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FEATURE demanding artists in the world, will conďŹ rm that a properly designed IEM can deliver full ďŹ delity with just two or three drivers, preferably with only one crossover to minimise phase distortion. Excessive drivers are certainly louder, usually more expensive, and provide more parts that can break down. “Sensaphonics IEMs are designed for deep insertion – past the second bend of the ear canal – and are made from exible medical-grade silicone, which has been proven to provide more isolation than other materials. Because the ear canal changes shape with facial movement, silicone earpieces move with them, maintaining the seal. An acrylic earphone that ‘pops right in’ may be convenient, but is poorly ďŹ tted and will not reliably provide the needed isolation and seal on stage. “This is important because losing the seal results in a huge loss of bass response (often the cause of artists pulling one earphone out). Hard acrylic cannot reliably maintain its seal under stage conditions, which is one reason so many manufacturers keep adding more drivers. Beyond the marketing advantages, in my view, it’s also an attempt to compensate for a design aw. “Soft silicone also provides a more comfortable IEM experience, which is very important for musicians and sound engineers who regularly deal with long rehearsals and performances.â€? Mick Shepherd advises against buying an IEM system that operates on a frequency above 694mHz as there’s a very good chance that availability in that spectrum for radio mic and in-ear users will disappear within the next ďŹ ve years or so. “Look for a system with a solid body pack as they often get dropped. A good wide switching window to maximise frequency choice is advisable for European and worldwide use,â€? he says. “The ability to accept two mono inputs at the transmitter and mix them at the pack is very useful – it allows you to get two discreet mixes from one transmitter and two packs. “If you don’t move around in performance (eg, most drummers) look at a hardwire system – much less expensive. Again look for the facility to mix two mono inputs – you can run a click track separately this way.â€?


February 2015

ProGuard IEMs from Sensorcom Tolonen cautions: “Ensure you get the right system for your application. If you are a global touring act, the tuning bandwidth can be a factor in making sure you have enough of a ‘window’ to get all your channels programmed as spectrum will change from country to country.�

       “DeďŹ nitely,â€? declares Shepherd. “We wouldn’t have cheap systems in our hire stock and on the odd occasion that we’ve sold them we’ve had nothing but trouble. If you have a limited budget it’s worth

looking for ‘pre-owned’ decent quality systems in good condition.

monitors as acoustic feedback is not a concern. But like most things in life you

“It depends what you consider cheap,â€? says Tolonen. “The bottom line is that your IEM system is what you listen to when you are performing. It needs to sound good, needs to have solid RF performance and also have a feature set that suits your requirements. I’ve heard on several occasions that a good IEM system can make you perform better so it’s critical you get the right one for the job.â€? Frankson adds: “Even cheap monitors will produce better monitoring than oor

will very much get what you pay for and with well-built IEMs with MA drivers the sound will create a sense of precision and detail which will make them more pleasant to listen to.â€? “Sound is very subjective and you like what you like – the real answer is ďŹ nding the right balance in quality and the sound you desire rather than cost,â€? says Piddington, while Santucci concludes: “For professional musicians on stage, there is no substitute for quality.â€?

     Sennheiser was among the ďŹ rst companies to launch wireless in-ear monitoring systems. After a period of time when the company supplied individually manufactured systems to artists, Sennheiser eventually launched its ďŹ rst professional in-ear monitoring series in 1996. These systems largely corresponded to the current state of the art. “However, since then we have seen quite a few improvements regarding the convenience of IEM systems, and product features have been continually reďŹ ned to make the work of monitoring engineers easier,â€? says Martin Fischer, product manager, Live Performance and Music. “To further improve transmission reliability, for example, Sennheiser introduced diversity reception with its evolution wireless 300 IEM G3 systems and the 2000 IEM Series in 2009. Or take the Engineer Mode, which was launched a little later and enables the monitor engineer to tune into the

beltpacks of the artists and listen to their monitoring signals. “Then on the software side and via the Wireless Systems Manager Software, we created a remotely controllable RF co-ordination tool and included adjustable audio settings for IEM systems. Thus, frequency co-ordination of multiple monitoring systems has become a lot easier, while the audio settings ensure that artists get exactly the kind of audio reproduction they need and want.� On the viability of digital IEM systems, Fischer states: “Quite a few people are asking about digital IEM systems these days but such systems are currently not feasible because digital systems always involve a certain amount of latency due to A-D conversion and the codec used. “The requirements on IEMs regarding latency are quite high – if the signals travel too slowly, the IEM audio signal and the bone-conducted audio signal will interfere, and frequencies will cancel each other out. As a general rule,

the audio signal should not travel more than ďŹ ve milliseconds across the entire signal chain, (ie from the microphone to the monitor desk and back again to the artist.) At any point in this chain, any digital equipment will add latency to the signal.â€? Fischer suggests: “The most important criterion is transmission reliability. An artist relies on the monitoring, and a signal loss would be critical. Audio quality is also high up on the list, and most often a stereo signal is preferred over a mono one. “Also, many users ask for high levels, which can be attributed to the fact that many people only switch from wedges to wireless monitoring when they notice that their hearing has already deteriorated. “And last but not least, frequency exibility is becoming increasingly important these days. Frequencyagile systems allow users to select alternative frequencies should any given frequency band be congested.â€?

AMI February 2015 Digital  
AMI February 2015 Digital