BEYERDYNAMIC Classis BM 42 W 723797, Classis BM 42 BC 729507 Classis BM 42 Spec Sheet A2.pdf

Classis BM 42

Boundary Microphone

FEATURES

• Semi-cardioid

• RFI-proof due Scudio™ technology

• High-quality non-glare design

• Linear frequency response

• High gain before feedback

• Reduced diffuse room noise

• Suitable for miking speech

TECHNICAL SPECIFICATIONS

Transducer type . . . . . . . . . . . . . . . . . . . Condenser

(back-electret)

Operating principle. . . . . . . . . . . . . . . . . Pressure gradient

Frequency response . . . . . . . . . . . . . . . . 55 - 20,000 Hz

Polar pattern . . . . . . . . . . . . . . . . . . . . . Semi-cardioid

Open circuit voltage . . . . . . . . . . . . . . . . 13.3 mV/Pa = -37.5 dBV

Nominal impedance . . . . . . . . . . . . . . . . < 200 Ω

Nominal output impedance . . . . . . . . . . ≥ 1 kΩ

Max. SPL at 1 kHz. . . . . . . . . . . . . . . . . . 114.2 dB

Dynamic range . . . . . . . . . . . . . . . . . . . . 84 dB

Signal-to-noise ratio . . . . . . . . . . . . . . . . 63.9 dB [A, RMS]

Noise voltage . . . . . . . . . . . . . . . . . . . . . 8.4 µV [A, RMS]

A-weighted equivalent SPL . . . . . . . . . . . 30.1 dB

Phantom supply . . . . . . . . . . . . . . . . . . . 8 - 52 V

Current consumption . . . . . . . . . . . . . . . approx. 2.1 mA

Dimensions without connector

((L x W x H). . . . . . . . . . . . . . . . . . . . . . . 86 x 61 x 21 mm

[3.39" x 2.40" x 0.83"]

Weight with cable . . . . . . . . . . . . . . . . . 213 g [7.51 oz]

APPLICATIONS

The Classis BM 42 is a small condenser boundary microphone with
a semi-cardioid polar pattern. The robust housing is of a high­quality design and covered with a very exclusive, dust repellent
fabric. Due to the linear frequency response the microphone can
be used for a number of applications, for which a microphone
mounted on a stand cannot be used. The matt, non-glare surface
allows integrating the Classis BM 42 discretely into each installation
placing the microphone on conference tables, lecterns, round tables
or on altars. It also can be used on theatre stages or for live
recordings. The integrated high pass filter reduces low-frequency
noise from tables and other.
The principle of a directional boundary microphone has several
advantages:

• The semi-cardioid polar pattern of the Classis BM 42 provides in
contrast to standard boundary microphones a better gain-before­feedback and reduces ambient noise.

• The increase of the sound pressure at a boundary results in a
higher gain, signal-to-noise ratio and comb filter effects cannot
occur.

The Classis BM 42 is available in matt black or white.

VERSIONS

Classis BM 42 B black, integrated pre-amp,

bare-ended 3 m

long cable . . . . . . . . . . . . . Order # 723.789

Classis BM 42 W white, integrated pre-amp,

bare-ended 3 m

long cable . . . . . . . . . . . . . Order # 723.797

Classis BM 42 BC black, integrated pre-amp,

3 m long cable with
3-pin male XLR connector . Order # 729.507

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beyerdynamic GmbH & Co. KG
Theresienstr. 8 | 74072 Heilbronn – Germany
Tel. [phone] / 617 - 0 | Fax [phone] / 617 - 204
[e-mail] | www.beyerdynamic.com

For further distributors worldwide, please go to www.beyerdynamic.com
Non-contractual illustrations. Contents subject to change without notice. E2 / Classis BM 42 (07.16)

Classis BM 42

FREQUENCY RESPONSE & POLAR PATTERN

This frequency response curve (measuring tolerance ± 2.5 dB) and polar pattern correspond to a typical production sample for this microphone.

Frequency response curve ± 2.5 dB 0 dB 13.3 mV/Pa Classis BM 42

Horizontal, 60° Elevation

Vertical

^

=

ARCHITECT’S AND ENGINEER’S SPECIFICATIONS

The microphone shall be a fixed-charge condenser designed for use
in table or panel-mount boundary applications. It shall have a
frequency response of 55 Hz to 20,000 Hz and a semi-cardioid
polar pattern. It shall have a built-in phantom power module and
shall operate from an external 8V to 52V DC phantom power
source. The filter in the microphone grille shall eliminate wind and
pop noise. The RFI shield technology shall eliminate radio frequency
interference of wireless communication devices. It shall be capable
of handling sound input levels up to 114,2 dB with a dynamic range
of 84 dB. Nominal open circuit output voltage shall be 13.3 mV/Pa
at 1 kHz. Output shall be low impedance balanced (<200 ohms).
The microphone shall have a maximum size of 86 x 61 x 21 mm
(3.39" x 2.40" x 0.83"). Weight shall be 213 grams (7.51 oz). The
microphone shall provide an unobtrusive full metal housing for
discreet positioning. The steel mesh grille shall be covered by fa­bric. Finish shall be non-glare mat black [white]. Rubber pads shall
be mounted for reduction of mechanical noise transfer from the
mounting panel. The microphone shall have a bare-ended 3 meter
long cable [3-pin male XLR connector].

WIRING DIAGRAM

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beyerdynamic GmbH & Co. KG
Theresienstr. 8 | 74072 Heilbronn – Germany
Tel. [phone] / 617 - 0 | Fax [phone] / 617 - 204
[e-mail] | www.beyerdynamic.com

For further distributors worldwide, please go to www.beyerdynamic.com
Non-contractual illustrations. Contents subject to change without notice. E2 / Classis BM 42 (07.16)

Manufacturer: beyerdynamic
Type: Classis BM 42 B [W, BC]