I had a really interesting conversation with a customer the other day about his live rig. He was using a Yamaha StagePAs system, which uses a small powered mixer / amplifier and passive speakers, but wanted to get something a bit bigger.
In an ideal world, I think he would have liked to have a mixer with more channels, say between 8 and 12 stereo / XLR with separate USB or auxiliary channels for backing etc but retain the Yamaha speakers. In principle, there is nothing wrong with that idea, however, the speakers present a problem: they are powered by the mixer he wanted to replace. In order to keep them, he would need to either:
- Buy another mixer amplifier, or
- Buy a passive mixer and separate amplifier.
As we were chatting, it transpired that he already owned a 1000W powered cab that he was using as a monitor. This cab alone had more headroom than the entire Yamaha StagePAs. If he had another, he could have the option of using a passive mixer (which tend to be cheaper) and it would solve the mixer amp / mixer + amp problem. So, the solution presented itself.
Which To Go For?
So are powered cabs better than passive speakers? I certainly feel that they offer huge flexibility for a live performer. You are able to amplify your sound simply and you can set the headroom on the cab itself without concerning yourself with the output of your amplifier. On the downside, they are heavier and require power to both sides of the stage but I feel the benefits outweigh the costs.
What about passive speakers? Well, if you are using a mixer amplifier you don’t need to worry about power to the cabs and it is simply a matter of ensuring that you speakers have enough headroom to deal with the amplifier. For example, if your mixer amp kicks out 1000W but you only have 100W speakers, you have a problem! Divide the amplifier’s output by two and you will need a minimum speaker wattage of 500W per channel (I’d go for a bit more for safety’s sake).
When I started out, back in the late 80s, the band I worked with always used a passive, analogue mixer, with a separate amplifier driving the two front of house PA speakers. Frankly, there was nothing wrong with that set-up and, to a large extent, there still isn't. However, at the time, there really wasn't another option. As technology has moved on, it has given us more options. The wrong option is the one that doesn't work for you or in the situation. The band I'm in currently uses a passive mixer and powered cabs. We can scale it up or down as required and it means we can play in more places as a result.