Shure BETA 91A manual Load Impedance, Power Requirements, Specifications, Accessories and Parts

Load Impedance

Maximum SPL capability, output clipping level, and dynamic range vary with the in- put load impedance of the preamplifier to which you connect the microphone. Shure recommends a minimum input load impedance of 1000 Ω. Most modern microphone preamplifiers meet this requirement. Higher impedance results in better performance for these specifications.

Power Requirements

This microphone requires phantom power and performs best with a 48 Vdc supply (IEC-61938). However, it will operate with slightly decreased headroom and sensitivity with supplies as low as 11 Vdc.

Most modern mixers provide phantom power. You must use a balanced microphone cable: XLR-to-XLR or XLR-to-TRS.

SPECIFICATIONS

Cartridge Type	Electret Condenser
Polar Pattern	Half-cardioid (cardioid in hemisphere above mount-
	ing surface)
Frequency Response	20 to 20,000 Hz
Output Impedance	146 Ω
@ 1 kHz
Sensitivity	–48.5 dBV/Pa[1] (3.8 mV)
open circuit voltage, @ 1 kHz, typical
Maximum SPL	2500 Ω load	155 dB
1 kHz at 1% THD[2]	1000 Ω load	151 dB
Signal-to-Noise Ratio[3]	64.5 dB
Dynamic Range	2500 Ω load	125.5 dB
@ 1 kHz	1000 Ω load	121.5 dB
Clipping Level	2500 Ω load	12.5 dBV
20 Hz to 20 kHz, 1% THD	1000 Ω load	7.5 dBV
Self Noise	29.5 dB SPL-A
equivalent SPL, A-weighted, typical
Common Mode Rejection	≥55 dB
20 Hz to 200 kHz
Frequency Contour Switch	7 dB of attenuation centered at 400 kHz
Connector	Three-pin professional audio (XLR), male, balanced
Polarity	Positive pressure on diaphragm produces positive
	voltage on pin 2 with respect to pin 3
Power Requirements	11–52 V DC[4] phantom power (IEC-61938), 5.4 mA
Net Weight	470 g (16.6 oz.)

[1]1 Pa=94 dB SPL

[2]THD of microphone preamplifier when applied input signal level is equivalent to cartridge output at specified SPL

[3]S/N ratio is the difference between 94 dB SPL and equivalent SPL of self noise, A-weighted

[4]All specifications measured with a 48 Vdc phantom power supply. The microphone operates at lower voltages, but with slightly decreased headroom and sensitivity.

Accessories and Parts

Furnished Accessories

Zippered Carrying Bag 95A2314

Optional Accessories

7.6 m (25 ft.) Cable C25E

Replacement Parts

Cardioid Cartridge RPM98A/C

CERTIFICATION

Eligible to bear CE Marking. Conforms to European EMC Directive 2004/108/EC. Meets Harmonized Standards EN55103-1:1996 and EN55103-2:1996, for residential (E1) and light industrial (E2) environments.

The Declaration of Conformity can be obtained from:

Authorized European representative: Shure Europe GmbH

Headquarters Europe, Middle East & Africa Department: EMEA Approval Wannenacker Str. 28

D-74078 Heilbronn, Germany Phone: +49 7131 72 14 0 Fax: +49 7131 72 14 14 Email: EMEAsupport@shure.de

4