Analog Angle Blog

Noise Monitor: Simple Ideas Can Be Winners

We have all heard the cliché, “Necessity is the mother of invention” and there’s a lot of truth to that, of course. There’s also a well-known principle that simple ideas – at least in intention, if not execution – are also more likely to be winners. If they solve an easy-to-describe problem, that’s even better.

I saw this once again when I read about a product called NoiseAware from a company of the same name. This acoustic-noise monitor is designed to solve a specific problem: overly loud tenants who therefore cause neighbor’s noise complaints and even fines that the property owner must pay. It’s especially well suited to short-term rentals and the parties they sometimes become, often associated with AirBnB-type situations.

The impetus for this product was simple and based on the co-inventor’s personal bad experience: he was renting out an apartment, things got out of hand with the supposedly quiet weekend renter, and he was hit with multiple fines and eventually had to sell at a loss. Wouldn’t it be nice if there was some way to intelligently monitor the noise levels, and send the property owner an alert when things got too loud?

The back story of the path from identifying a problem to developing a solution, including the path from a one-off solution to broader marketing of the product, is discussed in an article in The Wall Street Journal “How to Tell if Tenants Are Getting Rowdy? One Landlord Found a Solution” (sorry, it may be behind a paywall, but there’s a summary at the NoiseAware site)

Click here for larger image 
The small NoiseAware unit (left) provides text alarms and messages (right), plus a dashboard for setup and monitoring. (Image source: NoiseAware LLC)

The small NoiseAware unit (left) provides text alarms and messages (right), plus a dashboard for setup and monitoring. (Image source: NoiseAware LLC)

It plugs directly into the AC outlet and provides basic analog sensing of real-time sound level, filtering, and proprietary training algorithms for learning about the ambient situation. The unit distinguishes between near-field and far-field sound sources, looks at cumulative sound levels, and assesses other factors to avoid false triggers while not missing genuine crossing of user-programmable thresholds.

In the real world, of course, the meaning of “too loud” is much more complex than a simple set of dB readings, as there’s a difference between a dog bark and dishes crashing to the floor, as well as one-time impulse noise versus an ongoing excess. From my analog perspective, that’s all nice, but it’s all software and app code. The real news is the merging of the sound pressure detector (microphone) with a microcontroller-based circuit which digitized the sound, implements the algorithms, connects via 2.4 GHz Wi-Fi to the property’s network, and includes an integral AC/DC supply (no AC/DC wall wart needed). The device – or multiple ones at the same apartment or house, for more thorough coverage – is supported by a web browser as well as a dashboard. Since it does not record or transit ongoing audio, there are no privacy concerns. The end result is simple enough: the properly owner/manager gets a text message or email where the NoiseAware detects excessive noise levels.

When you think about it, there’s nothing in this type of product that requires a technology breakthrough by the developers. It’s an “obvious” combination of existing components, and something that an individual or small team can design, build, and get into production. It’s a reminder that not all good ideas require huge investments, large teams, or complicated scenarios; they can, instead, be direct solutions to well-defined problems. Many of these designs start with sensors such as the audio here, although I am also seeing many others on Kickstarter and elsewhere that are leveraging MEMS-based accelerometers and gyros, temperature sensors, and pressure sensors. The combination of low-cost, fairly accurate, and easy-to-interface sensors (many include integral digitization and a serial interface) makes these projects practical with low or modest design effort.

Have you ever had a “I could have done that” or “I also thought of that” moment for a relatively simple device that solves a clear problem? So, what happened?

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1 comment on “Noise Monitor: Simple Ideas Can Be Winners

  1. ThomasMaloney
    August 9, 2018

    I think that it's a good thing that there are people around who are driven to find solutions for existing systems and framework. I think that a lot of people actually go by the saying that “if it ain't broke, then don't fix it. But of course, we see the innovations that stem from creating new solutions really changing the landscape of the industry more often than not and perhaps we should remember that sometimes we should force ourselves to improve..

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