formats

A case for passive stage monitors

I’m not sure I’ve ever seen a band rider that doesn’t state, “NO PASSIVE WEDGES”. Option B? “BIAMPED WEDGES”.

A passive speaker is one that has an internal crossover. With a biamped speaker you perform the crossover filtering before the amp channels.

In theory, a biamped speaker can provide superior sound. With a passive crossover, you’re losing power passing through the passive crossover network. With a biamped speaker, each transducer can be fed straight from the amp.

So biamped is more efficient as a concept but in this day and age of cheap & high quality power amps, I’m not sure efficiency is a concern.

I would guess that a biamped speaker can probably get louder than it’s passive counterpart but not sure that is actually the case.

Passive or Biamped?

Based on my experiences with biamped stage monitors, I would have to assume that very few sound companies know how to biamp a stage monitor correctly. If I had a dollar for every time a set of biamped speakers sounded completely different, I’d be retired by now.

The principles behind building a passive crossover network are well known & any decent speaker designer can do it.
This means that while a speaker with a passive crossover network might be limited in some ways, a batch of fully functional passive stage monitors should all sound the same. If the speakers haven’t been serviced incorrectly, the phase of all the transducers should be correct.

With biamped wedges there are many points along the signal path for things to go wrong. There are (4) conductors between the amps and the speaker. The active crossover points themselves can be wrong. The levels between the amp channels can be wrong which changes the crossover point & the sound of the stage monitor.

When I see a local monitor engineer adjusting the balance between the woofer & the tweeter at the amp, I know something is wrong.

For a stage monitor sitting on the floor, there should be no guess work involved with crossover points & transducer levels & they should all be the same. Any discrepancy should be adjusted somewhere upstream of the crossover & amp.