<story><title>World’s smallest, best acoustic amplifier emerges from 50-year-old hypothesis</title><url>https://www.sandia.gov/news/publications/labnews/articles/2021/06-18/acoustic.html</url></story><parent_chain><item><author>jlnthws</author><text>Their device is tiny. I don&amp;#x27;t understand how it works with low frequency &amp;#x2F; large wavelength sound wave. Do you?</text></item><item><author>mikewarot</author><text>Surface Acoustic Wave filters are used in RF signal processing. They work by converting an electrical signal to a sound wave on the surface of a piezoelectric material, then using mechanical resonance effects to filter the signal to a very narrow band before converting it back to an electrical signal.&lt;p&gt;In this setup, they have figured out how to amplify the sound waves without having to convert them back to electrical signals first. The first prototype got hot, so they could only run it in pulses... the second device worked continuously, and delivered about a modest amount of power.&lt;p&gt;Eventually this technology will work its way down into all of our communications gear, making it even smaller, and more efficient.</text></item></parent_chain><comment><author>Zenst</author><text>Your instinct is spot on - it does not, and just does high frequencies in the RF range using acoustic resonance to amplify instead of using electrical amplification.  &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Acoustic_resonance&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Acoustic_resonance&lt;/a&gt;&lt;p&gt;One big aspect of this is that is from what can tell, has lower noise and with that a pre-amp&amp;#x2F;amp that has less noise in the RF domain is epic, it will allow lower power to be used for transmit and also offer longer range at the same power used today.  But an amplification that has less noise than existing electrical only options has so many uses that for discovery - I&amp;#x27;d rank this up there with graphite.</text></comment>
<story><title>World’s smallest, best acoustic amplifier emerges from 50-year-old hypothesis</title><url>https://www.sandia.gov/news/publications/labnews/articles/2021/06-18/acoustic.html</url></story><parent_chain><item><author>jlnthws</author><text>Their device is tiny. I don&amp;#x27;t understand how it works with low frequency &amp;#x2F; large wavelength sound wave. Do you?</text></item><item><author>mikewarot</author><text>Surface Acoustic Wave filters are used in RF signal processing. They work by converting an electrical signal to a sound wave on the surface of a piezoelectric material, then using mechanical resonance effects to filter the signal to a very narrow band before converting it back to an electrical signal.&lt;p&gt;In this setup, they have figured out how to amplify the sound waves without having to convert them back to electrical signals first. The first prototype got hot, so they could only run it in pulses... the second device worked continuously, and delivered about a modest amount of power.&lt;p&gt;Eventually this technology will work its way down into all of our communications gear, making it even smaller, and more efficient.</text></item></parent_chain><comment><author>mikewarot</author><text>I should have clarified &amp;quot;acoustic&amp;quot; just means a vibration, like sound, but in this case 274 megahertz, about 14,000 times higher pitch than human hearing... twice FM radio transmissions.&lt;p&gt;It eventually should result in devices that work past WiFi frequencies.</text></comment>