BSS Audio FDS-318 Owner's Manual User Manual
Page 6
6
2.0
The difference between Active and
Passive Crossovers
Passive crossovers divide the frequency spectrum after the signal has been
raised to a high power level. They are generally heavy, bulky and inefficient.
Active crossovers utilise ICs and transistors, and divide the frequency spectrum
at line levels immediately ahead of the amplifiers (See Figure 2.1). An active
crossover does the same job as a passive crossover, but with more precision,
flexibility, efficiency, and quality.
Fig 2.1
Active and Passive Crossovers
Some advantages of active crossovers are:
• Crossover frequencies can be more readily altered to suit different driver-
horn combinations.
• The level balance between the 2 or 3 frequency bands (brought on by
differences in driver and amplifier sensitivity) can be readily trimmed.
• Inside an active crossover unit, line-driving, signal summing, driver
equalisation, system muting and polarity ('phase') reversal facilities can all be
incorporated at small extra cost.