<h1>Audio Filter Grey -- AudéoWorld PFE Shopping Cart</h1> <b>$14.95</b> -- <i>The grey audio filters provide stronger middle tones. Fine tune your Audéo PFE to your unique listening preferences.</i> <p> <img src="https://store.nexternal.com/audeoworld/images/filter-white-lrg.jpg" align="right" alt="Audio Filter Grey" name="Audio Filter Grey" border="0" hspace="10" /> The easy-to-replace, passive audio filters adapt the frequency response to your individual listening preferences and provide crystal clear, luscious sound.<br aria-level="0" aria-posinset="0" aria-setsize="0" /><br aria-level="0" aria-posinset="0" aria-setsize="0" />The purpose of this filter is to provide you with the best quality sound that matches what you would hear naturally when not wearing ear tips. Hearing differs significantly from one person to another, and unlike standard earphones, Aud&#233;o PFE allows you to select the filter that works best for you.<br aria-level="0" aria-posinset="0" aria-setsize="0" /><br aria-level="0" aria-posinset="0" aria-setsize="0" />The grey audio filters provide stronger middle tones.<br aria-level="0" aria-posinset="0" aria-setsize="0" /><br aria-level="0" aria-posinset="0" aria-setsize="0" />The audio filter box comes with eight audio filters of the specified color and one changing tool<br aria-level="0" aria-posinset="0" aria-setsize="0" /><br aria-level="0" aria-posinset="0" aria-setsize="0" /><b aria-level="0" aria-posinset="0" aria-setsize="0">Technical background</b><br aria-level="0" aria-posinset="0" aria-setsize="0" /><br aria-level="0" aria-posinset="0" aria-setsize="0" />When wearing Aud&#233;o PFE the ear canal is blocked and the function of the ear is changed: <br aria-level="0" aria-posinset="0" aria-setsize="0" /><br aria-level="0" aria-posinset="0" aria-setsize="0" />1. The amplification of the pinna disappears.<br aria-level="0" aria-posinset="0" aria-setsize="0" />2. The natural resonance of the ear canal disappears. <br aria-level="0" aria-posinset="0" aria-setsize="0" /><br aria-level="0" aria-posinset="0" aria-setsize="0" />That has to be compensated by the earphone, so the target curve is theoretically the open ear transfer function, which corresponds to a flat curve in the free field and diffuse field:<br aria-level="0" aria-posinset="0" aria-setsize="0" /><table aria-level="0" aria-posinset="0" aria-setsize="0" border="0" cellspacing="1" cellpadding="2" align="center"> <tbody aria-level="0" aria-posinset="0" aria-setsize="0"> <tr aria-level="0" aria-posinset="0" aria-setsize="0"> <td aria-level="0" aria-posinset="0" aria-setsize="0" align="center"><img aria-level="0" aria-posinset="0" aria-setsize="0" border="0" alt="Open ear simulator transfer function graph" align="left" src="https://www.nexternal.com/audeoworld/images/pfe-graph.png" width="649" height="340" /> <br aria-level="0" aria-posinset="0" aria-setsize="0" /></td> </tr> <tr aria-level="0" aria-posinset="0" aria-setsize="0"> <td aria-level="0" aria-posinset="0" aria-setsize="0">&nbsp;Figure 1: Open ear simulator transfer function</td> </tr> </tbody> </table><br aria-level="0" aria-posinset="0" aria-setsize="0" />The earphones must recreate these phenomena for the user to perceive a natural sound.&nbsp; Since each person has a different ear, the compensation curves should be different from one person to the other. Standard earphones do not take these factors into account, which makes Audeo PFE unique. <br aria-level="0" aria-posinset="0" aria-setsize="0" /><br aria-level="0" aria-posinset="0" aria-setsize="0" />Internal studies at Phonak have shown that most people are not comfortable with a sound from an earphone that reproduces exactly the curve of a standard open ear.&nbsp; The curves of Audeo PFE are a compromise between a frequency response that includes the full open ear gain compensation as well as one that has bass and treble predominance.&nbsp; This compromise has been shown to produce greater satisfaction among test users, and therefore Audeo PFE offers two filter types to accommodate the widest range of user preference.<br aria-level="0" aria-posinset="0" aria-setsize="0" /></p> <p> <ul style="padding-left: 15px"> </ul> </p> <p><b>Other products in the category <a href="http://store.audeoworld.com/Category3" title="Accessories">Accessories</a>:</b> <br clear="left"><br /><ul style="padding-left: 15px"><li> <a href="http://store.audeoworld.com/Product7" title="Audio Filter Black">Audio Filter Black</a> -- The black audio filters provide stronger bass and treble. Customize any Audéo PFE for the sound you prefer.</li></ul> <br clear="left"><br /><ul style="padding-left: 15px"><li> <a href="http://store.audeoworld.com/Product17" title="Audio Filter Green - Perfect Bass">Audio Filter Green - Perfect Bass</a> -- The green audio filters provide stronger bass while maintaining high quality midrange. They are compatible with all PFE models.</li></ul> <br clear="left"><br /><ul style="padding-left: 15px"><li> <a href="http://store.audeoworld.com/Product5" title="Comply&amp;trade; Foam Tips">Comply&trade; Foam Tips</a> -- The Comply&trade; foam ear tips are for all models and create a snug, comfortable fit that significantly filtering our most ambient noise.</li></ul> <br clear="left"><br /><ul style="padding-left: 15px"><li> <a href="http://store.audeoworld.com/Product6" title="Silicone Ear Guides">Silicone Ear Guides</a> -- The soft silicone ear guides help route the cables around the ear for optimum hold and noise reduction.</li></ul> <br clear="left"><br /><ul style="padding-left: 15px"><li> <a href="http://store.audeoworld.com/Product4" title="Silicone Ear Tips">Silicone Ear Tips</a> -- Find your size and fit with this set of small, medium and large tips -- great noise isolation and no more annoying slips.</li></ul> </p> <br clear="left" /><br /><p><a href="http://store.audeoworld.com" title="Aud&#233;oWorld PFE Products">Aud&#233;oWorld PFE Products</a></p> <br clear="left" /><br /><br /><br /><br /> <br /><a href="http://na.audeoworld.com">AudéoWorld PFE</a> <br />AudéoWorld PFE Online Store powered by Nexternal <a href="http://www.nexternal.com" title="ecommerce solutions">ecommerce solutions</a>