But how does it sound? Overall, performance measurements for wireless speakers—or any small speakers—rarely get better than this.
Performance Measurements
The frequency response for the Play:1 on-axis, one meter in front of the tweeter, is shown in the blue trace of the above graph. The averaged response across a ±30 degree horizontal listening window is shown in the green trace. With a speaker frequency response measurement, you usually want the blue (on-axis) line to be as flat as possible and the green (averaged) response to be close to flat, perhaps with a mild reduction in treble response. This performance is one that the designer of a $3,000 per pair speaker could be proud of. On-axis, it measures ±2.7 decibels. Averaged across the listening window, it’s ±2.8 dB. This means that on-axis and off-axis performance are both superb and that the Play:1 should sound pretty good no matter where you place it in a room.
Design Considerations
There is a downward tilt from the low frequencies at left to the high frequencies at right. The Sonos engineers probably did this to keep the unit sounding full. It’s a well-known principle that rolling off the treble a bit in a product that doesn’t produce a lot of bass gives a more natural perceived tonal balance. The downward tilt is a result of using a 3.5-inch midrange woofer, which has broad dispersion because of its small size, placing the tweeter close to the mid-woofer to minimize interference between the two drivers, and applying generous amounts of equalization using the internal digital signal processor chip. It’s practically a case study in how a product like this should be designed.
All About the Bass
The -3 dB bass response of the Play:1 is 88 hertz, which is excellent for a speaker this small, and comparable to speakers with 4.5-inch woofers. Sonos seems to have put a lot of work into getting the little 3.5-inch woofer to play super deep, probably using a generous front-to-back motion range that lets it push more air and make more bass. The Play:1 has no problem with volume. It certainly plays loud enough to fill almost any home office or bedroom with sound.
