Alesis ACTIVE M1 Quick Start Owner's Manual page 9

8. Lo – This high-pass filter switch lets you pick the point at which the speaker
will roll off low frequencies. Many subwoofers roll off frequencies above 80 Hz,
so if you want to use your M1Active 520/620 speakers with a subwoofer, set this
switch to "80." If you do not have a subwoofer, leave this set to the lowest
number to let the M1Active 520/620 play its full range of sound.
Alternatively, you may want to hear how your mix will translate on smaller
speakers (such as a TV, or radio). Set this switch to 80Hz or 100Hz (if you have a
subwoofer, turn it off) and you'll get a sense of how your mix will sound on
smaller speakers with reduced bass output.
9. AC Voltage Selector – This 2-position switch sets the AC input voltage for the
speaker. US users should set this switch to "100-120V" whereas UK and most
European users will need to set this to "220-240V."
10. AC Input – This jack accepts standard 3-prong IEC power cables. Make sure
your AC Voltage Selector (see item #9 above) is set to the correct voltage for your
country.
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