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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 21Care and Maintenance 22Possible Problems 22Warranty 24
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
...20 capsulesin all
RC KCActive Tube
(special version)
MK DZC GVC
KCActive Cable
CUT
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. VMS 5 Umicrophone preamplifierwith M/S matrix
MDZ 10,MDZ 20
CMC 4, T12
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 concert
amplification, recording and broadcasting.The active circuitry in these accessories convertsthe audio signal to lower impedance directlyat the capsule, so that there is no loss of soundquality:
In the following pages you will find technicalinformation, 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 (such as the SCHOEPSVMS 5U shown on page 2) or recorder thathas suitable microphone powering built in.Otherwise, a stand-alone microphone powersupply of proper type can be used.
Standard VersionsFour standard models of CMC amplifier areoffered to fit the specific type(s) of microphone
MK-- CMC--
+
+ +
Active Accessories
powering which the user expects to encounter.Variants of these types are also available, offer-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 the
CMC 6 has a 12 dB/octave rolloff below 20 Hzas a protection against infrasonics, while thestan 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.
In the realm of film and video sound anolder system called ”parallel powering” or ”T”powering (”Ton ader spei sung”) at 12 ± 1 Voltsis sometimes still used, particularly with Nagratape recorders; the CMC 4 amplifier modelworks with that system. See Fig. 3, p. 6 for aschematic diagram; since this method of pow-ering has been in decline for some time now,it is not described in detail in this manual.Please contact your SCHOEPS dealer or SCHOEPSGmbH with any questions concerning its use.
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 somewhat
GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Types of Microphone AmplifiersM
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greater. 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 vibrationand 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 cautionis advised with respect to infrasonics. Sincepressure 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 asopposed 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 should
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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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 pinsof the microphone must still connect to itsphantom or parallel power supply.
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* see note in the text concerning tolerances
with XLR-5 (stereo microphones)
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-3connector
XLR-3-connector
cable
Ohms
Ohms
* recommended values:C: 100μF, 63V; R: 22kΩ, 1%
** Tolerance ca. 5%; precisematching is not critical.
Fig. 3 Parallel powering;
with parallel powering there is low-impedance
DC across pins 2 and 3. This can damage
dynamic microphones, especially ribbons. z.B. 10 kOhm
**
**
R*
be 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.
Unbalanced OperationUnbalanced operation of CMC microphoneamplifiers is not recommended; both noise andvulnerability to interference will be increased.
shield
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 HzCMC 4U: 12 V parallel 9 mA 13 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)
electromagnetic 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: 1) Keep both the microphone and the cable
away 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 of
the microphone cable should connect tochassis ground in the shortest way possible.If necessary, this coupling can be capacitive.
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 longerthe 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 and
7
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Block Diagram of the CMC 3, 5, 6 Microphone AmplifiersM
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8
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
+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
thre
e si
mpl
e m
etho
ds f
or v
erify
ing
corr
ect
phan
tom
pow
erin
g.Th
ese
mea
sure
men
ts s
houl
d be
mad
e at
an
unus
ed in
put.
Red
uce
the
chan
nel g
ain
to p
rote
ct lo
udsp
eake
rs,
etc.
If m
icro
phon
es a
re c
onne
cted
to o
ther
inpu
ts a
t th
e sa
me
time,
no
subs
tant
ial d
iffer
ence
sho
uld
occu
rin
the
res
ults
.1.
Mea
sure
the
ope
n-ci
rcui
t vo
ltage
bet
wee
n gr
ound
(pi
n 1)
and
eith
erpi
n 2
or p
in 3
of
the
XLR
inpu
t. G
iven
the
per
mitt
ed t
oler
ance
s, t
his
volta
ge s
houl
d be
bet
wee
n 44
and
52
VD
C f
or P
48,
and
betw
een
11an
d 13
VD
C f
or P
12.
Then
, m
easu
re t
he s
hort
-circ
uit
curr
ent
betw
een
grou
nd (
pin
1) a
nd e
ither
pin
2 o
r pi
n 3
of t
he X
LR in
put.
Giv
en t
he p
er-
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.
scre
en
-pha
se
+ph
ase
XLR
-3co
nnec
tor
XLR
-3co
nnec
tor
Pin
1:sc
reen
(G
ND
)Pi
n 2:
+ph
ase
Pin
3:–p
hase
Bott
om v
iew
(a
s th
e pi
ns a
re s
een)
12
3
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-V
olt
supp
ly,
they
sho
uld
be a
bout
34
Vol
ts (
min
i-m
um =
30
Vol
ts).
For
P12
this
is 8
.3 V
olts
(m
inim
um 7
.3 V
olts
) w
ith a
CM
C 3
, an
d 9
Vol
ts (
min
imum
8 V
olts
) w
ith a
CM
C 6
.3)
For
P48
, use
a S
CHOE
PSPH
S 48
tes
ter.
Plug
it in
to
the
XLR
inpu
t so
cket
;if
the
LED
glo
ws
and
stay
s lit
, all
is w
ell.
Nom
inal
vol
tage
gai
n: s
tan-
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 4S or MK 4VXS. 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 3.
– 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 itto the 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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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 (hypercar-dioid), bidirectional (figure-8). Thefrequency response of our figure-8 isnearly the same in all directions; thewide cardioid capsule has this advan-tage also.
Proximity effect: Elevation of the lowand low-mid frequencies as workingdistance decreases (quite noticeableat less than 50 cm)
Possibly considerable; shock mountsand more elaborate windscreensmay be 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 gradienttransducers 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 three special-purpose amplifier types: the CMBI (powered by internal bat-tery, with unbalanced output), the VST 62 IU (two-channel, balanced, phantom-powered) and the M 222(modern, transformerless vacuum-tube circuitry). The operating requirements and range of accessoriesfor these amplifiers vary; for detailed information please see the main catalog or www.schoeps.de.
Pressure Transducers (omnis) MK 2, 2H, 2S, 3,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 4S, 40, 4A, 4VXS, 41S
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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Applications: Recommendations:
On a lectern MK 4 (cardioid) with close-speech guard B 5 DConference recording MK 4 (cardioid) with close-speech guard B 5 DTV speaker’s table MK 4 (cardioid), no popscreen required at distances greater than
0.5 mRadio announcer MK 4V (cardioid with lateral pickup) with pop filter PR 120 SVNoisy environments (super-)cardioid for close pickup (10 – 20 cm) with bass rolloff:
MK 4S, MK 40, MK 41STV “round table” discussion MK 4 (cardioid) or boundary layer capsule BLM 03 Cg (hemisphere)Church MK 40 (cardioid) (perhaps as boundary layer microphone with BLC),
or BLM 03 CStage radio microphone type HXiR (AUDIO Ltd.) with MK 4 (cardioid) and
B 5 D popscreen or MK 2S (omni)News reporting MK 5 (omni / cardioid, switchable) with windscreen B 5 D or W 5 D
or W 20 R1 (use the omni setting if there is strong wind)Stage (movable) radio microphone HXiR (AUDIO Ltd.) with MK 4 (cardioid) or MK 2S
(omni) and popscreen B 5 DStage (fixed) MK 4 (cardioid) on RC Active Tube with windscreen B 5 D, vocalist
microphone CMH 64 (cardioid)Studio MK 4, MK 4V (cardioids), MK 22 (Open Cardioid) with pop filter
PR 120 S, PR 120 SVAll instr. incl. percussion: MK 4 (cardioid); to pick up room sound as well:especially for organ: MK 2S (omni); especially when the room’s character is less than opti-
mal or if the bass is too strong: MK 21 (wide cardioid) or MK 4(cardioid)
Tympani, bass drum, etc. pressure transducers, e.g. MK 2Instruments with adapters flute: MK 8 (figure-8), violin: MK 4V (cardioid), saxophone: MK 4
or MK 4V (cardioids)Accent miking (spot mike) in the orchestra: MK 4 (cardioid), MK 41 (supercardioid), but also
MK 21 (wide cardioid) or MK 22 (Open Cardioid)Orchestra, chorus ORTF microphone MSTC 64; for best low-frequency reproduction,
A/B recording e.g. with MK 2S or with BLM 3g or BLM 03 Cg;Decca Tree with 3× MK 2S, perhaps using KA 50 accessory spheres
Small orchestra / ensemble M/S with RCY Active Tube, boundary layer microphone or modularmicrophones, X/Y
Film and video dialog/effects M/S with MK 41 (supercardioid) in the M-channel or X/Y on aboom, boundary layer with BLM 03 Cg e.g. under a thin table-cloth or in a car under the top
Orchestra OCT surround; Decca Tree with 3× MK 2S, perhaps using KA 50accessory spheres
Film and video dialog/effects Double M/S on a boom and possibly a Hamasaki Square for increased envelopment Su
rrou
ndSt
ereo
Inst
rum
ents
Voc
als
Spee
ch /
Spe
aker
s
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 3 + 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 3 for diffuse-field placement(distinctly beyond thereverberation radius*)
MK 3MK 2S
MK 2 MK 2H
Polar diagram MK 2, -2H, -2S, -3
from outerto inner:
up to 1 kHz 4 kHz2 kHz 8 kHz
16 kHz
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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]
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 3g
BLM 03Cg
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 CardioidCa
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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
MK 21 MK 21H
MK 22
– new kind of 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
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
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 dotNote: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 fullytightened it will rarely be aimed where you intend. On request we will supplyan elastic ring which can be slipped over the threads of the RC or GVC sothat the 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.
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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
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
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 fullytightened it will rarely be aimed where you intend. On request we will supplyan elastic ring which can be slipped over the threads of the RC or GVC sothat the 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.
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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
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
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
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.
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Frequency response MK 5 ”omni” + CMC 6Polar diagram identical to that of MK 2, -2H, -2S, -3
+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
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
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
Frequency response curve MK 4S + CMC 6 Polar diagram identical to that of the MK 4
+10
0dB
-10
-2020 50 100 200 500 1k 2k 5k 10k 20kHz
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 1Active Filter) or special speech capsuleswith reduced low-frequency sensitivitycan be used. These same measuresalso help to suppress low-frequencyenvironmental noise.
MK 4S– for close pickup (ca. 50 cm = 20")
MK 40– for close pickup (ca. 50 cm = 20")– high-frequency emphasis for better
speech intelligibility in reveberantvenues (e.g. churches)
MK 4VXS– for extremely close pickup (under
10 cm = less than 4")– lateral pickup
MK 40MK 4SCaps
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MK 4VXS
Frequency response curve MK 40 + CMC 6
Polar diagram MK 40
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
20 50 100 200 500 1k
+10
0dB
-10
-20
MK 4 standardcardioid
MK 4S and MK 40
MK 4AMK 4VXS
Frequency response curve MK 4VXS + CMC 6Polar diagram essentially identical to that of the MK 4V
+10
0dB
-10
-2020 50 100 200 500 1k 2k 5k 10k 20kHz
The frequency response curves shown on these pages were ob tainedat the usual one-meter equivalent measuring distance. They showlow-frequency rolloffs which will suppress low-frequency en viron -mental noise. When these capsules are used at the indicated workingdistances, proximity effect and the low-frequency rolloff will bal-ance each other out, creating a natural-sounding pickup of the voice.
Low-frequencyattenuation ofcardioids forclose pickup
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
Cardioids / Supercardioid for Close Pickup
Frequency response curve MK 41S + CMC 6
Polar diagram MK 41S
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 41S
– supercardioid for close pickup(under 50 cm)
– considerable low-frequency attenuation
– compensates for proximity effect– suggested application: speech in a
loud environment
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MK 4A
– for extremely close pickup (under10 cm = less than 4")
– deliberate 10 dB reduction in sensitivity
– especially well suited for hand-heldradio microphones made by AUDIOLtd. (England)
Polar diagram MK 40
from outerto inner:
up to 1 kHz 4 kHz2 kHz 8 kHz
16 kHz
Frequency response curve MK 4A + CMC 6
+10
0dB
-10
-2020 50 100 200 500 1k 2k 5k 10k 20kHz
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 3 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 4S cardioid 80 Hz – 20 kHz 13 mV/Pa 24 dB 15 dB 79 dB 132 dB
MK 40 cardioid 80 Hz – 20 kHz 18 mV/Pa 22 dB 13 dB 81 dB 129 dB
MK 4A cardioid close pickup 3 mV/Pa 29 dB 18 dB 76 dB 144 dB
MK 4VXS cardioid close pickup 10 mV/Pa 24 dB 14 dB 80 dB 134 dB
MK 41S supercardioid 80 Hz – 20 kHz 13 mV/Pa 24 dB 15 dB 79 dB 132 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 warrantees. 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 2 S 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 CMC-series 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 can-not be turned down, the next logical step isto plug in a balanced resistive ”pad” (attenu-ator) such as the SCHOEPS MDZ 10 or MDZ 20at the 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 the micro-phone. Only if there are extreme sound pres-sure levels should a capacitive attenuator(SCHOEPS DZC 10 or DZC 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 FiltersCUT 1 or CUT 2, inserted between the capsuleand amplifier. These filters have the side effectof raising a CMC amplifier’s gain to that of the+5 dB option (see pages 4 and 5), but giventhe enormous levels of noise which can begenerated by wind, they are helpful far moreoften than not. Alternatively, the simpler low-cut filters LC 60 or LC 120 can be placed atthe input of a 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 or the SCHOEPSPHS 48 phantom power tester
SCHOEPS GmbH · Spitalstr. 20 · D-76227 Karlsruhe (Durlach) · Tel: +49 721 943 20-0 · Fax: +49 721 943 2050www.schoeps.de · [email protected]
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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: 89/336/EEC, amended by
92/31/EEC and 93/68/EEC
Relevant standards: EN 55 103-1, -2 and those which are referred
to 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]
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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