MEMS MICROPHONES
ECMs
SPECIALTY MICROPHONES
SPECIALTY SPEAKERS
CUSTOM ASSEMBLIES
ACOUSTIC SOFTWARE
MICROPHONE AND SPEAKER BASICS
Acoustic Interface Design Guide
2www.knowles.com
Discover
Knowles Acoustics offers you a full
spectrum of MEMS microphones,
electret condenser microphones,
specialty microphones, balanced
armature speakers, custom
assemblies, and sound conditioning
software. This application guide will
help you select the right acoustic
interface solution.
your next acoustic interface solution.
Knowles reserves the right to change designs and specifications without prior notice. Should a safety concern
arise regarding this product, please contact us immediately for technical consultation. Knowles cannot assume
responsibility for any problems arising out of the use of this product. This information does not convey any
license by any implication under any patents or other right.
3www.knowles.com
We can help you
every step of the way.
It all starts with your application. Or it starts with an idea you may
have. For support from concept to design to sub-assembly, or any step
along the way, just call us. Or visit us at www.knowles.com
MICROPHONES - MEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
MICROPHONES - ECMs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8
SPECIALTY TRANSDUCERS - MICROPHONES . . . . . . . . . . . . . . . . 9-14
ACCELEROMETERS & DAMPERS . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
SPECIALTY TRANSDUCERS - SPEAKERS . . . . . . . . . . . . . . . . . . 15-23
CUSTOM ASSEMBLIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
ACOUSTIC SOFTWARE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
MICROPHONE AND SPEAKER BASICS . . . . . . . . . . . . . . . . . . . . 26-27
Table of Contents
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MICROPHONES – MEMS
•New digital mics eliminate analog noise
•New integrated designs with differential or switchable gain
•Zero Height Mic
™
for thinnest ever designs
•Original "mini" with footprint less than 18mm2
•RF Hardened products eliminate GSM/TDMA burst noise
in handset designs
SiSonic™MEMS Microphones
The SiSonic™MEMS microphone series is entering its fourth generation of development, with product
shipments exceeding 400 million units to date. The proven and evolving design series continues to
support high-performance, high-density innovation in such applications as cell phones, digital still
cameras, portable music players, premium earbuds and other portable electronic devices.
Design variables include ever-smaller sizes, lower profiles and mounting options, increased output
capacities, and new digital audio options that eliminate analog noise. For manufacturers, surface
mount designs eliminate off-line subassembly production costs. Customized designs are supplied on
tape-and-reel and can be run through standard automatic pick-n-place equipment during in-line
surface mount manufacturing.
The microphones can also be integrated with our patented IntelliSonic™software and special porting designs to provide
a precisely customized sound.
Part Numbering
SPM0204HE3-PB-6
1 2 3 4 5 6 7
1
Product Description
SPU: Ultra (3.76x2.95)
SPM: Mini (4.72x3.76)
2
Series
0204: Standard
0205: Digital
0206: Differential
0207: Switchable
0208: Amplified
0408: Amplified
0409: Standard
3
Port Hole Type
H: Standard
L:ZHS
4
RF Filter
D: Standard
E: Enhanced
5
Supply Voltage
3: 1.5-5.5V
5: 1.5-3.6V
6
Version
Knowles Internal
Reference Only
7
Packaging QTY
(7” or 13” Reel)
2: 1200
3: 4500
6: 4800
T: 300 (7" Only)
MMooddeellDescription Directivity Supply Voltage Sensitivity @1kHz Output Maximum
(min-max) Frequency Range (dB re1V/1Pa) Impedance Current
(Ohms) Drain (mA)
SPM0204UD5 UAS Omni 1.5 to 3.6v 10k-65k Hz -47.0 < 300 < 0.25
•High frequency functionality
•Wide range of applications
•Micro-sized sensing and actuation
Ultrasonic Acoustic Sensor
Derived from our industry-leading MEMS silicon surface mount microphone technology,
our new ultrasonic sensor designs function on a high frequency band. Sensor designs
are possible across a wide spectrum of applications requiring highly miniaturized
solutions for sensing and actuation/signaling.
NOMINAL SENSITIVITY 0 = -47dBv/Pa
FREQUENCY (Hz)
30
20
10
0
-10
-20
-30
60k10k 20k 30k 40k 50k
MICROPHONES – MEMS
MMooddeellDescription Directivity Supply Voltage Sensitivity @1kHz Output Maximum
(min-max) RF Filtering (dB re1V/1Pa) Impedance Current
(Ohms) Drain (mA)
SPU0409HE5 Standard Omni 1.5 to 3.6v Enhanced -42.0 < 300 < 0.25
SPU0409HD5 Standard Omni 1.5 to 3.6v Standard -42.0 < 300 < 0.25
SPU0409HE5 Amplified Omni 1.5 to 3.6v Enhanced -22.0 < 300 < 0.35
SPU0409HD5 Amplified Omni 1.5 to 3.6v Standard -22.0 < 300 < 0.35
Zero Height Mic™Thin Mini Package - 4.72 x 3.76 x 1.25 (mm)
5
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Note: All performance curves are typical
STANDARD MOUNT ZERO HEIGHT MIC™
•New Ultra Mini with footprint of 11mm2
•Flexible designs available with/without RF filtering
and built in amplifier
•Ideal for miniature consumer electronics
•SiSonic Zero Height Mic™shrinks product thickness by up to 30%
•Minimizes distance between PCB and mobile device housing
•Ideal for microphone placement on reverse side of PCB, while maintaining acoustic port on top side of mobile device, for clamshell phone designs
•Enables the thinnest, highest density product designs
SENSITIVITY IN dB RELATIVE TO 1.0V/0.1 Pa
FREQUENCY (Hz)
SENSITIVITY IN dB RELATIVE TO 1.0V/0.1 Pa
FREQUENCY (Hz)
Ultra Mini Package - 3.76 x 2.95 x 1.10 (mm)
MMooddeellDescription Directivity Supply Voltage Sensitivity @1kHz Output Maximum
(min-max) RF Filtering (dB re1V/1Pa) Impedance Current
(Ohms) Drain (mA)
SPM0204LE5 Standard Omni 1.5 to 3.6v Enhanced -38.0 < 300 < 0.25
SPM0208LE5 Amplified Omni 1.5 to 3.6v Enhanced -18.0 < 300 < 0.35
10
5
0
-5
-10 2 3 4 5 6 7 8 9 2 3 4 5 6 7
1k 8k100
20
10
0
-10
-20
-30
1k 10k100
Thin Mini Package - 4.72 x 3.76 x 1.25 (mm)
•Thin Mini SiSonic with a footprint less than 18mm2reduces
manufacturing costs and brings greater design flexibility
•Rugged, solid-state design process for stable acoustic
performance under extreme conditions such as temperature,
shock and vibration
•Digital - Pulse Density Modulation (PDM) device available,
which has an integrated sleep mode and is compatible with
stereo input applications
SENSITIVITY IN dB RELATIVE TO 1.0V/0.1 Pa
FREQUENCY (Hz)
MMooddeellDescription Directivity Supply Voltage Sensitivity @1kHz Output Maximum
(min-max) RF Filtering (dB re1V/1Pa) Impedance Current
(Ohms) Drain (mA)
SPM0204HE5 Standard Omni 1.5 to 3.6v Enhanced -42.0 < 300 < 0.25
SPM0204HD5 Standard Omni 1.5 to 3.6v Standard -42.0 < 300 < 0.25
SPM0208HE5 Amplified Omni 1.5 to 3.6v Enhanced -22.0 < 300 < 0.35
SPM0208HD5 Amplified Omni 1.5 to 3.6v Standard -22.0 < 300 < 0.35
SPM0205HD4 Digital Omni 1.6 to 3.6v Standard -26.0 (1 Pa ref Full Scale) < 300 < 0.50
20
5
0
-5
-10
1k 8k100 2 3 4 5 6 7 8 9 2 3 4 5 6 7
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
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MICROPHONES – ECMs
Electret Condenser Microphones
Electret Condenser Microphones (ECM) are for general use in all electronic products requiring
a microphone. ECMs provide good acoustic performance and reliability under non-severe
environmental conditions.
Part Number System and Ordering Information
MB3015ASC-1
1 - ECM Sensitivity Level
C - Capacitor Configuration: A=10pF, B=33pF, C=33&10pF, Z=None
S - Terminal connection: B=PCB, P=Pin, S=Solder
A - Directivity: A=Omnidirectional, U=Uni-Directional, N=Noise Canceling, P=Preamplified
15 - Height of Microphone in mm (1.5)
30 - Diameter of Microphone in mm (3.0)
B - Charged Backplate, D=Charged Diaphram
M - Electret Type Microphone
•Highly efficient electrical specifications
•Industry standard sizes
•Omni, Uni, and Noise Canceling Directivities
•Integrated capacitors for RF filtering
•Multiple terminations - Solderless, Pin Type, and Solder Pad
•Used in a wide variety of applications, including wired and wireless headsets,
corded and cordless phones, PDAs, notebooks, and mobile phones
Omni-Directional – 3 mm
Size (mm) Part Number Sensitivity (db) Filter Termination
3x1.5 MB3015ASC-1 -42.0±3 10pF & 33pF Solder Type
MB3015ASC-2 -44.0±3 10pF & 33pF Solder Type
Notes:
1. All sensitives are referenced at 1 kHz (1V/Pa)
2. Frequency graphs are typical. Contact manufacturer
for more detailed information.
Omni-Directional – 4 mm
Size (mm) Part Number Sensitivity (db) Filter Termination
4x1.5 MB4015ASC-1L -42.0±3 10pF & 33pF Solder Type
4x1.5 FREQUENCY RESPONSE
RELATIVE SENSITIVITY (dB)
FREQUENCY (Hz)
20
10
0
-10
-20
-30 2 3 4 5 6 7 8 9
1k 10k
100
2 3 4 5 6 7 8 9
RELATIVE SENSITIVITY (dB)
100
-30
-20
20
-10
0
10
3x1.5 FREQUENCY RESPONSE
RELATIVE SENSITIVITY (dB)
FREQUENCY (Hz)
20
10
0
-10
-20
-30 2 3 4 5 6 7 8 9
1k 10k
100
2 3 4 5 6 7 8 9
7
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MICROPHONES – ECMs
Omni-Directional – 6 mm
Size (mm) Part Number Sensitivity (db) Filter Termination
6X1.3 MB6013ASC-1 -42.0±3 10pF & 33pF Solder Type
6x1.5 MB6015ASC-1 -42.0±3 10pF & 33pF Solder Type
6x2.2 MB6022ASC-1L -40.0±3 10pF & 33pF Solder Type
MB6022APC-0 -40.0±3 10pF & 33pF Pin Type
MB6022ABC-3 -45.0±2 10pF & 33pF PCB, Bullseye
6x2.7 MB6027ASC-1L -42.0±3 10pF & 33pF Solder Type
6X5.2 MB6052ASC-1 -42.0±3 10pF & 33pF Solder Type
6x1.3 FREQUENCY RESPONSE
Notes:
1. All sensitives are referenced at 1 kHz (1V/Pa)
2. Frequency graphs are typical. Contact manufacturer
for more detailed information.
6x1.5 FREQUENCY RESPONSE
6x2.2 FREQUENCY RESPONSE 6x2.7 FREQUENCY RESPONSE
RELATIVE SENSITIVITY (dB)
FREQUENCY (Hz)
RELATIVE SENSITIVITY (dB)
FREQUENCY (Hz)
RELATIVE SENSITIVITY (dB)
FREQUENCY (Hz)
RELATIVE SENSITIVITY (dB)
FREQUENCY (Hz)
Omni-Directional – 9.7 mm
Size (mm) Part Number Sensitivity (db) Filter Termination
9.7x4.5 MD9745APA-1 -41.0±3 10pF Pin Type
MD9745APZ-F -42.0±2 None Pin Type
9.7x4.5 FREQUENCY RESPONSE
RELATIVE SENSITIVITY (dB)
FREQUENCY (Hz)
20
10
0
-10
-20
-30
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
100 1k 10k
20
10
0
-10
-20
-30
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
100 1k 10k
20
10
0
-10
-20
-30
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
100 1k 10k
20
10
0
-10
-20
-30 2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
100 1k 10k
20
10
0
-10
-20
-30 2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
100 1k 10k
Far-Field
Near-Field
Far-Field
Near-Field
MICROPHONES – ECMs
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Uni-Directional – 3 mm, 6 mm, 9.7 mm
Size (mm) Part Number Sensitivity (db) Filter Termination
3x1.5 MB3015USB-3 -47.0±3 33pF Solder Type
MB3015USB-4 -49.0±3 33pF Solder Type
6x2.2 MB6022USC-3 -47.0±3 10pF & 33pF Solder Type
MB6022USC-3P -47.0±3 10pF & 33pF Solder Type
6x2.7 MB6027USC-3 -47.0±3 10pF & 33pF Solder Type
6x5.2 MB6052USZ-2 -44.0±3 None Solder Type
9.7x5 MB9750USB-4 -47.0±4 33pF Solder Type
Noise Canceling – 4 mm, 6 mm, 9.7 mm
Size (mm) Part Number Sensitivity (db) Filter Termination
4x1.5 MB4015NSC-3 -46.0±3 10pF & 33pF Solder Type
6x2.2 MB6022NSC-2 -44.0±3 10pF & 33pF Solder Type
9.7x5.2 MD9752NSZ-1 -40.0±3 None Solder Type
Knowles Acoustics has over 60 years experience with precision assembly for demanding applications. By allowing Knowles to
work with your design engineers we are typically able to provide a lower overall cost (time to market, R&D expenses,
production scrap and inventory issues) with some of the highest quality standards in the industry.
• Multiple value added models with cable wire leads and connectors along with rubber boot housings that all meet current RoHS standards are available
• Outsource your existing assembly that contains a Knowles component, and maintain control of drawings and process
• Meet Halogen Free and GREEN standards
9.7x5.2 FREQUENCY RESPONSE6x2.2 FREQUENCY RESPONSE
Notes:
1. All sensitives are referenced at 1 kHz (1V/Pa)
2. Frequency graphs are typical. Contact manufacturer
for more detailed information.
RELATIVE SENSITIVITY (dB)
FREQUENCY (Hz)
RELATIVE SENSITIVITY (dB)
FREQUENCY (Hz)
Value Added Microphone Assemblies
180˚
0˚
9.7x5.0 FREQUENCY RESPONSE
RELATIVE SENSITIVITY (dB)
FREQUENCY (Hz)
Far 50cm
Near 6mm
4x1.5 FREQUENCY RESPONSE
RELATIVE SENSITIVITY (dB)
FREQUENCY (Hz)
20
10
0
-10
-20
-30 2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
100 1k 10k
20
10
0
-10
-20
-30
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
100 1k 10k
10
0
-10
-20
-30
-40
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
100 1k 10k
10
0
-10
-20
-30
-40
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
100 1k 10k
0
180˚
0˚
6x2.2, 6x2.7, 6x5.2 FREQUENCY RESPONSE
RELATIVE SENSITIVITY (dB)
FREQUENCY (Hz)
20
10
0
-10
-20
-30 2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
100 1k 10k
0˚
180˚
0
0
3x1.5 FREQUENCY RESPONSE
RELATIVE SENSITIVITY (dB)
FREQUENCY (Hz)
20
10
0
-10
-20
-30 2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
100 1k 10k
FG SERIES
– Microphone
Omnidirectional 2.565 DIA x 2.565 (mm)
The FG Series microphone is the world’s smallest electret condenser microphone.
Its cylindrical shape and compact size facilitate compact designs. The FG can
also be used in directional applications as a matched omni-directional pair.
EM SERIES
– Microphone
Omnidirectional 3.63 x 3.63 x 2.28 (mm)
The EM is a popular, alternative omni-directional microphone. The EM can also
be used in directional applications as a matched omni-directional pair.
•Smallest microphone option
•High resistance to mechanical shock
•Exceptionally low vibration sensitivity
•Various responses available
•Integral RFI suppression
SPECIALTY TRANSDUCERS – Microphones
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Note: All performance curves are typical
The Specialty Transducer (ST) product line consists of miniature microphones, speakers, and
assemblies. Hundreds of design possibilities can be applied to your product challenge with our
high-performance microphone designs. Ideal for new product ideas that require premium audio
and very small form factors, solutions include noise canceling, omni-directional and unidirectional
performance. Other variables include size, shape, amplification, sensitivity, low noise, and resistance
to vibration and mechanical shock.
ST components and assemblies are unique in fit, form and function. Our products are designed
into high value applications in markets such as the following:
•Communications – headsets, handsets, earpieces, telephony, voice recognition, emergency services, military, surveillance
•Pro audio – in-ear speakers, lapel microphones, boom microphones
•Medical and more – sensors, audiometers, medical implants
SENSITIVITY IN dB RELATIVE TO 1.0V/0.1 Pa
FREQUENCY (Hz)
•High resistance to mechanical shock
•Improved RFI and EMI
•Undamped, screen damped, and internally damped responses
•Numerous port locations
•Wide range of frequency responses
SENSITIVITY IN dB RELATIVE TO 1.0V/0.1 Pa
FREQUENCY (Hz)
MMooddeellSensitivity @1kHz DC Supply (Vdc) Max. Amplifier Max. “A” Weighted Nominal Output
(dB re1V/1Pa) Current Drain (uA) Noise (1 kHz Impedance (Ohms) Comments
Equivalent SPL)
FG-23329-C05 -33.0±3 0.9-1.6 50 30.0 dB 4400 RFI Improved Version
FG-23329-P07 -33.0±3 0.9-1.6 50 30.0 dB 4400 3-wire, 1015 mm Shielded Cable
FG-23629-P16 -33.0±3 0.9-1.6 50 28.0 dB 4400 3-wire, 25.4 mm Litz Wires
FG-23629-C36 -33.0±3 0.9-1.6 50 28.0 dB 4400 RFI Improved Version
FG-23652-C36 -33.0±3 0.9-1.6 50 28.0 dB 4400 RFI Improved Version
FG-23652-P16 -33.0±3 0.9-1.6 50 28.0 dB 4400 3-wire, 25.4 mm Litz Wires
FG-23742-D36 -43.0±3 0.9-1.6 50 30.0 dB 4400 3-wire, 25.4 mm Litz Wires
FG-23742-P16 -43.0±3 0.9-1.6 50 36.0 dB 4400 3-wire, 25.4 mm Litz Wires
FG-26163-000 -33.0±3 0.9-1.6 50 93.0 dB 4400 RFI Improved Version
-40
-50
-60
-70
-80 2 3 4 5 6 7 8 9
100 1k 10k
2 3 4 5 6 7 8 9
-40
-50
-60
-70
-80
2 3 4 5 6 7 8 9
100 1k 10k
2 3 4 5 6 7 8 9
MMooddeellSensitivity @1kHz DC Supply (Vdc) Max. Amplifier Max. “A” Weighted Nominal Output
(dB re1V/1Pa) Current Drain (uA) Noise (1 kHz Impedance (Ohms) Comments
Equivalent SPL)
EM-23046-P16 -36.0±3 1.3 50 31.0 dB 4400 3-wire, 25.4 mm Shielded Cable
EM-23069-000 -36.0±3 1.3 50 33.0 dB 4400 Tubeless
Specialty Transducer Microphones
EK/EL SERIES
– Microphone
Omnidirectional (EK), Unidirectional (EL) 4.00 x 5.59 x 2.28 (mm)
EK omnidirectional microphones provide a unique combination of size, performance
and value. Its high electroacoustic sensitivity and low noise make this microphone
an excellent choice for applications where space allows. These popular microphones
are available in many model varieties.
NR SERIES
– Microphone
Noise Canceling 4.00 x 5.59 x 2.28 (mm)
The NR Series close talking microphones deliver state-of-the-art noise canceling performance.
NR microphones are used as headset microphones in the most demanding communication
and speech recognition environments. The NR Series microphones are available in boom
microphone packages. (See the FB Series and PNR/PWP Series for details.)
SPECIALTY TRANSDUCERS – Microphones
•Integral FET amplifier
•Diaphragm responds to pressure differential giving
high rejection of background noise
•Withstands severe environmental conditions
•Low vibration sensitivity
•High electoacoustical sensitivity
•Superior noise canceling performance
•Lead attachment available
10 www.knowles.com
Note: All performance curves are typical
SENSITIVITY IN dB RELATIVE TO 1.0V/0.1 Pa
FREQUENCY (Hz)
•High resistance to mechanical shock
•Available with RFI suppression
•Various port locations available
•Wide range of frequency responses
•High S/N performance
SENSITIVITY IN dB RELATIVE TO 1.0V/0.1 Pa
FREQUENCY (Hz)
MMooddeellSensitivity @1kHz DC Supply (Vdc) Max. Amplifier Max. “A” Weighted Nominal Output
(dB re1V/1Pa) Current Drain (uA) Noise (dBV) Impedance (Ohms) Comments
NR-23158-000 -38.0±3 1.3 50 -100 4400 3-wire
NR-23159-000 -52.0±3 1.3 200 -100 2500 2-wire
NR-23160-000 -44.0±3 1.3 50 -100 4400 2-wire
NR-25994-000 -38.0±3 1.3 700 -100 4400 3-wire
-40
-50
-60
-70
-80
2 3 4 5 6 7 8 9
10k
100 1k
2 3 4 5 6 7 8 9
56789
-40
-50
-60
-70
-80 2 3 4 5 6 7 8 9
10k
100 1k
2 3 4 5 6 7 8 9
MMooddeellSensitivity @1kHz DC Supply (Vdc) Max. Amplifier Max. “A” Weighted Nominal Output
(dB re1V/1Pa) Current Drain (uA) Noise (1 kHz Impedance (Ohms) Comments
Equivalent SPL)
EK-23024-C36 -33.0±2 0.9-10 50 26.0 dB 4400 RFI Improved Version
EK-23024-P07 -33.0±2 0.9-10 50 26.0 dB 4400 3-wire, 1 m Shielded Cable
EK-23027-C36 -33.0±2 0.9-10 50 100.0 dB 4400 RFI Improved Version
EK-23028-C36 -37.0±3 0.9-10 50 100.0 dB 4400 RFI Improved Version
EK-23033-C36 -33.0±2 0.9-10 50 26.0 dB 4400 RFI Improved Version
EK-23132-000 -33.0±2 0.9-10 50 26.0 dB 4400
EK-23133-C36 -33.0±2 0.9-10 50 26.0 dB 4400 RFI Improved Version
EK-23142-C37 -33.0±2 0.9-10 50 26.0 dB 4400 RFI Improved Version
EL-23078-000 -33.0±2 0.9-10 50 31.0 dB 4400
BJ SERIES
– Microphone
Omnidirectional, Noise Canceling 7.92 x 5.70 x 4.14 (mm)
Knowles’ Magnetic Microphones (BJ Series) are based on balanced armature technology and
are self-shielded against external magnetic fields. The microphones offer high efficiency,
stability, and reliability and are small in size. The diaphragm of the BJ Series responds to
pressure differential, giving high rejection of background noise. Both face and edge ports are
offered. In addition, there is a short distance between front and back ports resulting in
improved noise rejection up to higher frequencies.
BL SERIES
– Omnidirectional Microphone
Knowles’ Piezo Ceramic Microphones (BL Series) are rugged, stable and versatile.
BL microphones are available in three different package sizes: standard, thin or 0.5"
cylindrical shell and cable assembly. Both communication and broadband frequency
response versions are offered. In addition, BL microphones have high vibration sensitivity
and may be used as accelerometers.
•Balanced armature technology
•High efficiency, stability and reliability
•Self-shielded against external magnetic fields
•Face and edge ports
•Diaphragm responds to pressure differential giving high
rejection of background noise
•Short distance between front and back ports resulting in
improved noise rejection up to higher frequencies
•High sensitivity
•Wide frequency range
•Integral FET amplifier
•High resistance to mechanical shock
•Various responses
•Two case sizes available
11www.knowles.com
Note: All performance curves are typical
MMooddeellDimensions Sensitivity @ 1kHz DC Supply (Vdc) Max. Amplifier Max. “A” Weighted Nominal Output
(dB re1V/1Pa) Current Drain (uA) Noise (1 kHz Impedance (Ohms) Comments
Equivalent SPL)
BL-21671-000 7.9 x 5.6 x 4.1 -34.5±3 1.3 50 32.0 dB 13000
BL-21671-140 7.9 x 5.6 x 4.1 -34.5±4 1.3 50 32.0 dB 13000 Faster
Overpressure Recovery
BL-21785-000 7.9 x 5.6 x 2.3 -49.0±3 3 160 34.0 dB 4000
BL-21994-000 25.4 x 12.7 DIA -49.0±3 3 160 34.0 dB 4000 965 mm Shielded Cable
BL-23497-000 25.4 x 12.7 DIA -49.0±3 3 160 34.0 dB 4000 34.3 mm Leads
BL-27046-000 7.87 x 5.54 x 2.23 -49.0±3 1.3 160 34.0 dB 4000
MMooddeellDirectivity Port Location Nominal Impedance Nominal DC Resistance
at 1kHz (Ohms) at 20° C (Ohms)
BJ-21590-000 Omnidirectional OJn 3900 900
BJ-28411-000 Noise Canceling Dual 300 75.5
SPECIALTY TRANSDUCERS – Microphones
WP SERIES
– Waterproof Microphone
Omnidirectional, Noise Canceling 4.00 x 5.59 x 2.28 (mm)
Knowles’ waterproof microphones survive immersion in water. The WP Series’ form
factor is a very small size with low vibration sensitivity. The excellent noise canceling
performance is useful for sensors and instrumentation. The WP Series are available in
boom microphone packages. (See the FB Series and PNR/PWP Series for details.)
MR SERIES
– Waterproof Microphone
Omnidirectional 22.12 DIA x 9.3 (mm)
The MR Series Assemblies consist of a microphone element attached to
a waterproof bellows assembly. They may be panel mounted, attached for
boom applications, and are suitable for outdoor use or repeated submersion.
12 www.knowles.com
Note: All performance curves are typical
•Highly waterproof – no loss of performance after immersion
in 15-20 m water
•Corrosion resistant
•Withstands explosive decompression
•Design proven in rugged environments
•Cable wire attached
•High resistance to mechanical shock
•Acoustically transparent bellows
•Resists effects of mud, sand, and salt encrustation
•Waterproofed to submersion in 1m water
•Close-talking (noise-canceling)
•Corrosion resistant
•Withstands explosive decompression
•Excellent environmental performance
•High resistance to mechanical shock
SENSITIVITY IN dB RELATIVE TO 1.0V/0.1 Pa
FREQUENCY (Hz)
SENSITIVITY IN dB RELATIVE TO 1.0V/0.1 Pa
FREQUENCY (Hz)
MMooddeellSensitivity @1kHz Directivity DC Supply (Vdc) Max. Amplifier Max. “A” Weighted Nominal Output
(dB re1V/1Pa) Current Drain (uA) Noise (dBV) Impedance (Ohms) Comments
WP-23501-000 -34.0±3 Noise Canceling 1.3 300 -100 2500 2-wire, Waterproof
WP-23502-000 -32.0±3 Omnidirectional 1.3 50 -100 4400 3-wire, Waterproof
WP-23502-P07 -32.0±3 Omnidirectional 1.3 50 -100 4400 3-wire, 1 m Shielded Cable
WP-23502-P16 -32.0±3 Omnidirectional 1.3 50 -100 4400 3-wire, 25.4 mm Litz Wires
WP-23849-C36 -32.0±3 Omnidirectional 1.3 50 -100 4400 RFI Improved +
Extended Response
-35
-45
-55
-65
-75
2 3 4 5 6 7 8 9
10k
100 1k
2 3 4 5 6 7 8 9
-40
-50
-60
-70
-80
2 3 4 5 6 7 8 9
10k100 1k
2 3 4 5 6 7 8 9
MMooddeellSensitivity @1kHz DC Supply (Vdc) Max. Amplifier Max. “A” Weighted Nominal Output
(dB re1V/1Pa) Current Drain (uA) Noise (1 KHz Impedance (Ohms) Comments
Equivalent SPL)
MR-23151-000 -67.5±3 N/A N/A 30.0 dB 300 2-wire, 193 mm Leads,
Waterproof to 20 m
MR-23793-000 -40.0±4 1.3 100 31.0 dB 2500 3-wire, 201 mm Leads,
Waterproof to 20 m
MR-28406-000 -40.0±3 1.3 50 30.0 dB 3500 3-wire, 202 mm Leads,
Waterproof to 20 m
SPECIALTY TRANSDUCERS – Microphones
FB SERIES
– Boom Microphone
FB Series are available in metallic, flexible boom styles, which utilize a wide array of
microphone elements, giving superb noise rejection and high-frequency crossover of near
and far field responses. FB’s are utilized in a variety of aircraft audio systems and radio
communication helmets. Knowles offers customized lengths and end terminations to
meet your application needs.
PNR/PWP SERIES
– Boom Microphone
PNR/PWP Series are available in plastic, rigid booms, which utilize either the WP or NR
microphone element, giving superb noise rejection and high-frequency crossover of near
and far field responses. The boom microphones are utilized in a variety of aircraft audio
systems and radio communication helmets. Knowles offers customized lengths and end
terminations to meet your application needs.
13
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Note: All performance curves are typical
MMooddeellMicrophone Directivity Microphone Nominal Boom Boom Length
Element Configuration Diameter (mm) Tip-To-Tip (mm) Termination
FB-23511-000 WP-23500-000 Noise Canceling 3-WIRE 4 160 Bare End
FB-23225-000 NR-23160-000 Noise Canceling 2-WIRE 6 164 6mm Threaded
Connector
FB-25946-000 WP-23501-000 Noise Canceling 2-WIRE 4 74 Bare End
FB-25624-000 WP-23501-000 Noise Canceling 3-WIRE 5 163 Bare End
MMooddeellMicrophone Directivity Microphone Nominal Boom Boom Length
Element Configuration Diameter (mm) Tip-To-Tip (mm) Termination
PNR-23539-000 NR-23160-000 Noise Canceling 2-WIRE 4 120 Leads
PNR-23868-000 NR-25997-C97 Noise Canceling 2-WIRE NO BOOM N/A Housing Only
w/ Leads
(No Boom)
PNR-23249-000 NR-23160-000 Noise Canceling 2-WIRE 4 130 Gooseneck
Boom
•No loss of performance after submersion in 1m water
•Excellent environmental performance
•Includes RF screening — meets the 2v/m test over the frequency
range 1 to 20 MHz
•Metallic, double-spirally-wound, flexible booms which allow easy
adjustment and maintain the microphone in an optimum acoustic
position above the top lip, or close to the side of the mouth
•4mm and 6mm diameter boom options
•PWP utilizes the WP Series of electret, close-talking microphones with
the same acoustic characteristics as the NR series, but with the addition
feature of waterproofing to withstand submersion in 1m water
•The housings of the NR Series and WP Series microphones are attached
to plastic tubing, which can be customized to a particular length
•The overall PNR and PWP packages are extremely lightweight,
small and unobtrusive
SPECIALTY TRANSDUCERS – Microphones
BU SERIES –
Accelerometer 7.87 x 5.54 (mm)
BU Series Accelerometers are frequently used as contact microphones for radio
communications in high noise environments such as firefighting or combat.
The accelerometers reproduce voice signals from vibrations at the throat or from
bony parts of the head, and are compatible with helmet or headset applications.
BF Series –
Acoustic Dampers
Dampers are acoustic cloth screens for insertion inside acoustic tubing.
These damping elements are used between the speaker outlet and the ear canal
to smoothen the frequency response.
14 www.knowles.com
Note: All performance curves are typical
•Ceramic vibration transducer
•High vibration sensitivity
•Small size
•Wide frequency range
•Integral FET amplifier
•High resistance to mechanical shock
•Withstands severe environmental conditions
SENSITIVITY IN dB RELATIVE TO 1.0V/G ACCELERATION
FREQUENCY (Hz)
MMooddeellThickness Sensitivity @ DC Supply (V) Max. Current Nominal “A” Weighted
1KHz (db re 1V/g) Drain (uA) Output Impedance Noise (dBre. 1V)
@1 KHz (Ohms)
BU-21771-000 4.06 -45.0±4.5 1.5 50 5200 -103
BU-23173-000 4.06 -39.0±4.5 1.5 50 5200 -103
BU-23842-000 2.24 -40.0±4.0 1.5 50 5200 -103
BU-27135-000 2.24 -45.0±4.5 1.5 300 5200 -103
-25
-35
-45
-55
-65
2 3 4 5 6 7 8 9 10k100 1k
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
MMooddeellColor Nominal Acoustic PLUG (mm) SCREEN (mm)
Resistance (Ohms)
BF-1859-000 White 680 2.08 --
BF-1860-000 Brown 1000 2.08 --
BF-1861-000 Green 1500 2.08 --
BF-1921-000 Red 2200 2.08 --
BF-1922-000 Orange 3300 2.08 --
BF-1923-000 Yellow 4700 2.08 --
BF-1988-000 White 680 -- 1.12
BF-1991-000 Green 1500 -- 1.12
BF-1995-000 Red 2200 -- 1.12
BF-1997-000 White 680 -- 1.78
BF-1999-000 Grey 330 2.08 --
BF-3034-000 Grey 330 -- 1.78
BF-3035-000 Brown 1000 -- 1.78
BF-3036-000 Orange 3300 -- 1.78
BF-3037-000 Red 2200 -- 1.78
BF-3038-000 Green 1500 -- 1.78
BF-3039-000 Green 1500 -- 1.37
BF-3163-000 Yellow 4700 -- 1.12
•Smoothen and shape frequency response
•Various acoustical resistances and sizes
SPECIALTY TRANSDUCERS – Accelerometers & Dampers
TWFK SERIES –
Dual Balanced Armature Speaker 5.00 x 2.73 x 3.86 (mm)
The world’s smallest dual balanced armature speaker, the TWFK is designed for
pro-audio in-ear applications. Enables customized cross-over systems to achieve
target frequency response in a package size smaller than the ED Series.
WBFK SERIES –
Wideband Balanced Armature Speaker 5.00 x 2.73 x 1.93 (mm)
Same package size as FK Series, WBFK has extended high frequency response.
It is recommended as a high frequency component to be combined with low/
midrange speaker for music earphones.
15
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Note: All performance curves are typical
Knowles sub-miniature speaker designs are based on balanced armature technology and are
utilized in a variety of high performance audio and communication products. Knowles balanced
armature speakers are available in several sizes and efficiencies, which can be finely tuned to
meet your specific performance requirements. They are designed for use in in-ear applications,
including earphones and communication earpieces, or be sub-assembled by Knowles for
premium consumer electronics accessories.
•High efficiency, stability and reliability
•Customizable performance and port locations
•Ideal for premium in-ear designs
•Component and subassembly solutions
Specialty Transducer Speakers
SPECIALTY TRANSDUCERS – Speakers
•Single sound port for simplified earphone design
•Extreme wideband frequency response
•Unique woofer/tweeter combination
•Enables leading-edge earphone designs for size and performance
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
TWFK-30017-000 95 12S 31 106 113
•Lower low/mid-band sensitivity compared to FK Series
•Best high frequency response of any Knowles element
•Combine with low/mid-range speaker for
extended frequency response
•TWFK pairs WBFK with low frequency FK
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
WBFK-30095-000 91 12S 13.5 101 114
2 3 4 5 6 7 8 9
2 3 4 5 6 7 8 9
SENSITIVITY IN dB RELATIVE TO 20µPa
FREQUENCY (Hz)
110
105
100
95
90
85
80
75
70
10k100 1k
2 3 4 5 6 7 8 9
2 3 4 5 6 7 8 9
SENSITIVITY IN dB RELATIVE TO 20µPa
FREQUENCY (Hz)
110
105
100
95
90
85
80
75
70
10k100 1k
FK SERIES –
Balanced Armature Speaker 5.00 x 2.73 x 1.93 (mm)
The world’s smallest balanced-armature speaker, the FK Series is designed
for applications where size is the most important design concern.
FH SERIES –
Balanced Armature Speaker 5.09 x 2.80 x 2.59 (mm)
The FH speaker represents an unprecedented combination of ultra-compact size and high SPL
output with efficiencies normally found only in much larger speakers. The FH speaker
line brings true high-gain, high-output performance to earphone designs.
16 www.knowles.com
Note: All performance curves are typical
•Undamped, screen damped, internally damped, and Ferrofluid
™
damped responses
•Various port locations, coil impedances, damping options,
termination configurations, and frequency responses available
•Maximum SPL output of 123dB at resonance peak, 109dB
at midband (500Hz)*
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
FH-23375-000 100 12S 335 108.5 123
FH-23377-000 100 12S 685 108.5 123
FH-23821-000 100 12S 174 108.5 123
FH-26553-000 100 12S 90 108.5 123
•114dB SPL maximum output
•Two-terminal zero-bias configuration
•Undamped, screen damped, and internally damped responses
•Wide range of coil impedances
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
FK-23451-000 95.5 12S 450 104.5 118.5
FK-23466-000 95.5 12S 450 104.5 118.5
FK-26260-000 96 12S 180 104.5 115.5
2 3 4 5 6 7 8 9
SENSITIVITY IN dB RELATIVE TO 20µPa
FREQUENCY (Hz)
120
115
110
105
100
95
90
85
80
10k100 1k
2 3 4 5 6 7 8 9
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
SENSITIVITY IN dB RELATIVE TO 20µPa
FREQUENCY (Hz)
120
115
110
105
100
95
90
85
80
10000100 100
SPECIALTY TRANSDUCERS – Speakers
WBHC SERIES –
Balanced Armature Speaker 5.16 x 3.51 x 3.00 (mm)
The advanced design of the HC Series speaker provides extended acoustic bandwidth for
hi-fi in-ear speakers when paired with a low frequency speaker.
HC SERIES –
Balanced Armature Speaker 5.16 x 3.51 x 3.00 (mm)
Knowles balanced-armature, magnetic technology to give high efficiency, stability
and reliability. HC Series provides increased low frequency dynamic range in a
package size equal to FC.
FC SERIES –
Balanced Armature Speaker 5.18 x 3.55 x 3.00 (mm)
FC Series speakers may be used for small radio communication earphones where ED
size does meet package requirements. Rounded corners make it slightly smaller
compared to EH Series speakers.
Note: All performance curves are typical
17
www.knowles.com
•Available in High-Output HC speaker version
•Two-terminal zero-bias and three-terminal center-tapped configurations
•Undamped, screen damped, internally damped, and
Ferrofluid™ damped responses
•Rounded corners for improved fit rates; 10% smaller cross-section
compared to EH speaker
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
FC-26171-000 104 12C 170 112 127
FC-26887-000 100 12C 425 110.5 116
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
SENSITIVITY IN dB RELATIVE TO 20µPa
FREQUENCY (Hz)
120
115
110
105
100
95
90
85
80
10000100 100
2 3 4 5 6 7 8 9
SENSITIVITY IN dB RELATIVE TO 20µPa
FREQUENCY (Hz)
120
115
110
105
100
95
90
85
80
10k100 1k
2 3 4 5 6 7 8 9
SPECIALTY TRANSDUCERS – Speakers
•Lower low/mid band sensitivity compared to HC series
•Combine with low/mid-range speaker for extended
frequency response
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
WBHC-23910-000 95 12C 130 105 115
FREQUENCY (Hz)
120
115
110
105
100
95
90
85
80 2 3 4 5 6 7 8 9
10k
100 1k
2 3 4 5 6 7 8 9
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
HC-23761-000 101 12C 8.4 114 116
•High-output technology provides double (+3dB) the maximum
acoustic output of existing Knowles FC Series speakers
•Maximum output comparable to Knowles’ ED Series speaker
in a package size only 68% as large!
•Same size and dimensions as Knowles’ EH Series
•Ideal for applications where small size and high output is required
SENSITIVITY IN dB RELATIVE TO 20µPa
EH SERIES –
Balanced Armature Speaker 5.19 x 3.55 x 3.00 (mm)
EH Series speakers are approximately 2/3 the size of ED speakers and may be used for small
radio communication earphones where ED size does not meet package requirements.
ES SERIES –
Balanced Armature Amplified Speaker 5.18 x 3.54 x 3.04 (mm)
EH size speaker with integrated Class D power amplifier
EP SERIES –
Balanced Armature Amplified Speaker 6.32 x 4.29 x 2.99 (mm)
Based on Knowles’ versatile and popular ED speaker, the EP series adds the benefits of
an internal Class-D amplifier. Its compact size and appreciable output power make the EP
speaker suitable for a variety of designs.
18 www.knowles.com
Note: All performance curves are typical
•Class D amplified magnetic speaker
•Self-shielded to reduce magnetic radiation
•125dB SPL maximum output
•Three-terminal electrical connection
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
EP-24075-000 106 12C 50000 116.5 124
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
ES-23127-000 101 12C 50000 112 117.5
ES-23140-000 101 12C 50000 112 115.5
•EH micro speaker, but with internal, highly-efficient, class D amplifier
•Lower current drain prolongs battery life
•Lower distortion
•Available in a range of SPL ratings
FREQUENCY (Hz)
120
115
110
105
100
95
90
85
80 2 3 4 5 6 7 8 9
10k
100 1k
2 3 4 5 6 7 8 9
SENSITIVITY IN dB RELATIVE TO 20µPa
FREQUENCY (Hz)
120
115
110
105
100
95
90
85
80
2 3 4 5 6 7 8 9
10k
100 1k
2 3 4 5 6 7 8 9
SENSITIVITY IN dB RELATIVE TO 20µPa
SPECIALTY TRANSDUCERS – Speakers
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
EH-23030-000 100 12C 625 109 126.5
EH-23149-000 100 12C 110 109 126.5
EH-27479-000 100 12C 150 109 123
•Balanced-armature, magnetic technology to give high efficiency,
stability and reliability
•High sensitivity
•Various responses, including standard, damped and modified
•Low distortion
•Self-shielded for low magnetic radiation
FREQUENCY (Hz)
120
115
110
105
100
95
90
85
80 2 3 4 5 6 7 8 9
10k
100 1k
2 3 4 5 6 7 8 9
SENSITIVITY IN dB RELATIVE TO 20µPa
FED SERIES –
Balanced Armature Speaker 6.32 x 4.31 x 2.47 (mm)
The addition of
Ferrofluid
™to Knowles ED series speakers improves mechanical shock
survival and provides peak damping to smooth frequency response.
ED SERIES –
Balanced Armature Speaker 6.32 x 4.31 x 2.97 (mm)
One of Knowles’ most versatile and most popular speakers, its compact size and appreciable
output power make the ED speaker suitable for a variety of instruments.
Note: All performance curves are typical
19
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•Ferrofluid
™
damped with 2dB, 4dB, or 6dB peak amplitude
•Superior shock performance and reduced speaker vibration
•Two-terminal zero-bias and three-terminal center-tapped configurations
•Numerous port locations and coil impedances
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
FED-26792-I04 102.5 12C 65 114.5 116.5
FED-30048-I04 102 12N 26 111.5 116
FREQUENCY (Hz)
120
115
110
105
100
95
90
85
80
75
70 2 3 4 5 6 7 8 9
10k
100 1k
2 3 4 5 6 7 8 9
SENSITIVITY IN dB RELATIVE TO 20µPa
SPECIALTY TRANSDUCERS – Speakers
•Undamped, screen damped, internally damped, and Ferrofluid
™
damped responses
•Numerous port locations and coil impedances
•High efficiency and low distortion
SENSITIVITY IN dB SPL
FREQUENCY (Hz)
125
115
105
95
85
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
10k
100 1k
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
ED-21744-000 104 12C 1700 111.5 123
ED-21913-000 104 12C 780 112 127
ED-23147-000 102.5 12C 48 110 120.5
ED-23619-000 104 12C 7.1 112 127
ED-23801-000 104 12S 196 112 122
ED-23814-000 104 12S 50 112 128
ED-26245-000 104 12C 55 112.2 122
ED-26598-000 102.5 12C 395 115.5 115.5
ED-26821-000 102.5 12C 7.1 116 120.5
ED-27045-000 104 9C 395 112 127
ED-27230-000 104 12C 79 112 127
ED-27304-000 104 12C 290 111.5 127
ED-29689-000 104 12C 7.1 112 127
EC SERIES –
Balanced Armature Speaker 7.57 x 4.31 x 3.67 (mm)
EC Series speakers are commonly used in isolating earphones for radio communication.
TEC SERIES –
Balanced Armature Speaker 7.87 x 4.09 x 2.79 (mm)
The TEC combines output comparable to the larger BK speaker in an ultra-thin package.
The TEC is suitable for multi-element earphone designs.
DTEC SERIES –
Balanced Armature Speaker 7.87 x 4.09 x 5.59 (mm)
The DTEC Series combines two TEC speaker elements with a single round port.
Case size is equivalent to BK/EF. DTEC provides increased output and reduced
vibration compared to a single speaker.
20 www.knowles.com
Note: All performance curves are typical
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
EC-23097-000 108 12S 200 115 130
EC-23098-000 108 12S 425 115 130
EC-26368-000 108 12S 54 114 129
•Similar SPL output to the BK Series
•Rounded corners on the face opposite the terminal pad
•34% smaller volume than the BK Series
FREQUENCY (Hz)
125
120
115
110
105
100
95
90
85 2 3 4 5 6 7 8 9
10k
100 1k
2 3 4 5 6 7 8 9
SENSITIVITY IN dB RELATIVE TO 20µPa
SPECIALTY TRANSDUCERS – Speakers
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
TEC-30033-000 119 12C 31 117 129
•Ultra-thin
•Wideband output
•DTEC combines two TEC elements
•Enables small multi-element designs
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
DTEC-30008-000 121 12S 31.5 123.5 131.5
•Dual elements with single sound port
•More output than BK in equal package size
•Reduced vibration compared to BK
•Improved frequency response compared to BK
2 3 4 5 6 7 8 9
SENSITIVITY IN dB RELATIVE TO 20µPa
FREQUENCY (Hz)
130
125
120
115
110
105
100
95
90
85
80
10k100 1k
2 3 4 5 6 7 8 9
SENSITIVITY IN dB RELATIVE TO 20µPa
FREQUENCY (Hz)
130
125
120
115
110
105
100
95
90
85
80
10k100 1k
2 3 4 5 6 7 8 9
2 3 4 5 6 7 8 9
BK SERIES –
Balanced Armature Speaker 7.87 x 5.59 x 4.01 (mm)
BK Series speakers provide broadband performance at value pricing. They are commonly
used for full range in-ear speakers and communications utilizing an earplug design.
CM SERIES –
Balanced Armature Speaker 8.38 x 16.64 DIA (mm)
The CM Series delivers the benefits of balanced armature technology in a compact finished
package. The CM is ideal for use in situations where a non-contacting headset is required,
but signal voltage is limited – as is common for radios and wireless telephones. The CM
also conserves battery power, and provides static shock protection for the user.
Note: All performance curves are typical
21
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•Balanced-armature, magnetic technology to give high efficiency,
stability and reliability
•High acoustic efficiency enables sufficient sound output even
when limited power is available
•In-built static protection
•Lightweight, matt-black, plastic housing
•Ergonomically designed with rounded edge to fit the concha
•High-quality sound output
•Tailored bandwidth for superb speech intelligibility
SENSITIVITY IN dB SPL
FREQUENCY (Hz)
125
115
105
95
85
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
10k
100 1k
•High efficiency and low distortion
•Various port locations, coil impedances, damping options,
terminal configurations, and frequency responses available
SENSITIVITY IN dB SPL
FREQUENCY (Hz)
135
125
115
105
95
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
10k
100 1k
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
BK-21600-000 123 12S 285 118 133
BK-21604-000 123 12S 2320 118 133
BK-21610-000 121 12S 60 126.5 136
BK-21613-000 118 1S 450 118 134
BK-21615-000 118 12S 450 118 134
BK-21669-000 123.5 12C 24 118 134
BK-23134-000 118 12S 285 118 134
BK-26824-000 119 12S 16 118 129
BK-28507-000 126 12S 13.3 122.5 136
BK-28510-000 126 12S 320 123 135
BK-28562-000 123 12S 23 119 131
BK-29725-000 118 12S 285 118 128
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
CM-23152-000 103 Face 150 114.5 129
CM-23299-000 103 Face 150 114.5 119
CM-28421-000 103 Face 360 114.5 119
CM-28431-000 103 Face 30 114.5 119
CM-28452-000 103 Face 360 114.5 119
SPECIALTY TRANSDUCERS – Speakers
SR SERIES –
Balanced Armature Speaker 8.84 DIA x 5.00 (mm)
At 8.8mm diameter, the SR is the first round balanced armature speaker in the
marketplace. SR offers output equivalent to the BK series and maximizes
bass performance.
CI SERIES –
Balanced Armature Speaker 9.47 x 7.18 x 4.10 (mm)
Knowles’ largest and most powerful speaker, the CI series is the speaker of choice.
With its high efficiency and a 143dB SPL maximum output, the CI speaker provides
optimal low frequency performance.
22 www.knowles.com
Note: All performance curves are typical
•Two-terminal zero-bias and three-terminal
center-tapped configurations
•Various port locations, coil impedances,
termination configurations, and frequency
responses available
SENSITIVITY IN dB SPL
FREQUENCY (Hz)
135
125
115
105
95
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
10k
100 1k
•Round package facilitates earphone designs
•Drop-in upgrade for moving coil dynamic speakers
•Designed for high volume production
•Balanced armature technology
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
SR-8850NSS-000 113 Face 37 124.5 130.5
SR-8850NWS-000 114.5 Face 21.5 123 132
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
CI-22748-000 125 12C 250 128.5 138.5
CI-22762-000 125 1S 175 128.5 138.5
CI-22955-000 125 12C 68 @ 1kHz 128.5 138.5
CI-22960-000 125 12C 400 128.5 138.5
CI-28487-000 125 1S 100 @ 1kHz 128.5 138.5
CI-28597-000 125 11S 68 @ 1kHz 128.5 138.5
FREQUENCY (Hz)
130
125
120
115
110
105
100
95
90
85
80 2 3 4 5 6 7 8 9
10k
100 1k
2 3 4 5 6 7 8 9
SENSITIVITY IN dB RELATIVE TO 20µPa
SPECIALTY TRANSDUCERS – Speakers
MR SERIES –
Waterproof Speaker 22.12 DIA x 9.3 (mm)
The MR Series Assemblies consist of a speaker element attached to a waterproof
bellows assembly. They may be panel mounted, and are suitable for outdoor use
or repeated submersion.
CB SERIES –
Balanced Armature Speaker 25.15 x 25.15 x 9.65 (mm)
The CB Series Transceiver offers high electro-acoustic efficiency to conserve power in
push-to-talk radio handsets and other battery operated equipment. The CB is available
with mounting pins to facilitate assembly to a PC board. Model CB-23817-000 is designed
to survive submersion in water.
Note: All performance curves are typical
23
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•Excellent sound quality
•High speech intelligibility, stability, and reliability
•Suitable for PCB mounting
•Can function as a microphone or beeper
•Various impedances
•Face and edge port locations available
SENSITIVITY IN dB SPL
FREQUENCY (Hz)
90
80
70
60
50
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
10k
100 1k
•Highly waterproof – no loss of performance after
immersion in 15m water
•Corrosion resistant
•Withstands explosive decompression
•Design proven in rugged environments
•Leads attached
•High resistance to mechanical shock
•Acoustically transparent bellows
•Resists effects of mud, sand, and salt encrustation
SENSITIVITY IN dB SPL
FREQUENCY (Hz)
125
115
105
95
85
2 3 4 5 6 7 8 9
10k
100 1k
2 3 4 5 6 7 8 9
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
MR-23333-000 100 Face 21 110 129
Sensitivity @ 1kHz Impedance @ 500Hz Max SPL @ 500Hz Max SPL @ 1st Peak
MMooddeell(dB SPL) Port Location (Ohms) (dB SPL) (dB SPL)
CB-22849-000 73 Edge 24 80.5 96.5
CB-22850-000 73 Edge 48 80.5 96.5
CB-23817-000 83 Edge 48 95 107
SPECIALTY TRANSDUCERS – Speakers
CUSTOM ASSEMBLIES
24 www.knowles.com
Manufacturing Services
• Assembly
• Cabling
• Testing
• Utilization of Knowles Acoustic components
Design Support
• Industrial
• Mechanical
• Application Tuning
COMPLETE SOLUTION
Knowles Acoustics Finished Goods program offers reduced time to market at an ultimately reduced total manufacturing cost of acoustic product
ownership. Support in design, application, assembly and testing are all elements included in our services. Off-the-shelf designs are also available.
MARKET APPLICATIONS
Ultimately, our mission is to improve the acoustic interface and simplify the manufacturing process for customers. Our long term acoustic history
provides the expertise for markets and customers of:
FINISHED GOODS
Wherever your design ideas take you, Knowles Acoustics
can support your need for customized audio assemblies.
Our custom Finished Goods offer a turnkey solution
utilizing the acoustic expertise and components of
Knowles Acoustics.
• Mobile media products
• Industrial communications
• Consumer electronics applications
Assembly Designs MP3 Mobile Phone Smart Phone/PDA Notebook Industrial Comm.
Single Ear
✔✔ ✔
Stereo
✔✔ ✔ ✔ ✔
Microphone
✔✔✔✔
Collaborate in-depth with Knowles Acoustics to arrive at an integrated component and assembly design to manufacture for you.
MARKET MATRIX
ACOUSTIC SOFTWARE
Note: All performance curves are typical
INTELLISONIC™
The intelligibility and use of mobile communications
are often impeded by the impact of noise from the
immediate environment. IntelliSonic is a software-based
speech enhancement technology that when coupled
with Knowles’ microphones, reduces the effects of
reverberation, directionally interfering speech,
background noise and annoying acoustic echo.
COMPLETE SOLUTION – Integrated Systems
When you consider the interdependency of microphone design, acoustic porting, and sound signal conditioning, it's easy to see why Knowles
Acoustics has taken an integrated approach to your acoustic system needs.
• VoIP Telephony
• Command and Control
• Voice recognition
• Dictation
APPLICATIONS
Platforms such as tablets, laptops, ultra-mobile personal computers (UPCs), and other mobile computing devices have a number of applications that
would benefit from IntelliSonic to enhance the user experience and final product perception.
PRODUCT MATRIX
MICROPHONES TECHNOLOGY ACOUSTIC PORTING INTELLISONIC SOFTWARE
Product Code # of Microphones Noise Reduction Acoustic Array Echo Cancellation
DX01 1
✓
––
DX02 2
✓✓
–
DXEC01 1
✓
–
✓
DXEC02 2
✓✓ ✓
• Language Translation
• Voice Annotation
• Audio Note Taking
• Noise suppression 16 dB
• Interference cancellation via beam-forming array 30dB
• Acoustic echo cancellation 27dB
• Speech bandwidth 8kHz
• Adjustable acceptance and look angles
• Fully adaptive system adapts to changing
acoustic environment
• Upper filter driver adherent to Microsoft’s windows
driver model (WDM)
• Rich application programming interface (API) set
• Real-time processing
• Low speech distortion
LICENSING
A license per end user copy is recommended. This allows access to continued improvements and new releases. The license fee is dependent upon
volumes and product platforms.
SUPPORTED PLATFORMS
• Operating System: Windows®XP/2000 (supports AC’97 and HDAudio), Windows CE
IntelliSonic
™
Attenuates Unwanted Sounds
(Visual output of recordings using same microphone)
Unprocessed
Signal
Using
IntelliSonic
™
FEATURES
25
www.knowles.com
MICROPHONE AND SPEAKER BASICS
26 www.knowles.com
MICROPHONES
Microphones measure sound pressure. Inside a Knowles microphone is a thin flexible diaphragm, an electrically
charged plate, and an amplifier (Fig. 1). The output voltage is proportional to changes in the small separation
between the diaphragm and the charged plate (Fig. 2).
As sound pressure inside the front cavity increases, the diaphragm is pushed closer to the plate. As the
pressure decreases, it moves further away. The motion of the diaphragm produces a small electrical signal that
is amplified by a miniature circuit inside the microphone.
The sensitivity of a typical Knowles’ microphone is measured in units of dB relative to 1 Volt per 0.1 Pascal.
MICROPHONE AND SPEAKER BASICS
Fig 1: Cross section of a Knowles EM microphone
OUTPUT TERMINAL
CHARGE PLATE DIAPHRAGM FRONT CAVITY
WIRE
SOUND PRESSURE
FIG. 2: EM diaphragm and electret
CHARGE PLATE
DIAPHRAGM AIR GAP SEPARATION
AMPLIFIER
MICROPHONE AND SPEAKER BASICS
Note: All performance curves are typical
27
www.knowles.com
SPEAKERS
The speaker converts an electrical signal into sound. A cross section of a typical Knowles speaker is shown in Fig. 3.
The basic components of the speaker are: a coil of wire, a metal U-shaped reed called the armature, a pair of permanent
magnets, a drive rod, and a diaphragm.
The coil and armature act as an electromagnet. An alternating current in the coil causes the polarity of the armature to
switch back and forth from north to south. The free end of the armature bends slightly up and down as it is attracted
alternately to the top and bottom magnets (Fig. 4). The diaphragm, pulled along by the drive rod, pumps air in and out of
the speaker. The mechanical motion of the armature is thus converted into sound.
The sound output of a typical Knowles’ speaker is measured in units of dB SPL (sound pressure level) relative to 20 µPa.
Fig. 3: Cross section of a Knowles EH speaker
OUTPUT TERMINAL COIL DRIVE ROD DIAPHRAGM
MAGNETS
ARMATURE
Fig. 4: The motor of the speaker has a coil, an armature, and a pair of permanent magnets.
World Headquarters
Knowles North &
South America
Knowles Europe,
Africa & Middle
East
Knowles Australia
Knowles Singapore
Knowles Malaysia
Knowles Taiwan
Knowles China
Knowles Japan
Knowles Korea
Manufacturing
Sales & Application Engineering
AMERICAS EMEA / ASIA PACIFIC
Globally Positioned
AMERICAS:
Knowles Acoustics
1151 Maplewood Drive
Itasca, IL 60143 U.S.A.
Phone: 630-250-5930
Fax: 630-250-5932
EUROPE:
Knowles Acoustics
York Road, Burgess Hill
West Sussex, RH15 9TT
England
Phone: +44-1444-235432
Fax: +44-1444-248724
JAPAN:
Knowles Acoustics
2-2-16 Sangenjaya
Setagaya-Ku, Tokyo
154-0024 Japan
Phone: 81-3-5779-8503
Fax: 81-3-5779-8523
KOREA:
Knowles Acoustics
#1212 Dongbu Root Building, 16-2
Sunae-Dong
Bundang-Ku, Sungnam-Shi
Kyunggi-Do, Korea
Phone: 82-31-712-2223
Fax: 82-31-712-3314
ASIA:
Knowles Acoustics
5F, No. 129, Lane 235, Bauchiau Rd.
Shindian City, Taipei 23145, Taiwan
Phone: 886-2-8919-1799
Fax: 886-2-8919-1798
Knowles Acoustics maintains sales, marketing, engineering and manufacturing globally.
For immediate assistance on your specific requirements, please call the nearest facility listed below.
www.knowles.com
© 2007 Knowles Acoustics Printed In USA
KA-003-12-07V3
