frequencies. The on-axisresponse of the free-field capsule doesnot have a high-frequency emphasisbut the capsule meant for the rever-berant sound field does.
Omnidirectional pattern in its idealform at low and middle frequencies.At very high frequencies there isincreasing directivity. For this reasoneven omnidirectional microphones areaimed toward the sound source.
No proximity effect
Very little; simple foam-type wind-screens are usually sufficient.
Reduced sensitivity (rolloff) at lowerfrequencies, which can be compen-sated by close placement to thesound source (proximity effect)
Types: wide cardioid, Open Cardioid,cardioid, supercardioid (hypercardioid),bidirectional (figure-8). The frequencyresponse of our figure-8 is nearly thesame in all directions; the wide car-dioid capsule has this advantagealso.
Proximity effect: Elevation of the lowand low-mid frequencies as workingdistance decreases (quite noticeableat less than 50 cm)
Possibly considerable; shock mountsand more elaborate windscreens maybe necessary.
Characteristics of the Two Basic Transducer Types
All the wide variety of SCHOEPS capsules, without exception, are single-diaphragm electrostatic trans-ducers. They fall into two general categories: pressure transducers and pressure gradient transducers.Many of our capsules combine the two principles of operation in various proportions, yielding pat-terns from wide cardioid through supercardioid; these capsules are classed as pressure gradient trans-ducers by convention.
Unlike dual-membrane capsules, our switchable capsule offers flat low-frequency response, lowsensitivity to wind and solid-borne noise, and no proximity effect in its omnidirectional setting. In itscardioid setting it maintains its directional pattern to the lowest frequencies, which dual-diaphragmcapsules do not do.
The following table lists the basic characteristics of these two general types.
SCHOEPS ”Colette” Series capsules (MK --) can be used interchangeably on all CMC-series amplifiers.They can also be used with two special-purpose amplifier types: the CMBI (powered by internal battery,with unbalanced output) and the M 222 (modern, transformerless vacuum-tube circuitry). The oper-ating requirements and range of accessories for these amplifiers vary; for detailed information pleasesee the main catalog or www.schoeps.de.
Pressure Transducers (omnis) MK 2, 2H, 2S, 2XS,BLM 3, BLM 03C
MK 5 in the ”omni” position
Pressure Gradient TransducersMK 21, 21H, 22, 4, 4V, 41, 41V, 8MK 5 in the ”cardioid” position,
MK 4P, 4VP, 4XP, 4VXP
Frequencyresponse:
Directional pattern:
Near field behavior:
Sensitivity tovibration, windand popping:
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Suggested Capsules for Specific ApplicationsCa
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Appliations: Recommendations:
On a lectern MK 4 (cardioid) with B 5 D close-speech guardConference recording MK 4 (cardioid) with B 5 D close-speech guard;
for close pickup < 20 cm: cardioid with bass rolloff MK 4P; for close pickup < 10 cm: cardioid with bass rolloff MK 4XP
TV speaker’s table MK 4 (cardioid) without pop filter at a distance exceeding 40 cm Broadcast studio MK 4 with PR 120 SV pop filter; also SCHOEPS V4 UTV “round table” discussion MK 4 (cardioid) or boundary-layer capsule BLM 03 Cg (hemisphere);
also SCHOEPS BL CCM 3Church MK 4 (cardioid) or boundary-layer capsule BLM 03 C (hemisphere)Stage MK 4 (cardioid) or MK 41 (supercardioid) with BLCg, CMR microphone
amplifier and pocket transmitter Stage (movable) MK 4 (cardioid) or MK 41 (supercardioid) with CMR microphone
amplifier and pocket transmitter Stage (hand-held) CMH 64 (wire-bound) or wireless hand-held radio mircophone from
Wisycom or Audio Ltd. with SCHOEPS MK capsule Stage (fixed) MK 4 (cardioid) on an RC Active Tube with B 5 D windscreenNews reporting MK 5 (omni/ cardioid, switchable); use the omni setting if there is
strong wind and/ or when there is no disturbing ambient noise; wind-screens: B 5 D, W 5 D or W 20 R1
Film and video dialog/effects MK 41, possibly wireless with CMR, CUT 60, B 5 D, KC, GVC;also SCHOEPS CMIT/ SuperCMIT
Studio MK 4, MK 4V (cardioid), MK 22 (Open Cardioid) with PR 120 S/-SVpop filter; also SCHOEPS V4 U
All instr. incl. percussion MK 4 (cardioid); to pick up room sound as well – especialy with anorgan: MK 2S (omni) or – when the room’s character is less thanoptimal or if the bass is too strong: MK 21 (wide cardioid)
Tympani, bass drum, etc. pressure transducer, e.g. MK 2 (omni) Instruments with adapters violin: MK 4/ MK 4V (cardioid), saxophone: MK 4 (cardioid)Spot mike in an orchestra MK 4 (cardioid), MK 41 (supercardioid), but also MK 21 (wide cardioid)
or MK 22 (Open Cardioid), all with an RC Active Tube Orchestra, chorus ORTF microphone MSTC 64; A/B recording, e.g. with MK 2S , BLM 3g
or BLM 03 Cg; M/S with MK 4/ MK 21 (cardioid/ wide cardioid) andMK 8 (figure-8); Decca-Tree with 3× MK 2H, perhaps using KA 40accessory spheres
Small orchestra / ensemble M/S with RCY Active Tube or microphones of the COLETTE ModularSystem, boundary-layer technique, ORTF or X/Y with UMS 20 stereobracket
Film and video dialog/effects M/S with MK 41 (supercardioid) in the M-channel and MK 8 (figure-8)or with a CMIT and CCM 8, boundary-layer technique with BLM 03 Cg,e.g. under a thin table cloth or in a car under the top
Orchestra OCT surround; Decca Tree with 5× MK 2H, perhaps using KA 40accessory spheres; near-coincident placement with 5× MK 21 (widecardioid) or MK 4 (cardioid)/ MK 22 (Open Cardioid), HamasakiSquare with 4× MK 8 (figure-8)
Film and video dialog/effects Double M/S
Surr
ound
Ster
eoIn
stru
men
tsSp
eech
/ S
peak
ers
/ Vo
cals
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Pressure Transducers (Omnis)
Frequency response curve MK 2 + CMC 620 50 100 200 500 1k 2k 5k 10k 20kHz
Frequency response curve MK 2H + CMC 6 20 50 100 200 500 1k 2k 5k 10k 20kHz
Actual miking distances will dependgreatly on characteristics of therecording environment – especiallysize and reverberance – and on per-sonal preference.Each of these capsules, when usedat appropriate distance, will have awell-balanced overall response giventhe mixture of direct and reflectedsound energy typical of that distance.
Note: Since the capsules have somedirectionality at high frequencies, itis still necessary to aim them withrespect to the sound source, eventhough they are ”omnidirectional.”With the microphone amplifierCMC 6xt, the frequency range ofthese capsules can be extended to40 kHz.
+10
0dB
-10
-20
+10
0dB
-10
-20
*reverberation radius: the ”critical distance” from the sound source atwhich the levels of direct and diffuse sound are equal in a given space.
Frequency response curve MK 2S + CMC 620 50 100 200 500 1k 2k 5k 10k 20kHz
Frequency response curve MK 2XS + CMC 620 50 100 200 500 1k 2k 5k 10k 20kHz
+10
0dB
-10
-20
+10
0dB
-10
-20
MK 2 for free-field placement(close to the sound source)
MK 2H for use at moderate dis-tance (at or near thereverberation radius*)
MK 2S all-purpose capsule formusic and speech, alsofor use at moderate dis-tance (at or near thereverberation radius*)
MK 2XS for diffuse-field placement(distinctly beyond thereverberation radius*)
Polar diagram MK 2, -2H, -2S, -2XS
from outerto inner:
up to 1 kHz 4 kHz2 kHz 8 kHz
16 kHz
Caps
ules
12
MK 2 MK 2H
MK 2S MK 2XS
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Boundary-Layer Microphones Ca
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Frequency response curve BLM 3g, BLM 03Cg + CMC 6
Polar diagram BLM 3g, BLM 03Cg
from outerto inner:
up to 2 kHz 4 kHz8 kHz
16 kHz
20 50 100 200 500 1k 2k 5k 10k 20kHz
+10
0dB
-10
-20
– boundary-layer capsules– hemispheric directional pattern– no coloration of off-axis sound
Suggested applications: Music (orchestra, including pit orches-tra); on-stage; speech. BLM 03C: Round-table discussions
Note: The BLM capsules rely on the bound-ary-layer (”pressure zone”) effect.They will have the frequency responseshown here only when placed on afloor or another large, flat, rigid surfacewhich is not covered by thick carpetingor other sound-absorbent material. Forspeech applications such as conferencerecording, a table top may suffice.
BLM 03Cg
BLM 3g
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Wide Cardioids / Open Cardioid
14
Frequency response curve MK 21 + CMC 6
Polar diagram MK 21, -21H
from outerto inner:
up to 1 kHz 4 kHz2 kHz 8 kHz
16 kHz
+10
0dB
-10
-2020 50 100 200 500 1k 2k 5k 10k 20kHz
Frequency response curve MK 21H + CMC 6
+10
0dB
-10
-2020 50 100 200 500 1k 2k 5k 10k 20kHz
– wide cardioids– polar pattern very well maintained
throughout the frequency range– a favorable compromise between
omni (good low-frequency response)and cardioid (consistent directionalpattern at all frequencies)
Suggested applications:MK 21: music (orchestras), spot micro-
phone; vocals; speechMK 21H: wherever a high-frequency
elevation is desired, esp. non-classi-cal music
20 50 100 200 500 1k 2k 5k 10k 20kHz
Frequency response curve MK 22 + CMC 6
Polar diagram MK 22
von außennach innen:
bis 2kHz 4kHz8kHz
16kHz
+10
0dB
-10
-20
Caps
ules
MK 21 MK 21H
MK 22
– directional pattern: ”Open Cadioid”– optimal combination of classic car-
dioid directionality (MK 4) with thesonic character of the wide cardioid(MK 21)
– directional pattern largely constantthroughout the frequency range
Suggested applications:as spot / soloist’s microphone
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Cardioids
Frequency response curve MK 4V + CMC 6
Polar diagram MK 4V
from outerto inner:
up to 2 kHz 4 kHz8 kHz
16 kHz
+10
0dB
-10
-2020 50 100 200 500 1k 2k 5k 10k 20kHz
MK 4
– standard cardioid with clear soundquality, free of coloration
– all-purpose capsule for music andspeech
– our best-selling capsule type– 0° axis is at the tip of the capsule
MK 4V
– cardioid with mild high-frequencyboost
– all-purpose capsule for music andspeech
– highly consistent polar response– 0° axis is at the side of the capsule
marked by a red dot
Note:Though not specifically designed for such use, the MK 4V capsule can also beused on the RC Active Tube or the variable angle joint GVC; when fully tight-ened it will rarely be aimed where you intend. On request we will supply anelastic ring which can be slipped over the threads of the RC or GVC so thatthe final turn of the capsule will place it at the desired angle of rotation.This ring must be kept out of the capsule threads, however.
Caps
ules
15
Frequency response curve MK 4 + CMC 6
Polar diagram MK 4
from outerto inner:
up to 1 kHz 4 kHz2 kHz 8 kHz
16 kHz
20 50 100 200 500 1k 2k 5k 10k 20kHz
+10
0dB
-10
-20
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Supercardioids
Frequency response curve MK 41V + CMC 6
Polar diagram MK 41V
from outerto inner:
up to 2 kHz 4 kHz8 kHz
16 kHz
+10
0dB
-10
-2020 50 100 200 500 1k 2k 5k 10k 20kHz
Note:Though not specifically designed for such use, the MK 41V capsule can also beused on the RC Active Tube or the variable angle joint GVC; when fully tight-ened it will rarely be aimed where you intend. On request we will supply anelastic ring which can be slipped over the threads of the RC or GVC so thatthe final turn of the capsule will place it at the desired angle of rotation.This ring must be kept out of the capsule threads, however.
16
Frequency response curve MK 41 + CMC 6
Polar diagram MK 41
from outerto inner:
up to 1 kHz 4 kHz2 kHz 8 kHz
16 kHz
+10
0dB
-10
-2020 50 100 200 500 1k 2k 5k 10k 20kHz
Caps
ules MK 41
– all-purpose capsule for speech andmusic recording of all kinds
– well suited for use as the mainmicrophones for stereo pickupand/or as ”spot” microphones
– extended, smooth, well-balancedfrequency response
– often used for film and video sound – has distinct sonic and practical
advantages over most shotgunmicrophones
– highly consistent polar response – 0° axis is at the tip of the capsule
MK 41V
– all-purpose capsule for music andspeech; same uses and advantagesas the MK 41
– 0° axis is at the side of the capsulemarked by a red dot
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Figure-8 / Switchable Capsule
Frequency response curve MK 8 + CMC 6
Polar diagram MK 8
from outerto inner:
up to 2 kHz 4 kHz8 kHz
16 kHz
+10
0dB
-10
-2020 50 100 200 500 1k 2k 5k 10k 20kHz
17
Frequency response MK 5 ”omni” + CMC 6Polar diagram identical to that of MK 2, -2H, -2S, -2XS
+10
0dB
-10
-2020 50 100 200 500 1k 2k 5k 10k 20kHz
Frequency response MK 5 ”cardioid” + CMC 6
Polar diagram MK 5
from outerto inner:
up to 2 kHz 4 kHz8 kHz
16 kHz
+10
0dB
-10
-2020 50 100 200 500 1k 2k 5k 10k 20kHz
”cardioid” position
Caps
ules
MK 8
– figure-8 (”bidirectional”) pattern – clear sound quality, free of coloration– for M/S and Blumlein stereo– highly consistent frequency and
polar response – response essentially free of off-axis
peaks like a good ribbon microphone(but not as delicate physically)
– lateral pickup
MK 5
– mechanically switchable single-dia -phragm capsule (omni / cardioid)
– smoother, more extended high-fre-quency response than most othermulti-pattern microphones (e.g.dual-diaphragm capsules of othermanufacturers)
– a pure pressure transducer when inthe ”omni” setting (flat, extendedlow-frequency response withoutproximity effect or undue sensitivityto wind or solid-borne sound)
– slightly brighter than the MK 2H(omni) or MK 4 (cardioid)
Intermediate switch positions aremechanically possible, but are notreproducable or recommended.
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Cardioids for Close Pickup
When a directional microphone isused close to a sound source, its low-frequency response increases greatly.This ”proximity effect” gives voices anartificial ”boomy” quality which issometimes useful as a special effect,but it reduces intelligibility and causeslistener fatigue.
To avoid this problem and to reducethe effects of breath noise and pop-ping on consonants, low-frequencyfiltering can be applied (e.g. the CUT 60Active Filter) or special speech capsuleswith reduced low-frequency sensitivitycan be used. These same measuresalso help to suppress low-frequencyenvironmental noise.
Caps
ules
18
MK 4
MK 4(V)XP
MK 4(V)P
Low-frequency response curves of the two microphone types (P and XP) compared to the standard MK 4 (measured at a 60 cmequivalent distance).
Polar diagram MK 4P, MK 4XP
from outerto inner:
up to 1 kHz 4 kHz2 kHz 8 kHz
16 kHz
Polar diagram MK 4VP, MK 4VXP
from outerto inner:
up to 1 kHz 4 kHz2 kHz 8 kHz
16 kHz
MK 4VP
MK 4XP
MK 4P
MK 4VXP
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Cardioids for Close PickupCa
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Frequency response curve MK 4P
Frequency response curve MK 4VP
Frequency response curve MK 4XP
Frequency response curve MK 4VXP
MK 4VXP
– cardioid for lateralpickup
– for pick up of speechor music at closerange (under 10 cm)
– considerable attenua-tion of low frequencies
MK 4P
– cardioid pattern– for pickup of speech or
music at close range(under 20 cm)
– moderate attenuationof low frequencies
MK 4VP
– cardioid pattern, side-adressed
– for pickup of speech ormusic at close range(under 20 cm), other-wise the sound maybecome “thin“
– moderate low frequencyattenuation
MK 4XP
– cardioid pattern– for pickup of speech
or music at closerange (under 10cm)
– considerable attenua-tion of low frequencies
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
SpecificationsCa
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Capsule Type Polar Frequency Range Sensitivity Equivalent Noise Level Signal-to-Noise Max. SPLPattern CCIR A-weighted Ratio (0.5% THD)
A-weighted
MK 2 omni 20 Hz – 20 kHz* 15 mV/Pa 23 dB 11 dB 83 dB 130 dB
MK 2H omni 20 Hz – 20 kHz* 15 mV/Pa 23 dB 12 dB 82 dB 130 dB
MK 2S omni 20 Hz – 20 kHz* 12 mV/Pa 24 dB 12 dB 82 dB 132 dB
MK 2XS omni 20 Hz – 20 kHz* 10 mV/Pa 26 dB 14 dB 80 dB 134 dB
BLM 3g hemisphere 20 Hz – 20 kHz 19 mV/Pa 23 dB 12 dB 82 dB 128 dB
BLM 03 Cg hemisphere 20 Hz – 20 kHz 19 mV/Pa 23 dB 12 dB 82 dB 128 dB
MK 21 wide cardioid 30 Hz – 20 kHz* 13 mV/Pa 25 dB 15 dB 79 dB 132 dB
MK 21H wide cardioid 30 Hz – 20 kHz* 10 mV/Pa 26 dB 16 dB 78 dB 134 dB
MK 22 Open Cardioid 40 Hz – 20 kHz* 14mV/Pa 23 dB 14 dB 80 dB 131 dB
MK 4 cardioid 40 Hz – 20 kHz* 13 mV/Pa 24 dB 15 dB 79 dB 132 dB
MK 4V cardioid 40 Hz – 20 kHz 13 mV/Pa 24 dB 14 dB 80 dB 132 dB
MK 41 supercardioid 40 Hz – 20 kHz* 13 mV/Pa 24 dB 16 dB 78 dB 132 dB
MK 41V supercardioid 40 Hz – 20 kHz 13 mV/Pa 24 dB 15 dB 79 dB 132 dB
MK 8 figure-8 40 Hz – 16 kHz 10 mV/Pa 26 dB 18 dB 76 dB 134 dB
MK 5 omni 20 Hz – 20 kHz* 11 mV/Pa 26 dB 14 dB 80 dB 133 dB
cardioid 40 Hz – 20 kHz 13 mV/Pa 25 dB 16 dB 78 dB 132 dB
MK 4P cardioid close pickup 13 mV/Pa 24 dB 15 dB 79 dB 132 dB
MK 4VP cardioid close pickup 13 mV/Pa 24 dB 15 dB 79 dB 132 dB
MK 4XP cardioid close pickup 12 mV/Pa 25 dB 15 dB 79 B 132 dB
MK 4VXP cardioid close pickup 10 mV/Pa 25 dB 14 dB 80 dB 134 dB
Specifications for Complete Microphones: MK -- Capsules with CMC 6 Microphone Amplifier
* When the CMC 6 xt microphone amplifier is used with axially addressed capsules, the frequency response extendsbeyond 40 kHz.
A word about signal-to-noise specifications for studio micro-phones: The standard method, which we follow, is really justan alternate way of stating a microphone's equivalent noiselevel. It is designed to allow comparison of noise floor levelsfor different microphones. Unlike the signal-to-noise specifica-tions for other types of audio equipment, which give the ratioof a component's clipping point to its noise floor, these valuesdo not indicate a microphone's entire available dynamic range.Instead, the values are measured with reference to a standardsound pressure level of 1 Pascal (1 Pa = 94 dB SPL). But theactual maximum SPL capability of any usable microphone
exceeds that reference level substantially. The signal-to-noisespecifications of our microphones would be 35 to 40 dB (!)greater if the ”hi-fi” approach were used.
The use of ”A” weighting when specifying the equivalentnoise level of microphones is another often-misunderstoodaspect of the standards. ”A” weighting yields a distinctlylower noise specification – often by 10 dB or thereabouts –and this figure, of course, becomes the one most often citedin advertising. But the CCIR weighted noise level may well bea more accurate indicator of a microphone's perceived noiselevel in practice.
Care of Colette Series CondenserMicrophone Capsules
Please be careful to avoid placing capsules ina dusty environment. Keep them in their cases(or in the wood case of the microphone ampli-fier) when not in use, since any dust that getsinside the capsules can adversely affect theirfunctioning. In combination with humidity itcan lead to condensation and thus poppingand crackling noises (often described as ”fryingsounds”).
What to do if …the microphone is noisy (clicks and pops) in highhumidity?
– If the microphone is brought from the coldoutdoors into a warm environment, snappingor clicking noises can result from the con-densation of moisture. In such a case themicrophone should be given time to reachroom temperature, and as a rule it will thenperform flawlessly.
– Sometimes dirt can get into the contacts atthe end of the microphone amplifier or ofan Active Accessory where the capsule isattached; this, too, can cause impulse noise.You can clean the contacts yourself by usingcompressed air (without lubricant) from anaerosol can. If that doesn't help, you canscrub them with a new, clean toothbrushdipped in isopropyl alcohol, holding themicrophone amplifier or Active Accessoryso that the contacts face downward. Shakeoff any extra fluid; under no circumstancescan it be allowed to flow into the amplifier!Be careful to wipe the contacts dry.
If this treatment does not eliminate the noise,it is possible that dirt has gotten inside thecapsule itself – in which case the capsule mustbe sent back to the factory for cleaning. Westrongly urge customers not to open a cap-sule or attempt to clean it themselves. Doingso would also void all warranties. Neithershould the contact rings of a capsule becleaned with any kind of liquid. Windscreensare recommended when micro phones have to
be used in dirty or dusty environments in orderto avoid problems of the kind described above.
Possible Problems
Wind Noise and Polar PatternNoise problems may be a consideration whenchoosing a microphone pattern (directionalcharacteristic) for a given set of recording con-ditions. Pressure transducers are considerablyless prone than pressure gradient transducers(such as cardioids or supercardioids) to pickup noise from air currents or mechanicalvibra tion. SCHOEPS omnidirectional capsulesare pressure transducers, as are our switchable-pattern capsules in their omnidirectional set-tings. If strong wind is anticipated, or physicalvibration of the microphone, perhaps a pressuretransducer such as the MK 2S should be usedinstead of a cardioid or supercardioid. The dis-tance between the microphone and the soundsource should then be reduced by about halfif possible.
Wind Noise and WindscreensAir motion (wind, vocal ”popping” on sungor spoken consonants, motion of the micro-phone on a boom arm, or air currents due toheating or air conditioning systems) can causenoise that should always be dealt with. Even ifit doesn't cause overload, it will detract fromthe clarity of sound. A wind or pop screenshould be used, but should be chosen carefullyto avoid changing the microphone's character-istics too much. Many screen types which areeffective at reducing wind noise also have atendency to reduce a microphone's direction-ality and/or its high-frequency response. Basket-type windscreens are generally more effectivethan foam-type windscreens when directionalcapsules are being used, and their main sideeffect is to create some unevenness in frequencyresponse (see our main catalog for details).
VibrationIf noise from mechanical vibration enters astand- or boom-mounted microphone, a shockmount (elastic suspension) should be used, and
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Care and Maintenance / Possible ProblemsCa
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a loop of slack cable should be isolated andtied off so that it does not become anotherway for vibrations to reach the microphone.Unlike a wind screen, a shock mount will notaffect the characteristics of a microphone. Inmany kinds of work it is well justified to use ashock mount ”by default.”
OverloadWhen dealing with problems of overload, it isuseful to think of your recording equipmentas a series of circuit stages. The goal is to findthe first stage that is being overloaded, and toattenuate the signal at the input to that stage.Reducing the gain at any earlier stage wouldadd unnecessary noise, while reducing it at alater stage would not solve the problem.
A condenser microphone represents two cir-cuit stages: the capsule and the amplifier. Inpractice, capsules are rarely overloaded exceptby explosions or very strong wind; the onlysound pressure levels that could overload aSCHOEPS capsule are so extreme – ca. 150 dBSPL – that they would quickly damage humanhearing. Properly powered SCHOEPS CMCamplifiers can normally handle 130+ dB soundpressure levels, depending on the capsule type.Such levels rarely occur in unamplified sound,though their equivalents can be caused by windwhen directional capsules are used. In addition,proper powering should not be taken forgranted; insufficient or incorrect microphonepowering has proved to be the cause of manyotherwise mysterious “overload” problems.
If wind and powering can be excluded aspossible issues, however, overload is far morelikely to occur in the input circuitry of mixers,preamps or recorders than in SCHOEPS CMCseries microphones. This is true particularlywith consumer audio equipment, though eventoday some professional equipment is stilldesigned primarily for use with dynamic micro -phones or with earlier, less sensitive condensermicrophones. If an input sensitivity control isavailable, it should be set low enough to avoidinput overload, but not so low as to causeexcess noise – though a few dB of extra hiss ispreferable to the risk of hard clipping. Levelmeters and overload indicators don’t generally
detect input overload even in fully professionalequipment; they operate only at later stagesof the circuitry.
If overload occurs where powering, highsound pressure levels and wind are not theproblem and an input sensitivity control cannotbe turned down, the next logical step is toplug in a balanced resistive ”pad” (attenuator)such as the SCHOEPS MDZ 10 or MDZ 20 atthe preamp input. If the sound qualityimproves, leave the pad in place; as long as amicrophone isn’t being overloaded, it is alwaysbetter to pad the preamp input than themicrophone. Only if there are extreme soundpressure levels should a capacitive attenuator(SCHOEPS PAD 10 or PAD 20) be used.
Low-frequency disturbances such as windand solid-borne vibration may not be directlyaudible as such, but infrasonic noise can stillcause overload in some stage of the signalchain. A windscreen then becomes the firstline of defense. But low-frequency noise canalso be effectively suppressed in SCHOEPSColette microphones with the Active FilterCUT 60, inserted between the capsule andamplifier. This filter has the side effect of raisinga CMC amplifier’s gain to that of the +5 dBoption (see pages 4 and 5), but given theenormous levels of noise which can be gener-ated by wind, they are helpful far more oftenthan not. Alternatively, the simpler lowcut filtersLC 60 or LC 120 can be placed at the input ofa phantom-powered preamp.
Overload which does not otherwise seemto make sense may actually be a symptom ofincorrect or inadequate microphone powering.Powering systems and their requirements arediscussed near the beginning of this manualon page 5.
The least expensive, most helpful trouble -shooting tools are:
– a known good microphone cable– a simple pop screen such as the SCHOEPS
B 5 (or for outdoor recording, a windscreen such as the SCHOEPS W 5)
– a balanced, in-line resistive attenuator (”pad”)such as the SCHOEPS MDZ 10 or MDZ 20
– an ordinary multimeter
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Possible ProblemsCa
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Warranty
We guarantee our products for a period oftwenty-four months, except for batteries. The guarantee period begins on the date ofpurchase.
Please provide your bill of sale in all cases asproof of guarantee; without it, repairs will beundertaken only at the owner's expense. We reserve the right to satisfy all warrantyrequirements regarding defects of workman-ship or materials by means of repair or partialor complete replacement of the product, atour sole discretion.
Excluded from this guarantee are defects dueto misuse (e.g. incorrect operation; mechanicaldamage), abuse or “Acts of God.” This guar-antee is nullified in the event of tampering byunauthorized persons or agencies.
To secure your rights under this guarantee,send the product with proof of purchase anda precise description of the malfunction, at yourexpense, either to SCHOEPS (if you are a cus-tomer in Germany), or to our representative (if you are a customer outside of Germany).
Prior to sending your defective product forrepair, please contact your local dealer or dis-tributor for instructions. In exceptional casesyou can, by prior arrangement with SCHOEPS,send the product directly to us from a foreigncountry. However any return shipment mustthen be prepaid; this tends to cause delays,especially for non-warranty service. Full pay-ment must be made before a repaired itemcan be returned to the customer.
This guarantee does not affect any contractualagreements which may exist between the buyerand seller of the equipment.
This guarantee is world-wide.
Declaration of Conformity – CE-Mark
The CE-mark guarantees that all productsconform to relevant standards approved bythe European Community. The productsdescribed in this User Guide comply with cur-rent, relevant standards when used with cablesfrom SCHOEPS.
Relevant directives:EMC Directive 2014/30/EU
Relevant standards: EN 55 103-1, -2 and those which are referredto by them.
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Warranty / Declaration of ConformityCa
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Subject to change without notice.Not responsible for errors or omissions.
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SCHOEPS GmbHSpitalstrasse 20D-76227 Karlsruhe (Durlach)Germany
Tel: +49 721 943 20-0Fax: +49 721 943 2050