Hollywood 24CX-2 Manuale Utente

© 2003 TDM Audio, Inc. 

Electronic Crossover Owner’s Manual 

Page 5 

Signal 

Source

Power 

Amplifier

Low Transducer

Mid Transducer High Transducer

Passive 

Crossover

This kind of crossover is called a passive crossover because it does not use any power other than 
the power contained in the signal to accomplish its task. Passive crossovers have certain 
limitations that make them inappropriate for large systems, or systems requiring high fidelity at 
high sound pressure levels. Some of these limitations are… 

•  Insertion Loss: Some power is lost in the crossover network which lowers the efficiency 

of the system. 

•  Power Handling: Passive crossovers that can handle more than a few hundred watts 

require very large, very costly components. This makes them impractical for high-power 
systems. 

•  Fidelity: The nature of the way passive crossovers work makes it difficult to design them 

with high fidelity in mind. The kinds of components used in passive crossovers tend to 
color the sound in undesirable ways. 

To get beyond these limitations, large systems, or medium sized systems that require high 
fidelity incorporate active crossovers. TDM 24CX series crossovers are active crossovers. These 
crossovers are not usually housed in the speaker cabinet. They are separate units that are usually 
mounted in a rack with the power amplifiers. They are called active  crossovers because they 
require power in addition to their input signal to carry out their task. Active crossovers are 
different from passive crossovers in many ways. Here are the key differences… 

•  Line Level Signals: Active crossovers work with the line level signal before it reaches 

the power amplifier. This allows them to use smaller, better components and designs.