Join Brent Carpenter for an in-depth discussion in this video Scanning frequencies and configuring the RF antenna for wireless in-ear monitors, part of Live Sound Engineering Techniques: On Tour with Rush.
We are using the Shure PSM 1000 monitor system. What's really nice about the Shure system is with the combiner and with the transmittor, you can also get a separate piece of software. That through networking let you change your frequencies and it will do all the calculations for you. So you can lessen the chances of having an interference problem during the show.
So how do we do that? Well we start by opening the software and we can see these lines represent the frequencies that we used at the last show. We have just started a new show, so we're staring brand new on the day. Now we are in Denver today. So I can go in through changed TV channels. And I tell it that I am in postal code 80204, and I hit Search, and it tells me it found it. It knows where we are, we're going to save it. And it is telling me, all these big red sections are the local tv stations.
It doesn't necessarily mean that there's a radio frequency coming out of that tv station, because a lot of tv stations are cable only. We don't have enough information yet to be sure that we're going to have a perfectly clear radio frequency day. I look at the Analyze button, and it tells me all, all my ear monitors are green. That's a good thing. So we're starting good. Now what I want to do, is I want to tell it stuff that I know. My guitar tech on the other side of the stage, uses a certain frequency band and I know he needs to use that certain frequency band. So I can go in and I can tell it to import.
The information I've already put in, so now I've just told the computer, this frequency band, which is 655 to 682, I don't want anything in there. Just exclude those automatically, and we'll save that. Now what we have to do is we have to find out if there's anything in the building, any atmosphere, any, any radio frequencies, maybe the building has a a hearing assist feed. Maybe they've got radios. They've got just to find out what's going on in the building the environment we call it, to see what's happening.
So I'm going to make sure all of my radios are off. They are off right now. I'm not transmitting anything, and I'm going to run a scan. The bell pack is scanning all the frequencies that it uses which this bell pack uses between 626 megahertz and 698 megahertz. So it's going from 626 and just looking and seeing what's in the air. So lets find out what's in the air. So we are going to sync it back to the unit. And then, now we have to tell the computer To go get that information. So we're going to change the scan data, we tell it where to go get it, and there's our first scan.
And as we can now see, we're going to make that orange because it's easier to see. We can now see, that here's the TV stations, the red, and there's really nothing. Anywhere that's going to affect me. We can zoom in really close so we can take another look at it. There we go. We see that everything here is really, really low. This could just be hash, that's coming from halogen lights or a balast from one of the lights in the air or a video screen. So this doesn't affect me at all. So I'm Pretty sure I'm going to be clean. So now what I want to do is I want to turn my units back on.
And I'm going to run another scan, and a lot of people don't do this. I do it because it gives me a visual on the screen. That way I can make sure that I'm not sending out radio frequency noise that other people might have to deal with. So now I'm going to go back. And I'm going to do another sync because I've done a new scan with my belt pack. And we'll import it back into the computer. And we'll make that purple. So now I can look at this and I can get exactly what frequencies I'm creating and transmitting and that's that.
Now using this computer program and this system makes it really, really easy. I can do this in four or five minutes. If you don't have this kind of system, every major company that comes out with a belt pack system, they offer a system in their belt pack called groups and channels. If you've got multiple radio frequency things happening at the same time, always be aware of your group. The groups are made to work within each other. So group one channel one, and group one channel two, and group one channel three are all made to work together.
They have somebody somewhere with a computer, has figured out that these frequencies will work together without causing interference on each other. It doesn't mean you want to have interference from something in your environment, but you will not have problems inside of your own groupings. Even if you're in the same group, and one of you recognizes that there is a problem, there is a radio frequency issue, don't just switch groups, stay inside in the group and go to a different channel inside the group. Most of them offer between 12 and 15 channels inside of a group. And there's some that offer it as high as 20.
So there should be plenty of room for, for you to find a frequency that will work.
- Choosing the PA for the venue
- Setting up points, motors and cables, and trusses
- Getting the best use of both analog and digital signal paths
- How Rush gets that Geddy, Alex, and Neil live sound
- Setting up the digital monitor mix console
- Doing the line check and sound check
- Using audience microphones to connect the band to their fans
- Getting even coverage in a large arena
- Working the monitor console and the power of snapshots
- Loading out of the venue