Article courtesy of "Technologies for Worship", May/June
In-Ear Monitors for Worship?
by Kent Margraves
What are in-ear monitors (IEMs)? Most of us have attended a
live event or viewed a broadcast program in which we have seen artists
wearing these small earphones. Why? What exactly are they hearing?
How do they work?
There are a variety of types and styles of these "ear buds"
on the market today, but the basic concept is consistent. They are
used for the purpose of providing the "talent" with their
audio monitor signal directly in their ear, or ears, rather than
via traditional loudspeaker wedges on stage. Conventional circumaural/supraural
headphones are too bulky and distracting for live performance, and
professional ear buds are actually designed to fit into the ear,
like an earplug. But, what are the advantages/disadvantages of this
method of audio monitoring, and how can this technique be effectively
employed in live sound for worship environments?
the most important benefit I have encountered when using in-ear
monitoring systems on church auditorium stages is the potential
for much lower stage volume. Since fewer monitor speakers are needed
on the platform area (in some cases, none) the overall SPL level
on stage may be considerably less. This means a cleaner, more intelligible
house audio mix (especially in the front few audience rows) and
far less acoustic leakage into any open mics on stage. And, of course,
lower levels on stage means less chance for acoustic feedback! Furthermore,
any audio recording that is being done will be dramatically improved.
Mobility is another point where ear monitors prevail, at least
the wireless type. A performer who employs ear buds quickly finds
that he/she is free to move about with virtually no change in the
sound they hear - it travels with them! There is no longer a need
to be concerned with standing right in front of a wedge monitor(s)
or worry about stepping into the "sweet spot". And the
artist enjoys a volume control at their fingertips.
Hearing conservation is an ever-growing concern, and as IEMs require
much lower SPLs than typical loudspeaker monitors, they are clearly
safer for the human ear. Plenty of audiology experts recommend this
method of monitoring over loudspeakers. (The IEM models from Sennheiser
and several other manufacturers employ built-in limiters to aid
in preventing dangerous levels).
And my favorite advantage
.discrete communication! How many
of "us audio mixers" have experienced the situation during
a worship service where we desperately need to get the attention
of someone on the platform who, despite your best arm-waving efforts,
seems to look everywhere in the auditorium except at you? Ever consider
trying to whisper through a "talkback" function modestly
through stage monitors, guessing how much level is enough to get
the person's attention, but not so much that you are heard in the
first five rows of the audience area? Well, with ear buds we have
direct access to the ears of the talent wearing them - and there
is no need to worry about spill or leakage. In fact, broadcasters
have used ear buds for many years for monitoring and talkback feeds
in a similar way. They call them IFBs (Interruptible Fold Back),
are typically mono and not always of a fidelity suitable for music
So how do IEMs really work? They can be wired or wireless. Most
available ear buds are terminated in a common "mini" headphone
plug, which can be driven from most any device with a headphone
output. Wired versions are often used for stationary performers
(drummers, for instance). The wireless type (our focus here) requires
the artist to wear a beltpack receiver with stereo headphone output.
In this case, an offstage wireless transmitter is necessary. Hence,
a true wireless inear monitor "system" consists of a transmitter,
a portable receiver, and ear buds. The wireless format is commonly
RF (radio frequency FM) and can be loosely envisioned as a "backwards"
wireless mic system - that is, instead of the talent transmitting
their wireless audio to an off-stage receiver, an off-stage transmitter
broadcasts the applied audio signal to an FM receiver worn by the
talent. In fact, at Sennheiser we manufacture two models of wireless
in-ear monitor systems that basically employ the same RF wireless
design techniques that drive our award-winning wireless microphone
products (however, these IEMs transmit two channels rather than
just one mic signal). This means that these systems employ extreme
RF frequency agility - the ability to quickly retune to a wide choice
of UHF frequencies to ensure interference-free operation. The same
features/benefits you would expect in selecting a quality RF wireless
mic system should also be demanded for any wireless in-ear monitor
system being considered (frequency agility, RF power, S/N ratio,
broad audio frequency response, etc.). But remember, RF wireless
IEMs compete with RF wireless microphone systems and any other local
RF, and must be frequency coordinated in the same manner used for
RF wireless microphones.
Most models marketed today are dual channel. The transmitters have
two audio inputs, which can be run in stereo, single mono, or dual
mono. The monitor signal to be heard via the in-ear system would
be the same signal used to feed a monitor power amplifier (and its
associated processing gear) in a traditional wedge monitoring setup.
This signal might be derived from the house console's auxiliary
buss(s), from an on-stage dedicated monitor mixing console in more
complex setups, or even an output of one of the specialized monitor
matrix systems arriving on the market these days. Either way, any
line signal that would work for feeding a monitor send on stage
would be suitable, theoretically, for use with an IEM system.
the mix must be different. Wouldn't it be wonderful if we could
literally replace our monitor sends on stage with an in-ear system
and do nothing else? Unfortunately, the signal going into a performer's
ear via buds often needs to be quite different than what would work
in a wedge.
Certainly all ear buds, to varying degrees, offer acoustic isolation
from outside sounds, almost acting like earplugs. This can be great
- or disastrous! Consider, say, a music minister in a common worship
service environment that has just made the change to wireless in-ear
monitors, for greater mobility and lower stage volume, etc. Since
he is now acoustically isolated by the ear buds from surrounding
sounds he must rely nearly 100% on the IEM mix for what he is hearing
- he no longer has the benefit of the acoustics of the venue and
the ability to hear congregational singing or other sounds naturally
- big problem, right?
This is why many well-applied IEM setups now require audio engineers
to provide audience response microphone(s) or other elements to
be mixed back in to the IEM send. In this way, the acoustic sense
of the "room" can be returned to the above music minister's
ears and eliminate the panic he might have first experienced with
the buds - feeling very alone and isolated
involved in properly "returning" the feel of the room
to in-ear monitors and the associated issues of stereo imaging are
quite complex and certainly a sizable study in themselves. And,
from what I have seen, these practices are largely still being molded
and defined in the pro audio industry).
Another approach is to wear only one earbud, leaving one ear open
to hear the natural environment. Case in point - Jonathon Lowery,
Associate Minister of Music at Hickory Grove Baptist Church recently
began using a Sennheiser 300IEM wireless in-ear monitor system in
mono mode. He has settled on the one-ear approach and states, "Being
a hearing impaired vocalist/worship leader, my ear monitor system
has proven to be an absolute lifesaver. No matter where I stand
or turn on the platform I always get a clean, tight mix of the "essentials"
in one ear, and I keep my other ear open to hear the congregation
and orchestra, and that helps me stay in touch with the general
feel and mood of the service. What an awesome tool!".
believe this approach probably makes more sense to many church musicians
and may take the fear out of attempting to "switch to ears"
from those trusty old stage monitors.
As mono, single channel monitor mixes are the most common type
and are certainly appropriate for many stage applications, the "stereo"
ability of many IEM systems might, at first, seem useless. But,
several manufacturers offer creative ways of using the second audio
channel feed in an interesting way other than "traditional
stereo". A common approach is to build the beltpack receiver
with the ability to mix the two available signals in dual mono -
almost like a portable two-channel mono mixer. If then, the transmitter
gets its monitor mix on one input and the talent's audio (his/her
instrument or voice) on its other input channel that talent has
then the opportunity to balance - in their own ears - the level
of themselves against the rest of the mix by via the panning knob
on their beltpack. At Sennheiser, we term this feature "Focus
Mode". But, now what will all those church sound engineers
do all day when they don't have to repeatedly respond to "More
of me in the monitor, please!"
If you are involved in a church sound or music environment and
are thinking about the potential of moving to in-ear monitors you
will want to compare costs. Prices vary widely, but there are several
high-performance wireless models currently available on the market
under $1000 per complete system. Not a hard sell to any finance
committee when compared to the cost of traditional stage monitoring
gear (power amplifier, loudspeaker wedge(s), and equalizer or other
processors). And, the sonic fidelity from well-designed models can
be astounding. Also, keep in mind that any number of receivers can
be added to receive the broadcast from a single IEM transmitter.
Some systems come with adequate, high performance ear buds and some
may require 3rd party specialized ear buds purchased separately
for optimum performance. Additionally, anyone who is planning to
wear ear buds for any real length of time should consider having
custom receiver molds made. These are silicon fittings that can
be customized to exactly fit one's ear and provide increased comfort
and sonic performance, especially during long sessions of wear.
Any licensed audiologist should be able to quickly form the impressions
of one's ears (it's quick and painless) and forward them to a specialty
house to have the final custom silicon fittings produced. This service
is typically $100-$150, and is well worth the investment.
Finally, IEM systems are not right for every monitoring situation.
But, they are increasingly common and can offer many sonic, financial,
and health benefits. This rapidly growing audio trend is intriguing
and is worth fair consideration for any worship facility reviewing
their sound monitoring options.
View the original article from Technologies
for Worship Magazine.