In-ear monitors are becoming more and more ubiquitous every day and wireless hardware systems are coming down in price, opening the market to a wide range of users, some fairly sophisticated about audio and other not so knowledgeable. In the hands of a trained pro monitor mixer who understands the needs and limitations of IEM systems (and users) the need for an in-line brick wall protection limiter may not be so important.
However, at any gig — at any level — stuff does happen, although hopefully less frequently as you get up the production food chain, but when a show is live, sometimes all bets are off. Examples of transient high-level audio glitches can include unexpected sound spikes that occur from microphone drops, audio feedback, incorrect volume settings, pulling the plug on a condenser mic when it’s powered up and any other sound hazards that may occur during a performance.
Unfortunately, when you’re wearing a set of in-ears, you may be guaranteed an up-close and personal front row seat to that spike or sudden sound blast, which is anything but pleasant. And that’s exactly what the Sound Guard from Ultimate Ears Pro is designed to protect from.
With the UE Pro Sound Guard, artists receive protection from unexpected sound spikes that occur from microphone drops, audio feedback, incorrect volume settings and other sound hazards that may occur while performing or recording. So far, so good; but there’s more going on here.
Matching impedance of balanced armatures with multi-way crossovers can be complex and certain personal monitoring/mixing systems don’t handle such IEM designs — from any manufacturer — very well. Beyond its protection duties, Sound Guard also functions as an audio buffer that provides variable impedance matching from the source device to your balanced armature IEM earpieces (such as the UE Pro line) for enhanced dynamic range and improved sound quality. And although Sound Guard is intended specifically for those UE Pro IEM’s, it can function with any balanced armature design.
The System
Housed in a compact 2-by-2-inch plastic box that’s about a half-inch thick, the Sound Guard definitely gets points for being compact. There are two 1/8-inch stereo TRS jacks (input and output) on either side of the unit, which connect in-line via an included 6-inch TRS patch cable to your IEM receiver (or hardwire personal mixer), with the output jack going to your earpieces. The Sound Guard box has a recessed on/off switch and two LED’s to indicate power-on and battery condition.
Speaking of batteries, the Sound Guard is powered via two onboard 3-volt CR-2450 lithium cells. Unlike the more common CR-2032 button cells used in most clip-on guitar tuners these days, the CR-2450’s aren’t terribly common. The circuitry requires six volts to operate; alternatively, it could have been designed to run off four AAA cells, which would have substantially increased the unit’s size and weight. On the plus side, Sound Guard ships with two sets of batteries and the CR-2450 batteries last for a respectable 20 hours.
The rear of the box has a removable battery compartment cover and two threaded holes that accommodate an included belt clip mount, which can make access to the batteries somewhat tricky, although the belt clip can securely hold the Sound Guard in a convenient location next to the IEM receiver — on a pocket, belt or guitar strap.
Plug and Go
Operation is pretty simple. Since the Sound Guard operates as an in-line, unity gain device, it’s pretty much plug and go. However it’s suggested that you first connect the components (receiver and Sound Guard), power up the Sound Guard, and then slowly raise the receiver’s playback level to a comfortable listening level.
It should be emphasized that while the Sound Guard is optimized — and can provide very good results with — UE Pro UE 900s and custom UE Pro IEM’s and other balanced armature designs, use of this product with single-way dynamic headphones or IEM’s is not recommended.
So besides operating as a variable impedance matcher for balanced armature headphones, Sound Guard includes a very effective brickwall limiter. The latter kicks in to offer hearing protection when the preset threshold is exceeded, typically by some kind of transient. There’s no user control over the threshold point, which makes it very easy to set up and operate; however, it kicks in somewhere in the range of 107 dB, which may be too low for some users who really like it loud, or are listening to mixes with an extremely wide dynamic range, where false triggering may occur.
Currently, UE Pro is considering making a version of Sound Guard, possibly with several switchable protection threshold presets selected for the user’s listening preferences. But for those who listen at a more reasonable level, any lack of user threshold control will not be an issue. In such cases, this opens the listener to really appreciate the benefits of the impedance matching circuitry and the Sound Guard’s wide (and quite clean) 20 Hz to 20k Hz response, along with automated sound level management to offer effective protection from unanticipated loud and accidental audio spikes. And that can be a good thing.
At a Glance
Blunting the Spikes
The Ultimate Ears Pro Sound Guard is a compact, easy to use, in-line/in-ear processor designed to offer automated sound level management and spike protection combined with impedance matching circuitry to optimize the performance of balanced armature in-ear monitors.
UE Pro Sound Guard
PROS
• Simple operation
• Effective protection from unwanted spikes
• Onboard impedance matching for balanced armature IEM’s
• Lightweight, compact
CONS
• Not recommended for dynamic IEM’s
• Batteries may be difficult to source
• Limiter may kick in at higher than moderate levels.
MSRP: $199
More Info: http://pro.ultimateears.com
