Shure KSM27 manual Setting Attenuation, Integral Pop Filter, Load Impedance

Setting Attenuation

The attenuation switch on the back of the KSM27 reduces the signal level from the cartridge by 15 dB without altering the frequency response. This can prevent extremely high SPLs (ie. close miked drums and guitar cabinets) from overloading the microphone. To activate attenuation, move the switch to the “-15 dB” position.

0 dB – Use this switch for “quiet” to “normal” sound levels.

-15 dB – Use this switch position when in close proximity with extremely loud sound sources such as kick drum, snare drum, or loud guitar cabinets.

Integral Pop Filter

The KSM27 grille consists of 3 separate mesh layers that act as an integral pop filter which helps reduce wind and breath noise. Depending on the performer, an external pop-protection screen or windscreen (See Figure 3) may be necessary when close-miking vocalists.

FIGURE 3. PS–6 POPPER STOPPERT POP FILTER

Load Impedance

Shure recommends a load impedance of at least 1000 Ω. When used with modern microphone preamplifiers (rated at 2500 Ω), the KSM27 provides higher maximum SPL capability and output clipping level. When the attenuation switch is set to the –15 dB position, the KSM27 can handle sound pressure levels of up to 152 dB and output +15 dBV into a load of 2500 Ω or greater.

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