Download MKH 20...70

service manual
MKH 20...70
SA 050418
MKH 20
MKH 30
MKH 40
MKH 50
Subject to alterations
MKH 60
MKH 70
Sennheiser electronic GmbH & Co. KG • 30900 Wedemark
Phone: +49 (5130) 600 0 • Fax: +49 (5130) 600 300
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MKH 20...70
Safety requirements
Observe safety regulations.
Observe ESD instructions while handling electrostatically endangered components.
Only skilled persons are allowed to alter and repair. For repairs and exchanges only
approved components according to the current spare parts list ere allowed.
It is forbidden to alter the product unauthorized.
If not observed the adaptor is legally liable for possible results of damage.
repairs/exchanges
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The following instructions for overhaul and testing must be followed. In case of
unusual problems please contact your Sennheiser distributor.
MKH 20...70
04/2005
Contents
MKH 20...70....................................................................................... 2
Safety requirements ......................................................................................2
Description ......................................................................................................5
Test instructions.............................................................................................9
MKH 20 P 48.................................................................................... 11
Brief description .......................................................................................... 11
Features ........................................................................................................ 11
Controls......................................................................................................... 12
Technical data .............................................................................................. 12
Exploded view .............................................................................................. 14
Schematic representations ........................................................................ 15
MKH 20, solder side ......................................................................................................... 15
MKH 20, component side ............................................................................................... 15
MKH 20, circuit diagram ................................................................................................. 16
MKH 30 P 48.................................................................................... 17
Brief description .......................................................................................... 17
Features ........................................................................................................ 17
Controls......................................................................................................... 18
Technical Data.............................................................................................. 18
Exploded view .............................................................................................. 20
Schematic representations ........................................................................ 21
MKH 30, solder side ......................................................................................................... 21
MKH 30, component side ............................................................................................... 21
MKH 30, circuit diagram ................................................................................................. 22
MKH 40 P 48.................................................................................... 23
Brief description .......................................................................................... 23
Features ........................................................................................................ 23
Controls......................................................................................................... 24
Technical Data.............................................................................................. 24
Exploded view .............................................................................................. 26
Schematic representations ........................................................................ 27
MKH 40, solder side ......................................................................................................... 27
MKH 40, component side ............................................................................................... 27
MKH 40, circuit diagram ................................................................................................. 28
MKH 20...70
04/2005
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Contents
MKH 50 P 48 ................................................................................... 29
Brief description...........................................................................................29
Features.........................................................................................................29
Controls .........................................................................................................30
Technical Data ..............................................................................................30
Exploded view...............................................................................................32
Schematic representations.........................................................................33
MKH 50, solder side......................................................................................................... 33
MKH 50, component side ............................................................................................... 33
MKH 50, circuit diagram ................................................................................................. 34
MKH 60-1 P 48................................................................................ 35
Brief description...........................................................................................35
Features.........................................................................................................35
Controls .........................................................................................................36
Technical Data ..............................................................................................36
Exploded view...............................................................................................38
Schematic representations.........................................................................40
MKH 60, solder side......................................................................................................... 40
MKH 60, component side ............................................................................................... 40
MKH 60, circuit diagram ................................................................................................. 41
MKH 60, component side, new...................................................................................... 42
MKH 60, solder side, new ............................................................................................... 42
MKH 60, circuit diagram, new ....................................................................................... 43
MKH 70-1 P 48................................................................................ 45
Brief description...........................................................................................45
Features.........................................................................................................45
Controls .........................................................................................................46
Technical Data ..............................................................................................46
Exploded view...............................................................................................48
Schematic representations.........................................................................50
MKH 70, solder side......................................................................................................... 50
MKH 70, component side ............................................................................................... 50
MKH 70, circuit diagram ................................................................................................. 51
MKH 70, component side, new...................................................................................... 52
MKH 70, solder side, new ............................................................................................... 52
MKH 70, circuit diagram, new ....................................................................................... 53
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MKH 20...70
04/2005
Description
Contents of these Service Instructions
These Service Instructions summarize the technical documentation on the
microphones MKH 20 to MKH 70. Information concerning all models is given first,
followed by detailed data on individual microphones.
Service concept
Tests and checks for faults are divided into 3 parts:
1. Acoustic test
2. Capsule check
3. Test instructions
General service information
In the event of a service incident, perform a general functional check, first. For this
purpose, connect the microphone to an amplifier under field conditions and
monitor the microphone using headphones. Speak into the microphone, shake the
microphone, and move the connection cable.
In most cases, this acoustic test will give you a first impression of the kind of fault
that occurred. Perform all subsequent testing and measuring measures according
to the following test instructions.
Checking the microphone capsule
To check the microphone capsule, disassemble the microphone, first.
For the MKH 60 and the MKH 70, unscrew the sound inlet, first.
Loosen the two countersunk head screws on the housing and then use the XLR connector pins to carefully press out the frame together with the capsule. To further
disassemble the microphone, loosen the three screws on the capsule and then pull
off the capsule.
Before you touch the connections 1 and 3, touch the capsule housing to avoid
damage due to electrostatic discharge. When connecting measuring equipment,
always establish the connection to the capsule housing (pin 2) first.
Attention!
Checking the capacitance
Capsule connections (bottom view):
Use a capacitance meter to measure the capsule capacitance.
3
1
2
Type 1; KS 20, 30, 40, 50
Type 2; KS 60, 70
Capacitance: 40 to 45pF
Capacitance: 30 to 35pF
Checking the insulation
Capsule connections (bottom view):
Use a multimeter (20MΩ range) to measure the capsule resistance.
3
1
R>20MΩ (out of range)
2
MKH 20...70
04/2005
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Circuit description MKH20...70
RF bridge circuit (capsule bridge)
In connection with the windings 1-2 and 3-4 of the RF coil L1 the push-pull capsule
forms a bridge circuit. Each displacement of the diaphragm by a sound signal
changes the two capsule capacitances in the respective opposite direction,
resulting in a proportional RF voltage at the bridge output 2/3. L3 compensates the
reactive component of the bridge output impedance, so that the bridge output
becomes a real and low-resistance output.
Using the coil core of L1 the bridge is balanced by changing the winding
inductances in the respective opposite directions, so that the bridge output voltage
becomes zero when the diaphragm is in its neutral position. This is the case when
the direct voltage between the measuring points A and B becomes zero (balance).
The bridge output signal is transformed by the RF coil L2 and decoupled from
ground. Its primary winding 13-14 is roughly tuned to the oscillator frequency by
C1. A fine-tuning with the core of L2 is not required, since the circuit is highly
attenuated by the low bridge impedance. For optimum coupling, the core should be
positioned in the center of the coil.
Together with the tapping 16/17 of the secondary winding 15-18 the switch
makes it possible to achieve a signal attenuation of 10dB (pre-attenuation).
The demodulator and oscillator circuits of the microphones MKH20...50 and
MKH60...70 only differ with regard to different component references. In the
following sections, data that exclusively apply to the MKH60...70 are put in
parentheses.
Demodulator
Via L2 the RF bridge signal is supplied to the demodulator with D1, D2, and C5, C6
(or C3, C5) and the symmetrical windings 5-6 and 7-8 of L1. The demodulator
operates as a synchronous rectifier putting through the RF signal of L2 to C6 (or C5)
during one half-wave, while blocking it during the other half-wave. The rectified
voltage at C5 (or C3) biases both D1 and D2 to such an extent that they will securely
block even signals with a higher intensity. The rectified voltage is stabilized with
D3, D4 (or R6, R9).
When zero balancing is correct, the direct voltage between the measuring points A
and B reaches zero, and half the rectified voltage is supplied to C6 (or C5).
Depending on the direction of diaphragm displacement the bridge output voltage
is either in phase or opposite in phase to the voltages at the diode windings 5-8.
The synchronous rectification results in an increase or decrease of the voltage at C6
(or C5) corresponding to the diaphragm movement.
Oscillator
The frequency of the RF oscillator results from the capsule capacitances and the
inductances of the L1 windings 1-2 and 3-4 and ranges from about 6.5 to 7.5MHz.
The collector winding 9-10 and the feedback winding 11-12 couple the oscillator
transistor T1 (or Q1) to the capsule circuit. R1 prevents generation of parasitic oscillations in the VHF range. C2, C3, C4 (or C2, C4, C10) are used for RF blocking, L4
(or L5) acts as an RF choke.
The operating current of the microphone flows through the oscillator and is
stabilized to 2mA by T2 (or Q2), R3, R4, and R5 (constant-current circuit). The NTC
resistor R5 stabilizes against temperature influences. R2 ensures a sufficiently high
collector voltage of T2 (or Q2), since the base-emitter voltage of T1 (or Q1) is
negative (Class C mode).
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MKH 20...70
04/2005
AF amplifier MKH20...50
Since the AF circuits of the microphones MKH20...50 and MKH60...70 differ
considerably, they are described separately in the following sections.
The amplifier in the MKH20...50 operates with the complementary transistors T3
(or Q3) and T4 (or Q4) in push-pull Class A mode. On the DC side, the transistors are
connected in series, on the AC side they are connected in parallel via C12 and C14.
This increases the available AC output current, enhances the linearity, and reduces
the background noise. The base voltage divider R17, R18, R19, D5 determines the
operating voltage of the amplifier and stabilizes it against temperature influences.
The AF signal of the demodulator is supplied to the amplifier input via the high pass
C19, R16, and C11. The amplifier output is connected to the microphone output via
C15, C16, R22, R23, and the RF barrier L6, L7, and C17 to C20. The output impedance
is mainly determined by R22, R23, and the resistive portions of L6 and L7, and is
about 150Ω. The Z diodes D6 to D8 protect C14 to C16 from overvoltages.
For each microphone type, the frequency response of the capsule is equalized by
frequency-dependent negative-feedback circuits described for the individual types
in the following sections.
Equalization for MKH20
The series resonance circuit L5, C7, R7 in connection with R9 and R14 causes a treble
emphasis with a maximum at 20kHz. In the S2 standard position, R9 is
short-circuited and only R14 is effective. If S2 is opened (diffuse-field correction),
R9 is in series with R14 and causes a higher treble emphasis. R13 and C8 correct the
frequency response in the center frequency range.
Equalization for MKH30...50
The series resonance circuit L5, C7, R7 in connection with R9 causes a treble
emphasis with a maximum at 20kHz. In addition, C9, R11, and R12 cause a bass
emphasis. In the S2 standard position, R11 and R12 are connected in parallel. If S2
is opened (bass roll-off), only R12 is effective and the bass emphasis is reduced.
R13 and C8 correct the frequency response in the center frequency range.
AF amplifier MKH60...70
The amplifier integrated in both the MKH60 and the MKH70 is a two-stage
amplifier. The pre-amplifier with T3 (or Q3) equalizes the capsule frequency
response. The output stage operates as a high-pass filter at low frequencies.
The AF output signal of the demodulator is supplied to the base of T3 (or Q3) via
the high-pass of C6, C7 in connection with the base voltage divider R10, R11. S2 can
be used to switch the operating frequency of the bass roll-off.
Frequency response equalization for high frequencies is realized by the
negative-feedback network R9, R12, R13, C8, and L4. S3 can be used to switch the
operating frequency of the treble emphasis, so that the result is either a neutral
frequency response or a frequency response with treble emphasis.
The collector resistance of T3 (or Q3) results from the dynamic internal resistance
of the oscillator circuit and is very high in the AF range due to the current
stabilization.
The output signal of the pre-amplifier is supplied to the output stage via C12 and
C13. The output stage operates as an active high-pass with voltage amplification 1.
The quality is determined by a positive feedback via R14 in interaction with R15
and R17. T4 (or Q4) and T5 (or Q5) operate in complementary push-pull Class A
mode. On the DC side, they are connected in series, on the AC side, they are
connected in parallel via C14 and C16. This increases the available AC output
current, enhances the linearity, and reduces the background noise. The base
voltage divider R15, R16, R17, D3 determines the operating voltage and stabilizes
it against temperature influences.
MKH 20...70
04/2005
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The amplifier output signal is supplied to the microphone output via C17, C18, R20,
R21, and the RF barrier L6, L7, and C19 to C22. The output impedance is mainly
determined by R20, R21, and the resistive portions of L6 and L7, and is about 150Ω
in the center frequency range. The Z diodes D4 to D6 protect C16 to C18 from
overvoltages.
Output circuit
During phantom supply, each of the two cable strands supplies half of the
operating current to the microphone. The divided operating current is merged by
the two resistors R20 and R21 (or R18, R19) with identical resistances. The current
flows back to the phantom supply source via the amplifier circuit (MKH60...70: via
both amplifier stages), the oscillator, and the cable shield (microphone ground).
Since the operating current is stabilized by the oscillator circuit, the AC side of the
amplifier circuit is decoupled from ground ("electronic choke") and the available
output signal is floating. The signal is balanced by means of the two supply
resistors (6.8kΩ each) of the phantom supply source.
8/53
MKH 20...70
04/2005
Test instructions
Measuring and test equipment
1 AF generator, output voltage 1V
1 AF voltmeter, 10mV range
1 oscilloscope
1 handheld multimeter, range 2VDC
1 capacitance meter, 0 to 100pF
1 ohmmeter, range 20MΩ
1 headphones
Measuring set-up
oscilloscope
voltmeter
Device
under test
phantom
supply
48 V
headphones
amplifier
Test procedure
Circuit test MKH20/MKH30/MKH40/MKH50:
쐃 Operating voltage microphone:
Check voltages between R22 or R23 and ground; desired value = +41V;
both voltages have to be identical.
If the no-load voltage of the phantom supply device is not 48V, the deviation
from the desired value has to be identical.
쐇 Current consumption microphone:
Check voltages via R20 and R21; desired value in each case = 3.3V
(corresponds to a current of 1mA in each case);
both voltages have to be identical.
쐋 Balancing:
Check the voltage between the measuring points A(+) and B(-);
desired value = 0V
If the value is not 0V, rotate the coil core of L1 until the voltage is 0V.
쐏 Operating voltages output stage:
Check voltage via D6; desired value = 9V
Check voltage via D8; desired value = 8V
쐄 Operating voltage oscillator:
Check voltage via C4; desired value = +28.5V
MKH 20...70
04/2005
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Circuit test MKH60/MKH70:
쐃 Operating voltage microphone:
Check voltages between R20 or R21 and ground; desired value = +41V;
both voltages have to be identical.
If the no-load voltage of the phantom supply device is not 48V, the deviation
from the desired value has to be identical.
쐇 Current consumption microphone:
Check voltages via R18 and R19; desired value in each case = 2.2V
(corresponds to 1mA in each case);
both voltages have to be identical.
쐋 Balancing:
Check the voltage between the measuring points A(+) and B(-);
desired value = 0V
If the value is not 0V, rotate the coil core of L1 until the voltage is 0V.
쐏 Operating voltage output stage:
Check voltage via D4; desired value = 4.5V
Check voltage via D5; desired value = 4.5V
쐄 Operating voltage oscillator:
Check voltage via C10; desired value = +30.5V
10/53
MKH 20...70
04/2005
service manual
MKH 20 P 48
SA 050418
MKH 20 P 48
Brief description
The MKH 20 P 48 is a high-frequency condenser microphone with
omnidirectional characteristic.
Subject to alterations
Features
•
•
•
•
•
Very low noise for highly dynamical recordings
Distortion-free transmission of sound pressures of up to 142dB
Transmission range 20 to 20000Hz
Balanced transformer-free signal decoupling
Switchable diffuse-field correction for recordings outside of the
diffuse-field distance
• Switchable pre-attenuation
Sennheiser electronic GmbH & Co. KG • 30900 Wedemark
Phone: +49 (5130) 600 0 • Fax: +49 (5130) 600 300
11/53
Controls
diffuse-field correction
MKH 20 P 48
-10 dB
switch for 10dB sensitivity reduction
Technical data
Note
The values in parentheses apply to activated pre-attenuation (-10dB)
Acoustic principle _____________________
Directional characteristic _______________
Transmission range ___________________
Free-field no-load transmission factor
at 1kHz ____________________________
Equivalent sound pressure level
according to DIN 45500, curve A_____
according to DIN 45405/CCIR 468____
Max. sound pressure level ______________
Output _____________________________
Electrical impedance at 1kHz ____________
Min. terminating impedance ____________
Pre-attenuation ______________________
Diffuse-field correction_________________
Infrasonic attenuation _________________
Plug-in connection ____________________
Connector layout _____________________
Power supply ________________________
Supply voltage _______________________
Supply current _______________________
Dimensions (in mm)___________________
Weight _____________________________
Scope of delivery _____________________
12/53
Pressure receiver
omnidirectional
20 to 20000Hz
25mV/Pa (8mV/Pa)
= -32dBV (-42dBV)
10dB (18dB)
20dB (28dB)
134dB (142dB)
balanced, transformer-free
150Ω
1000Ω
10dB, switchable
switchable
18dB/oct below 20Hz
XLR3
1: -, housing
2: +, AF+
3: +, AFPhantom supply 48V
48V ±4V
2mA
25 ∅ x 150
approx. 100g
1 microphone MKH 20 P 48,
1 floorstand clamp MZQ 40,
1 close-talking and
wind protection MZW 41
MKH 20 P 48
04/2005
Frequency response
Wirkung der Diffusfeldkorrektur
diffuse-field correction activated
Polar diagram
MKH 20 P 48
04/2005
13/53
Exploded view
003
010
015
Pos
Designation
001
002
003
004
Easy release clamp
005
006
007
008
009
010
011
012
013
014
015
009
008
013 014
S001
012
S002
012
S001
S002
Thread insert
Damping ring
Countersunk screw
hexagon socket M2.5x4
Housing MKH20
Metal screw ST2.2x6.5
Connecting shell for XLR3
Chassis complete
Countersunk screw M2x3
Condenser capsule KS20
Type plate MKH20
Brace
IC mounting DIL6
Plate
O ring 18x1
(for condenser capsule version 2)
Slide switch
Slide switch
007
006
011
005
004
001
002
004
14/53
MKH 20 P 48
04/2005
MKH 20 P 48
04/2005
MKH 20, solder side
MKH 20, component side
3-6079-1L2
Schematic representations
15/53
MKH 20, circuit diagram
16/53
MKH 20 P 48
04/2005
service manual
MKH 30 P 48
SA 050418
MKH 30 P 48
Brief description
The MKH 30 P 48 is a high-frequency condenser microphone with
bidirectional characteristic.
Subject to alterations
Features
•
•
•
•
•
•
Very low noise for highly dynamical recordings
Distortion-free transmission of sound pressures of up to 142dB
Transmission range 40 to 20000Hz
Balanced transformer-free signal decoupling
Switchable roll-off filter
Switchable pre-attenuation
Sennheiser electronic GmbH & Co. KG • 30900 Wedemark
Phone: +49 (5130) 600 0 • Fax: +49 (5130) 600 300
17/53
Controls
roll-off filter
M K3
MKH
30
H0P 48
8
4
pre-attenuation (10dB)
Technical Data
The values in parentheses apply to activated pre-attenuation (-10dB)
Acoustic principle _____________________
Directional characteristic _______________
Transmission range ___________________
Free-field no-load transmission factor
at 1kHz ____________________________
Equivalent sound pressure level
according to DIN 45500, curve A_____
Equivalent sound pressure level
according to DIN 45405/CCIR 468____
Max. sound pressure level ______________
Output _____________________________
Electrical impedance at 1kHz ____________
Min. terminating impedance ____________
Pre-attenuation ______________________
Low-cut filter (cut-off) _________________
Roll-off filter ________________________
Plug-in connection ____________________
Connector layout _____________________
Power supply ________________________
Supply voltage _______________________
Supply current _______________________
Dimensions (in mm)___________________
Weight _____________________________
Scope of delivery _____________________
18/53
Pressure gradient receiver
bidirectional
40 to 20000Hz
25mV/Pa (8mV/Pa)
= -32dBV (-42dBV)
13dB (19dB)
22dB (28dB)
134dB (142dB)
balanced, transformer-free
150Ω
1000Ω
10dB, switchable
12dB/oct below 30Hz
additional 4dB reduction at 50Hz
XLR3
1: -, housing
2: +, AF+
3: +, AFPhantom supply 48V
48V ±4V
2mA
25 ∅ x 150
approx. 110g
1 microphone MKH 30 P 48,
1 floorstand clamp MZQ 40,
1 close-talking and
wind protection MZW 41
MKH 30 P 48
04/2005
Frequency response
Wirkung der schaltbaren Tiefendämpfung
bass roll-off activated
Polar diagram
MKH 30 P 48
04/2005
19/53
Exploded view
001
002
003
004
Pos
Designation
001
002
003
004
005
Sound inlet complete with gauze
Condenser capsule KS30
Thread ring
Housing MKH30
Countersunk screw
hexagon socket M2.5x4
Countersunk screw M2x3
Chassis complete
Brace
Connecting shell for XLR3
Metal screw ST2.2x6.5
Type plate MKH30
IC mounting DIL6
Plate
Easy release clamp
Thread insert
O ring 18x1
(for condenser capsule version 2)
Slide switch
Slide switch
006
007
008
009
010
011
012
013
014
015
016
S001
S002
005
006
007
012/
013
S001
008
014
S002
008
009
015
010
011
20/53
MKH 30 P 48
04/2005
MKH 30 P 48
04/2005
MKH 30, solder side
3-6079-1L2
MKH 30, component side
blue marking
Schematic representations
21/53
MKH 30, circuit diagram
22/53
MKH 30 P 48
04/2005
service manual
MKH 40 P 48
SA 050418
MKH 40 P 48
Brief description
The MKH 40 P48 is a high-frequency condenser microphone with cardioid
characteristic.
Subject to alterations
Features
•
•
•
•
•
•
Very low noise for highly dynamical recordings
Largely frequency-independent directional characteristic
Broad transmission range
Balanced transformer-free signal decoupling
Switchable roll-off filter
Switchable pre-attenuation
Sennheiser electronic GmbH & Co. KG • 30900 Wedemark
Phone: +49 (5130) 600 0 • Fax: +49 (5130) 600 300
23/53
Controls
roll-off filter
MKH 40 P 48
pre-attenuation (10dB)
Technical Data
The values in parentheses apply to activated pre-attenuation (-10dB)
Acoustic principle _____________________
Directional characteristic _______________
Transmission range ___________________
Free-field no-load transmission factor
at 1kHz ____________________________
Equivalent sound pressure level
according to DIN 45500, curve A_____
Equivalent sound pressure level
according to DIN 45405/CCIR 468____
Max. sound pressure level ______________
Output _____________________________
Electrical impedance at 1kHz ____________
Min. terminating impedance ____________
Pre-attenuation ______________________
Low-cut filter (cut-off) _________________
Roll-off filter ________________________
Plug-in connection ____________________
Connector layout _____________________
Power supply ________________________
Supply voltage _______________________
Supply current _______________________
Dimensions (in mm)___________________
Weight _____________________________
Scope of delivery _____________________
24/53
Pressure gradient receiver
cardioid
40 to 20000Hz
25mV/Pa (8mV/Pa)
= -32dBV (-42dBV)
12dB (16dB)
21dB (26dB)
134dB (142dB)
balanced, transformer-free
150Ω
1000Ω
10dB, switchable
12dB/oct below 30Hz
additional 4dB reduction at 50Hz
XLR3
1: -, housing
2: +, AF+
3: +, AFPhantom supply 48V
48V ±4V
2mA
25 ∅ x 150
approx. 110g
1 microphone MKH 40 P 48,
1 floorstand clamp MZQ 40,
1 close-talking and
wind protection MZW 41
MKH 40 P 48
04/2005
Frequency response
Wirkung der schaltbaren Tiefendämpfung
bass roll-off activated
Polar diagram
MKH 40 P 48
04/2005
25/53
Exploded view
012
017
011
010
015 /
016
S001
014
014
S002
Pos
Designation
001
002
004
Easy release clamp
Thread insert
Countersunk screw
hexagon socket M2.5x4
Housing MKH40
Damping silk
Type plate MKH40
Metal screw ST2.2x6.5
Connecting shell for XLR3
Chassis complete
Countersunk screw M2x3
Condenser capsule KS40
Brace
IC mounting DIL6
Plate
O ring 18x1
Slide switch
Slide switch
005
006
007
008
009
010
011
012
014
015
016
017
S001
S002
009
008
007
006
005
004
001
002
26/53
MKH 40 P 48
04/2005
MKH 40 P 48
04/2005
MKH 40, solder side
3-6079-1L2
MKH 40, component side
red marking
Schematic representations
27/53
MKH 40, circuit diagram
28/53
MKH 40 P 48
04/2005
service manual
MKH 50 P 48
SA 050418
MKH 50 P 48
Brief description
The MKH 50 P 48 is a high-frequency condenser microphone with
hyper-cardioid characteristic.
Subject to alterations
Features
•
•
•
•
•
•
Very low noise for highly dynamical recordings
Largely frequency-independent directional characteristic
Broad transmission range
Balanced transformer-free signal decoupling
Switchable roll-off filter
Switchable pre-attenuation
Sennheiser electronic GmbH & Co. KG • 30900 Wedemark
Phone: +49 (5130) 600 0 • Fax: +49 (5130) 600 300
29/53
Controls
roll-off filter
pre-attenuation (10dB)
Technical Data
The values in parentheses apply to activated pre-attenuation (-10dB)
Acoustic principle _____________________
Directional characteristic _______________
Transmission range ___________________
Free-field no-load transmission factor
at 1kHz ____________________________
Equivalent sound pressure level
according to DIN 45500, curve A_____
Equivalent sound pressure level
according to DIN 45405/CCIR 468____
Max. sound pressure level at 1kHz ________
Output _____________________________
Electrical impedance at 1kHz ____________
Min. terminating impedance ____________
Pre-attenuation ______________________
Low-cut filter (cut-off) _________________
Roll-off filter ________________________
Plug-in connection ____________________
Connector layout _____________________
Power supply ________________________
Supply voltage _______________________
Supply current _______________________
Dimensions (in mm)___________________
Weight _____________________________
Scope of delivery _____________________
30/53
Pressure gradient receiver
hyper-cardioid
40 to 20000Hz
25mV/Pa (8mV/Pa)
= -32dBV (-42dBV)
12dB (18dB)
21dB (27dB)
134dB (142dB)
balanced, transformer-free
150Ω
1000Ω
10dB, switchable
12dB/oct below 30Hz
additional 4dB reduction at 50Hz
XLR3
1: -, housing
2: +, AF+
3: +, AFPhantom supply 48V
48V ±4V
2mA
25 ∅ x 150
approx. 100g
1 microphone MKH 50 P 48,
1 floorstand clamp MZQ 40,
1 close-talking and
wind protection MZW 41
MKH 50 P 48
04/2005
Frequency response
Equalization
Polar diagram
MKH 50 P 48
04/2005
31/53
Exploded view
001
002
018
Designation
001
002
003
004
005
006
007
Sound inlet complete with gauze
Condenser capsule KS50
Thread ring
Damping silk
Dust protection
Housing MKH50
Countersunk screw
hexagon socket M2.5x4
Countersunk screw M2x3
Chassis complete
Brace
Connecting shell for XLR3
Metal screw ST2.2x6.5
Type plate MKH50
IC mounting DIL6
Plate
Easy release clamp
Threaded insert
O ring 18x1
(for condenser capsule version 2)
Slide switch
Slide switch
003
004
005
006
Pos
008
009
010
011
012
013
014
015
016
017
018
S001
S002
007
008
009
014/
015
010 S001
S002
010
011
016
017
012
013
32/53
MKH 50 P 48
04/2005
MKH 50 P 48
04/2005
MKH 50, solder side
3-6079-1L2
MKH 50, component side
yellow marking
Schematic representations
33/53
MKH 50, circuit diagram
34/53
MKH 50 P 48
04/2005
service manual
MKH 60-1 P 48
SA 050418
MKH 60-1 P 48
Brief description
The MKH 60-1 P 48 is a high-frequency condenser microphone with
hyper-cardioid/lobe characteristic.
Subject to alterations
Features
•
•
•
•
•
Low noise for highly dynamical recordings
Uniform directional characteristic
Broad transmission range
Switchable pre-attenuation (-10dB)
Switchable filters (roll-off and presence)
Sennheiser electronic GmbH & Co. KG • 30900 Wedemark
Phone: +49 (5130) 600 0 • Fax: +49 (5130) 600 300
35/53
Controls
roll-off filter
presence filter
switch for 10dB sensitivity reduction
Technical Data
The values in parentheses apply to activated pre-attenuation (-10dB)
Acoustic principle _____________________ Pressure gradient/
interference receiver
Directional characteristic _______________ hyper-cardioid/lobe
Transmission range ___________________ 50 to 20000Hz
Free-field no-load transmission factor
at 1kHz ____________________________ 40mV/Pa (12.5mV/Pa)
Equivalent sound pressure level
according to DIN 45500, curve A_____ 9dB (16dB)
Equivalent sound pressure level
according to DIN 45405/CCIR 468____ 20dB (27dB)
Max. sound pressure level at 1kHz ________ 125dB (135dB)
Output _____________________________ balanced, transformer-free
Electrical impedance at 1kHz ____________ 150Ω
Min. terminating impedance ____________ 1000Ω
Pre-attenuation ______________________ 10dB, switchable
Low-cut filter (cut-off) _________________ 18dB/oct below 50Hz
Roll-off filter ________________________ additional 3dB reduction at 70Hz
Presence filter _______________________ 5dB emphasis at 10kHz
Plug-in connection ____________________ XLR3
Connector layout _____________________ 1: -, housing
2: +, AF+
3: +, AFPower supply ________________________ Phantom supply 48V
Supply voltage _______________________ 48V ±4V
Supply current _______________________ 2mA
Dimensions (in mm)___________________ 25 ∅ x 285
Weight _____________________________ approx. 150g
Scope of delivery _____________________ 1 microphone MKH 60-1 P 48
36/53
MKH 60-1 P 48
04/2005
Frequency response
Equalization
Polar diagram
MKH 60-1 P 48
04/2005
37/53
Exploded view
001
002
013
003
005
024
023
016
004
018
015
019
006
022
014
007
017
S002
S001 S003
020
018
008
010
011
38/53
MKH 60-1 P 48
04/2005
Pos
Designation
001
002
003
004
005
006
007
008
009
010
011
012
013
014
015
016
017
018
019
020
021
022
023
024
S001
S002
S003
Sound inlet MKH60/70
Ring
Gauze tube MKH60
Countersunk screw M1.4x3
Tube complete
Condenser capsule KS60
Countersunk screw M2x3
Chassis with PCB MKH60-1
Brace
Connecting shell for XLR3
Cheese head screw M2x5
Type plate MKH60-1
Housing MKH60
Countersunk screw hexagon socket M2.5x4
O ring 18x1
PCB assembly MKH60
Base for IC
Cheese head screw M1.7x3
Ring
Sheet metal 16.8x11.4
Type plate (frequency as order)
Socket contact with rubber ring
Cover 103.4x19.5x3.6
Cheese head screw M1.7x6
Slide switch
Slide switch
Slide switch
MKH 60-1 P 48
04/2005
39/53
40/53
MKH 60, solder side
MKH 60, component side
Schematic representations
MKH 60-1 P 48
04/2005
MKH 60, circuit diagram
MKH 60-1 P 48
04/2005
41/53
TP2
L3
R21
R20
+
D6
R19
C15
57820 L
R18
MKH 60, solder side, new
BF1
C20
C19
+
D5
+
MKH 60, component side, new
TP21
TP6
TP1
TP20
+
TP14
+
Q5
L1
TP10
TP9
TP13
R10
Q4
L2
L5
Q3
R11
TP16
TP18
TP15
R9
TP4
R17
TP22
C3
R12
TP19
R14
D4
C9
D8
R13
C11
S1
S2
S3
D2
C6
R6
TP5
D3
TP23
C8
BF2
C10
D1
L4
C14
C13
+
+
C4
C16
+
R1
Q1
TP11
C1
57820 B
D7
R2
Time
Time
Date
:
:
:
R5
L7
21.02.2005
14:42
C22
C21
L6
15.02.2005
09:46
R4
+
C18
:
+
C17
Date
C2
TP12
Q2
R16
TP8
R3
42/53
MKH 60-1 P 48
04/2005
R8
C12
C7
R7
C5
R15
2
BU
3
1
L3
TP4
rs
rs
L1
TP5
TP10
gn(sw)
gn
S1
2
TP12
TP11
3
2
BAS70-04
D2
3
BAT85
D8
TP16
A(+)
TP22
Q1
BC846B
TP13
R2
332RF
R1
68.1RF
L2
TP18
C2
10nK
1
22u16VTs
C3
D7
BAT85
-10dB
Secme-26581
TP8
TP9
rs(sw)
rs
rt
gn TP6
rt(sw)
gn(sw)
MKH 60, circuit diagram, new
100pJ
C1
5.6uK
rs(rt)
V TP19
24V HF
TP2
TP20
rs(sw)
Stift2
2 sw
Stift1
1 bl
TP1
H TP21
Stift3
3 rt
Ansicht von
hinten
KS 70
1
rt
*
*
gn(sw)
1,1V HF
+1,3V
16V HF
+29V
TP14
TP15
TP23
C7
+0,55V
R5
NTC
1.5KK
S2
Q2
BC850B
R8
475KF
Secme-26581
R4
332RF
C4
10nK
15nJ
*
C6
33nJ
*
+0,75V
B(-)
R3
332RF
C5
470pJ
15KF
R7
15KF
R6
S3
Secme-26581
R9
39.2RF
*
C8
68nJ
L4
1.0mJ
R12
R13
39uK
L5
1.21KF
+30,5V
R11
56.2KF
R10
15KF
1.21KF
C10
1.0nJ
C9
10nK
C
*
MKH60
MKH70
22u6V3Ts
C14
BC846B
BC850B
BC860B
MMBT5087
E
B
1.0u25VTs
C13
3.32KF
R14
*
R6,R7
6k81
15k
C15
10nK
+39V
HF-Spannungen gemessen mit Instrument Ci=1pF
6.8V
C18
D6
2.21KF
R18
47u10VTs
C17
9.1V
D5
D4
9.1V
2.21KF
R19
68u6V3Ts
C16
47u10VTs
+41V
+41V
1.0nJ
C20
39uK
L7
1.0nJ
Stift2
+41V
Stift3
+41V
C22
1.0nK
C21
1.0nK
MKH 60/70
68.1RF
R21
39uK
68.1RF
C19
L6
R20
030305kre0900
C6 C7 C12
68n 22n 330n
33n 15n 220n
Q5
BC850B
+36,5V
R9
R14
22R1 2k21
39R2 3k32
R17
33.2KF
D3
LL4148
R16
22.1KF
Q4
Gleichspannungen gemessen mit Instrument Ri=22MOhm
Q3,Q4: BC860B(Code 4F) or MMBT5087(Code 2Q)
C11
1.0nJ
220nJ
C12
*
Q3
MMBT5087LT1
R15
33.2KF
+34,5V
MMBT5087LT1
D1
BAS70-04
rs
24V HF
Stecker
XLR 3
3
MKH60 +8V
MKH70 +9,5V
rt(sw)
gn
rs(sw)
2
1
MKH 60-1 P 48
04/2005
43/53
Geh
44/53
MKH 60-1 P 48
04/2005
service manual
MKH 70-1 P 48
SA 050418
MKH 70-1 P 48
Brief description
The MKH 70-1 P 48 is a high-frequency condenser microphone with
hyper-cardioid/lobe characteristic.
Subject to alteration
Features
•
•
•
•
•
Low noise for highly dynamical recordings
Uniform directional characteristic
Broad transmission range
Switchable pre-attenuation (-10dB)
Switchable filters (roll-off and presence)
Sennheiser electronic GmbH & Co. KG • 30900 Wedemark
Phone: +49 (5130) 600 0 • Fax: +49 (5130) 600 300
45/53
Controls
roll-off filter
presence filter
switch for 10dB sensitivity reduction
Technical Data
The values in parentheses apply to activated pre-attenuation (-10dB)
Acoustic principle _____________________ Pressure gradient/
______________________________ interference receiver
Directional characteristic _______________ hyper-cardioid/lobe
Transmission range ___________________ 50 to 20000Hz
Free-field no-load transmission factor at 1kHz50mV/Pa (15mV/Pa)
______________________________ = -28dBV (-38dBV)
Equivalent sound pressure level
according to DIN 45500, curve A
8dB (15dB)
Equivalent sound pressure level
according to DIN 45405/CCIR 468____ 20dB (26dB)
Overload sound pressure level at 1kHz_____ 123dB (133dB)
Output _____________________________ balanced, transformer-free
Electrical impedance at 1kHz ____________ 150Ω
Min. terminating impedance ____________ 1000Ω
Pre-attenuation ______________________ 10dB, switchable
Low-cut filter (cut-off) _________________ 18dB/oct below 50Hz
Roll-off filter ________________________ additional 3dB reduction at 70Hz
Presence filter _______________________ 5dB emphasis at 10kHz
Plug-in connection ____________________ XLR3
Connector layout _____________________ 1: -, housing
2: +, AF+
3: +, AFPower supply ________________________ Phantom supply 48V
Supply voltage _______________________ 48V ±4V
Supply current _______________________ 2mA
Dimensions (in mm)___________________ 25 ∅ x 410
Weight _____________________________ approx. 180g
Scope of delivery _____________________ 1 microphone MKH 70-1 P 48
46/53
MKH 70-1 P 48
04/2005
Frequency response
Equalization
Polar diagram
MKH 70-1 P 48
04/2005
47/53
Exploded view
001
002
003
013
005
006
024
023
016
004
018
015
019
022
007
017
S002
S001 S003
020
014
018
010
011
48/53
008
MKH 70-1 P 48
04/2005
Pos
Designation
001
002
003
004
005
006
007
008
009
010
011
012
013
014
015
016
017
018
019
020
021
022
023
024
S001
S002
S003
Sound inlet MKH60/70
Ring
Gauze tube MKH70
Countersunk screw M1.4x3 DIN 963
Tube complete
Condenser capsule complete with gauze tube
Countersunk screw M2x3
Chassis with PCB MKH70-1
Brace
Connecting shell for XLR3
Cheese head screw M2x5
Type plate MKH70-1
Housing MKH70
Countersunk screw hexagon socket M2.5x4
O ring 18x1
Printed circuit board assy MKH70
Base for IC
Cheese head screw M1.7x3
Ring
Sheet metal 16.8x11.4
Type plate (frequency as order)
Socket contact with rubber ring
Cover 103.4x19.5x3.6
Cheese head screw M1.7x6
Slide switch
Slide switch
Slide switch
MKH 70-1 P 48
04/2005
49/53
TP2
TP6
TP1
L3
R21
R20
D6
C15
57820 L
R18
R19
MKH 70, solder side
BF1
C20
C19
D5
MKH 70, component side
TP21
L1
TP14
TP10
TP13
Q5
TP20
R17
TP4
R14
D4
Q4
R10
L5
L2
Q3
C9
TP19
R11
C3
TP18
TP15
TP16
R9
TP9
D8
R12
TP22
R13
C11
S1
S2
S3
D2
C6
R6
TP11
D3
TP23
C8
BF2
C12
C10
D1
L4
C14
C13
C4
C16
R1
Q1
TP5
D7
C1
TP12
C18
C17
Q2
57820 B
R2
R5
R3
R4
L6
C21
C22
R15
50/53
L7
TP8
Schematic representations
MKH 70-1 P 48
04/2005
C2
R8
C7
R7
C5
R16
MKH 70-1 P 48
04/2005
51/53
TP12
TP11
TP9
TP10
TP13
TP18
TP8
TP6
TP2
TP4
TP5
TP1
MKH 70, circuit diagram
TP19
TP20
TP21
TP16
TP14
TP15
TP2
L3
R21
R20
+
D6
R19
C15
57820 L
R18
MKH 70, solder side, new
BF1
C20
C19
+
D5
+
MKH 70, component side, new
TP21
TP6
TP1
TP20
+
TP14
+
Q5
L1
TP10
TP9
TP13
R10
Q4
L2
L5
Q3
R11
TP16
TP18
TP15
R9
TP4
R17
TP22
C3
R12
TP19
R14
D4
C9
D8
R13
C11
S1
S2
S3
D2
C6
R6
TP5
D3
TP23
C8
BF2
C10
D1
L4
C14
C13
+
+
C4
C16
+
R1
Q1
TP11
C1
57820 B
D7
R2
Time
Time
Date
:
:
:
R5
L7
21.02.2005
14:42
C22
C21
L6
15.02.2005
09:46
R4
+
C18
:
+
C17
Date
C2
TP12
Q2
R16
TP8
R3
52/53
MKH 70-1 P 48
04/2005
R8
C12
C7
R7
C5
R15
2
BU
3
1
L3
TP4
rs
rs
L1
TP5
TP10
gn(sw)
gn
S1
2
TP12
TP11
3
2
BAS70-04
D2
3
BAT85
D8
TP16
A(+)
TP22
Q1
BC846B
TP13
R2
332RF
R1
68.1RF
L2
TP18
C2
10nK
1
22u16VTs
C3
D7
BAT85
-10dB
Secme-26581
TP8
TP9
rs(sw)
rs
rt
gn TP6
rt(sw)
gn(sw)
MKH 70, circuit diagram, new
100pJ
C1
5.6uK
rs(rt)
V TP19
24V HF
TP2
TP20
rs(sw)
Stift2
2 sw
Stift1
1 bl
TP1
H TP21
Stift3
3 rt
Ansicht von
hinten
KS 70
1
rt
*
*
gn(sw)
1,1V HF
+1,3V
16V HF
+29V
TP14
TP15
TP23
C7
+0,55V
R5
NTC
1.5KK
S2
Q2
BC850B
R8
475KF
Secme-26581
R4
332RF
C4
10nK
15nJ
*
C6
33nJ
*
+0,75V
B(-)
R3
332RF
C5
470pJ
15KF
R7
15KF
R6
S3
Secme-26581
R9
39.2RF
*
C8
68nJ
L4
1.0mJ
R12
R13
39uK
L5
1.21KF
+30,5V
R11
56.2KF
R10
15KF
1.21KF
C10
1.0nJ
C9
10nK
C
*
MKH60
MKH70
22u6V3Ts
C14
BC846B
BC850B
BC860B
MMBT5087
E
B
1.0u25VTs
C13
3.32KF
R14
*
R6,R7
6k81
15k
C15
10nK
+39V
HF-Spannungen gemessen mit Instrument Ci=1pF
6.8V
C18
D6
2.21KF
R18
47u10VTs
C17
9.1V
D5
D4
9.1V
2.21KF
R19
68u6V3Ts
C16
47u10VTs
+41V
+41V
1.0nJ
C20
39uK
L7
1.0nJ
Stift2
+41V
Stift3
+41V
C22
1.0nK
C21
1.0nK
MKH 60/70
68.1RF
R21
39uK
68.1RF
C19
L6
R20
030305kre0900
C6 C7 C12
68n 22n 330n
33n 15n 220n
Q5
BC850B
+36,5V
R9
R14
22R1 2k21
39R2 3k32
R17
33.2KF
D3
LL4148
R16
22.1KF
Q4
Gleichspannungen gemessen mit Instrument Ri=22MOhm
Q3,Q4: BC860B(Code 4F) or MMBT5087(Code 2Q)
C11
1.0nJ
220nJ
C12
*
Q3
MMBT5087LT1
R15
33.2KF
+34,5V
MMBT5087LT1
D1
BAS70-04
rs
24V HF
Stecker
XLR 3
3
MKH60 +8V
MKH70 +9,5V
rt(sw)
gn
rs(sw)
2
1
MKH 70-1 P 48
04/2005
53
53/53
Geh