IEM Tips for the field
In-Ear Monitor(IEM), Interruptible Fold Back(IFB), or sometimes simply referred to as "Ears", are one of the most powerful and useful tools available and the least understood. Think of IEM as simply a wireless mic system running backwards. Instead of the talent using a transmitter on stage to send a signal to a receiver mounted in a rack, an IEM has a transmitter mounted in a rack and sends a signal to the talent on stage.
There are a couple of rules to keep in mind that will make the IEM system work efficiently and minimize interference to the wireless mics on stage:
First, Use the Scan feature! After allocating the wireless mic frequencies turn on all the microphone transmitters. Now take an IEM receiver pack and perform a scan (see below for full scanning instructions) on the stage where the receiver will be used. The scan will go through all of the frequency presets looking for available frequencies. Even though it may be only 50 or 75 feet between Front of House and the stage, or even less to Monitor world where the IEM transmitters might be located, it is important to find the best open frequencies available. You will be surprised by what might show up like TV stations or other interference!
Second, Frequency band separation. The goal is to group the IEM frequencies so that they are at least 8 MHz away from the nearest wireless mic frequency. This gives the receivers a chance to effectively filter out the IEM signals, maintain good sensitivity and reliability.
Third, if at all possible, use an external antenna! This will give you the best range and performance. If you can't use an external antenna, move the IEM transmitter as far away from the wireless mic receivers as practical and close to the performance area. If you have more than two IEM transmitters, always use a combiner like the AC3/NT to avoid intermodulation of the transmitters. When using an external antenna for the IEM, placement can help save a lot of grief. Getting physical space ( at least 8 ft if possible) between the wireless mic receive antennas and the IEM transmit antenna minimizes intermodulation effects and helps the wireless mic receivers to be as sensitive as possible which prevents drop-outs
SR 300 IEM system setup: Utilizing the scan feature
- Before you do a scan with your EK300 or EK2000 receiver, turn ALL of your IEM transmitters ON!
- On your TX, select EASY SETUP (and leave it there).
(This does two things: 1) It automatically mutes the RF on your TX so your RX doesn't see it when scanning, and 2) it puts the TX in "receive mode" which is the next step in syncing your TX from your RX)
- With your RX, scroll to EASY SETUP >>>SCAN NEW LIST.
- Select SCAN NEW LIST
- The Bank with the most available channels will be displayed (i.e.; Bank 17, Free 8)
- Hit SET button and the first available channel in that bank will be chosen.
DON'T PRESS ANYTHING ELSE!
SYNCING BETWEEN RECEIVER AND TRANSMITTER
- Once you've scanned and found the best bank/channel configuration, hold the RX IR near the TX IR and the SYNC should quickly show a check mark.
- Proceed to the next TX and hold up the RX IR near that TX's IR and that will SYNC to the next available channel in that bank!
- Continue doing the same with all TX's in the rack.
- STORE THE SELECTED BANK/CHANNEL(S) BY PRESSING THE <> KNOB ON EACH TX!!!
SYNCING BETWEEN TRANSMITTER AND RECEIVER
Once you've sync'd your TX's from the one RX (that performed the scan), then it's time to sync your other bodypack RX's to their respective TX's.
- Turn each bodypack RX on.
- Hold each RX near its TX's IR window and press SYNC on the TX. As soon as you see the check mark, this RX has been sync'd to its TX's Bank/Channel.
- Continue the same process with each respective RX and it's corresponding TX.
Your IEM configuration should now be complete with all TX's transmitting on different (available) frequencies, all within the same bank!