Design Characteristics

The heart of the Purrfy

The heart of the Purrfy is its low, rumbling purr. Our research showed that a cat’s purr has many beneficial qualities. We knew it was essential for us to accurately replicate the sound and frequencies of those purrs. That goal brought some unique challenges.

The Purrfy is a small device, perfect for cupping in your hands or holding in your lap. Most small speakers, the kinds that would fit in a Purrfy, only reliably replicate sounds above 200Hz—but the sound frequencies of a cat’s purr range from 25Hz to 150Hz. If we used small speakers, the low rumbles of a cat’s purr would be missing.

This became one of our most important goals when designing the Purrfy, from the development of the concept through prototyping and production: we had to find a way to accurately reproduce those low frequencies. Without them, the Purrfy’s purrs wouldn’t be authentic. We conducted extensive tests on a wide variety of audio speakers. This led to many failures and discarded prototypes—until we finally found a model that matched our desired characteristics.

The Purrfy’s body

The Purrfy’s body is actually a sealed chamber with a powered speaker and a passive radiator. We linked the speaker to a low-frequency sound radiator in this air-tight chamber. The speaker’s movement creates internal air pressure changes and these changes move the passive radiator.

It’s this internal movement that generates much lower frequency responses and increases the Purrfy’s overall output. It gives us a deeper, tighter bass output and better efficiency at making high-quality sound. This arrangement adds to the efficacy of the low-frequency sound waves.

We also optimized the Purrfy’s audio circuitry for low-frequency ranges. This drives the haptic devices that create the mechanical vibrations—the feeling of the purrs. There are a variety of haptic exciters available, but we chose this specific model because of their efficiency in the low-frequency spectrum. We tried other, cheaper models, but they didn’t create the deep, rumbling feeling that we wanted.

It wasn’t easy finding a way to replicate accurate purrs in such a small device—but the Purrfy wouldn’t be Purrfy without them. Here, at the end of the long process of design, development, and testing, we’ve created a device that authentically replicates the soothing rumbles of a cat’s purr.