One of the most challenging situations in the world of live sound has to be a musician with hearing loss. Not only does the loss prevent one from enjoying music with its proper full-range response, but for some, hearing issues profoundly affect their ability to perform live on stage.
For these musicians, reduced ability to hear certain frequency ranges amid the cacophony of a typical stage makes live performance nearly impossible. For many, hearing aids are not a viable solution. They don’t provide full-range response, and lack the SPL handling, dynamics and control that a performing musician needs. Today’s most advanced hearing aids roll off the low frequencies below around 150-200 Hz, and only a few extend as high 10 kHz on the upper end. They are simply not designed to work optimally in a musical context.
The Sensaphonics AARO 3D system is comprised of an interface/control module and custom-molded earphones (the small white circle at bottom of the 3D-2q ambient earphones shown is the ambient microphone location). With properly fitted in-ear monitors (IEMs) and access to a dedicated monitor engineer with powerful mixing consoles and effects, touring professionals can stay in the game much longer. But for those playing small venues without dedicated monitor systems, hearing loss remains a huge barrier to playing.
Today’s technology, properly deployed, can help. Founded by an audiologist, Dr. Michael Santucci, Sensaphonics is dedicated to developing the products and expertise to help musicians retain their hearing health. Larry Revit, president and founder of Vermont-based Revitronix, is a performing artist with severe hearing loss. He is also both an experienced sound engineer and a research audiologist. This combination put Revit into a unique position to solve his onstage hearing problem using patented technology from Sensaphonics.
Revit designed a system he calls the Personal Sound System-3D (PSS-3D), based around the Sensaphonics 3D AARO in-ear system, along with a small array of outboard gear that includes two small analog mixers and a multi-function DSP device. The 3D AARO incorporates Active Ambient technology to provide full-range pickup of ambient stage sounds through custom miniature microphones embedded in custom-fit silicone earpieces.
Having on-board ambient microphones addresses the needs of a hearing-impaired musician by reducing the need for stage miking and enabling conversations between songs. Better yet, the binaural mics also retain full directional cues and can withstand on-stage transients of 140 dB SPL without distortion.
To compensate for the user’s specific hearing loss (Revit’s is down 85 dB or more in the high frequencies), the audio is routed to a simple yet sophisticated system of outboard gear for compression, EQ and mixing. This is accomplished through the Record Out jack found on the 3D AARO’s bodypack mixer. The Record Out function, designed to capture live binaural recordings, is used to send the stereo feed from the 3D ambient mics to a small outboard mixer.
At the mixer, the binaural ambience is combined with the console mix and, optionally, stage mics. The mixer is used primarily for supplemental preamplification of the ambient mic signals (panned fully left and right) with the other feeds. Ambience can also be equalized for optimizing the pre-DSP perceived response, such as reducing low frequencies when the user is stationed near a bass amp on stage. Once the inputs are equalized individually for tone and level, the resulting mix is sent to a multi-function DSP device.
The DSP device in the system delivers further adjustments to the stereo mix, starting with its 31-band graphic EQ, used to create a transparent tonality to the ambient mix. If needed, the audio is then further adjusted via a 5-band parametric EQ. This latter step was initially used to notch out frequencies that caused feedback, but proved unnecessary with the strong, persistent isolation (up to -37 dB) from the 3D system’s custom-fit silicone earpieces.
Additional DSP adjustments include a compressor, used to keep output levels within a convenient operating range; and a fast-acting peak limiter to eliminate clipping (and ear overload) on extreme transients. The final step of the DSP process is dynamic equalization (DEQ). For instance, in bass-heavy environments, Revit reduces low-frequency gain at high levels.
The last piece of the outboard signal chain is a second small mixer, which provides final balancing of the left and right mix for overall gain before returning the signal to the 3D AARO system via the bodypack’s unbalanced monitor input jack. Final EQ can also be added at this stage.
In normal operation of the 3D AARO bodypack, the user mixes the stereo input signal with the ambience to taste via an internal rotary knob. The bodypack also has a mode switch, allowing the user to flip between this Performance mix (used while playing) and a Full Ambient mode, typically used between songs. In the latter mode, the ambient audio is presented at full volume (unity gain) and the mix input is ducked, thus enabling normal conversation. In the PSS-3D configuration, these functions can also be served manually via the pre-DSP mixer.
According to Larry Revit, the 3D AARO is critical to the system, as it provides inherent access to both the ambient microphone and console mix signals, something no other IEM can deliver. This enables the specific processing needed to compensate for damaged hearing. Revit also notes, “The importance of the earpiece seal cannot be overemphasized, especially when severe hearing losses call for substantial high-frequency gain.” The deep fit and persistent seal of the medical-grade silicone earpieces is unmatched in this regard.
Hearing loss is a very personal experience, and can be devastating to any professional musician. This system combines multiple technologies that can bring the joy of live performance back into the lives of hearingimpaired artists, enabling effective monitoring without compromise.
Jack Kontney, President and Chief Caffeine Officer of Kontney Communications, handles marketing for Sensaphonics.