Invariably, someone suggests hiring radio mikes - one per child and the problem is solved - easy eh? Well, not really as there are two things working against you - one of them is cost (and we're not going to talk over the why's and wherefores of that here - you can ring us when you're sat down in a comfy chair!) the other is the simple practicalities. Radio mikes being operated using electricity (in simple terms) are governed mostly by the pesky laws of physics and radio waves - yes there are digital systems available but not in the practical price range we're working in - which dictate how many microphones can be used simultaneously. Alongside the laws of physics sit the laws of the land which dictate where in the radio frequencies you can legally use radio microphones - it's all changed over the last 2 years to make room for mobile broadband (and rumour has it - is going to change again) which has had some impact on what you can use.
The Hardware
Central Theatre Supplies is a longstanding Audio Technica user and dealer - we install a lot of their microphones (wired and wireless) and also use their equipment for our hire stock. The AT3000 series is sturdy and reliable kit and priced at the point where we can hire it out sensibly and still make some money from the hires. There are other makes of radio mikes available which we do use and install - JTS mostly and some makes that we have hired in from elsewhere to cover busy periods. The make of the radio microphone determines how many you can actually use simultaneously, it's to do with design of the circuits inside the transmitters and receivers that help the manufacturer reach the performance criteria they set themselves. The AT3000 series working in Channel 38 (the licensed frequency in the UK) generally allows us to use 10 units simultaneously - so if you have 8 performers that you can't hear it's quite simple or even if you find a couple more that are just on the edge of being intelligible. The problems arise when you suddenly realise that you have 12 performers who can't be heard - what do you do then?The Plot thickens
The first reaction when usually being faced with performers that can't be heard is "Oh - put a radio mike on them..." and for 3 or 4 that works as an approach (there may still be issues that even with a radio mike the performer may still not be heard - if they're not trying to 'project' the microphone won't pick up much of a signal). As we noted above, if you think you need more than 10 performers with mikes - then there are issues to be confronted.- Is everyone on stage simultaneously? Whilst you may have 18 performers that can't be heard clearly - are they all onstage together? It might be that with some thought, you could share 6 microphones (or less) between them by having a member of staff backstage helping the performers to swap microphones with each other.
- How long are they onstage? This is linked to the previous question - if the performer is singing one song and can't be heard, does it make sense to put a microphone on them? Does the blocking of the show allow them to be placed onstage in a position where they could be picked up with a conventional (and cheaper) corded microphone? Would it not be possible to do that over more of the show - use some radio microphones and some strategically placed corded microphones? Not sure about how to handle teaching projection? Have a look here
- Will your sound system handle 8 more microphones? This is (believe it or not) the most common stumbling block that we come across. Most schools nowadays have a projector and screen in the hall with some means of plugging in a laptop to play music - some schools have an actual sound system, whilst some (and it's shrinking) still have a Coomber Portable PA. To use radio microphones, you need one input channel per microphone so for 10 - that's 10 channels of mixing AND someone who can sit with the mixer during the performance fading microphones up and down. Don't listen to the folk who say "Oh no - we just turn them on and leave them..." - they've never heard the apocryphal story about Barbara Windsor in the first West End show to use Radio Microphones!!