BILL HOLLAND: Welcome back to Gearwire.Com. I'm here with the dbx 223 stereo two-way and mono three-way crossover. Crossovers are something a lot of people don't talk about, but if you're planning on throwing a party bigger than your family's election-day victory party, I suggest actually learning a little bit about crossovers and why we use them.

Most standard PA speakers you see like the JBLs that a lot of people have, they have passive crossovers built in. What a crossover does is it splits the individual frequency bands, like your highs and your lows for example. On a JBL, you might have the horn for the tweeter and the woofer, and what it'll do is split those bands and send them to the high and the low so you can optimize the highs and the lows depending how you need to. That's pretty much the foolproof way. If you don't know a lot about audio, allowing that to happen, a lot of times you'll see a bass response knob and a treble knob.

ow, what's the problem with that? Well the problem with that is that the passive crossover is reliant on your amp. It's reliant on the active -- either active power amp built into the speaker or the amps that are sending the power. The problem with that is you can often -- it causes problems where you're overdriving your speakers. The reason you're using an active crossover in larger systems or when you want to drive something harder is you want to have the most finite control you can have over your highs and your lows. So if you're playing at, let's say, House of Blues, House of Blues is going to have a crossover going to the low speakers, you know, the mids, the highs, especially in their case. They're going to have subs, they're going to have a low, they're going to have a treble, so they're probably going to have one of these for both the left and the right signals. Surround systems? I've never really worked with surround so I wouldn't know, but generally in a live environment, you're going to find that you're going to want to split the signal into your lows and your highs, and then divide that up between on a larger scale with your low mids, your high mids, and your sub-frequencies.

And this can actually be in mono mode. You can sum in a low frequency subwoofer. So let's say I want to use this as a mono, and for my left channel and then I want to have a right channel, the advantage to that is then my low and high knobs for the other side end up becoming my low mids and my high mids, and I have more control over different frequencies.

The disadvantage to an active crossover like this, however, though is that you're going to need a separate amp for every frequency. If you go to even school gymnasium where they'll have sound setups, you'll notice that there's a separate amp. Well, each amp feeds a different frequency of speaker, something to keep in mind when using an active crossover. This is not for a small setup if you're just doing a little, you know, boutique DJ gigs. This is for when you're dealing with serious sound for a serious space, you know, be it a stadium concert on an underground party of some sort somewhere. So let me get in close here, and I'll show you how this works.

Okay, so that here we have the front side. I've got my microphone going in through channel 1. So you'll see I have my input gain. I can turn that up and down. I have a low cut which will automatically cut off the very bottom end frequencies, so if you've got some booming, overwhelming bass, you can just roll it off right away, although just to note it is a little bit difficult to pop out but that's because you don't want that popping out on you by accident and then going, "Oh, why does it sound like that? Why is my bass way too big and distorted?"

Now I have my low/high control. Now, if you look here, there's two different readouts. The reason why is that the top one is for where we're in mono mode. When we're in mono mode, that indicates that we are also summing in a low-frequency subwoofer. Right now, I'm in stereo mode so that's why it's set up like that, so it's going to be my low/high control. And you can see I can cross over this way and go over this way, and you can hear the difference as I adjust the crossover.

Here we have our low output, and I can take that way down. You'll hear how that affects my voice, and then also high output where you can hear as my voice kind of reaches the inaudible frequency I'll just keep talking [INAUDIBLE] and then my voice comes back, and you can turn that all the way up and turn this down, and you can [INDISCERNIBLE] the low frequency of my voice. So you can see how it's adjusting the two separate frequencies. Now what I've done, I've sent my low output and my high output to my left and right channels of this Yamaha powered mixer right here, just to give you an idea of what you're hearing this through. I can also invert the signals, and you'll hear how that changes my voice as well. I'd invert it to high but not invert it to low, and now I've inverted the low but not inverted the high, so you can hear how that affects the sound as well.

Now, if I were to set this to mono mode, what would happen is I would have my input here low cut. This will become a low-mid control. This will be now low output. This would do nothing. Now I go over here, this becomes my mid-high, my mid output, and my high output. So the nice thing is that if you've got two of these, you can do a left and a right with more control. Again, fantastic, but you do need to make sure you have enough amplifiers to cover that. If you think about it that's three outputs times two, that's six. You need six high-powered amplifiers going into your speakers. This is for a serious setup. This would not be for your Average Joe playing at a high school party. This is the real deal. We're going to go to the back now, and I'm going to show you how to switch between the two different modes.

Okay, here's the back side. Now, I was talking about summing in a subwoofer. Well, what happened in that situation is you see I have my low sum control here. It says normal in sum. Push that in, and now I can feed my subwoofer right here. Turn it off back to normal, we're back in normal mode. You can see I can also switch between stereo and mono mode, and that's what allows me to do that right there. Now what I can also do is I mean I can just if it's just set to low, I can send out a low but the LF sum is what allows me to go to a _____0631 if I keep it normal, it's just going to send a normal low signal. Keep in mind as well when you're in mono mode, it can go either way. You'll see there's a backslash here, and it just says low LF sum. Pay attention to how everything's hooked up and make sure that it's either selected to normal or sum, summed again, going into subwoofer.

Now over here you'll see we have channel 2 and channel 1. When it's set up the way we normally have it set up, you have high, low, and input. On this side, you'll see I'm hooked into my input and then I have my low and my high going out to the powered mixer. Here we have a little high control. This is like just a pad. You can see how I used the pad and then I turned it back off, so I hope I haven't hurt anyone's ears when I did that. Then I switch over to mono mode here, and you'll see I have high, mid, and this is not used, so you won't be using that at all. This becomes my crossover frequency mid-high control. I can turn that on or off. Here, this is not used. I have my low, my low-mid crossover frequency, and my input. So again, two different ways to use the same active crossover, mono being a way to use it as a one channel for a left send and you can use another for a right send.

Well that was the dbx 223. My name is Bill Holland, and you're watching Gearwire.Com.