ZonePlayer 120
Rebranded to Connect:Amp

2 x 55W audio power amplifier fed by SONOS signal management front end.

Status:

Discontinued

Role:

Product development resource
Test/Qualification infrastructure development

Description:

This was SONOS’ first powered zone player which had a production lifetime of over 10 years before being replaced by the ‘AMP’ product in 2018. The ZP120 power stage used a Sigma-Delta modulator based on Tripath’s Class-T design powered by an LLC power supply.

Innovations:

When I came on board the product was in advanced stage of development but had lingering concerns. SONOS at that time had no test infrastructure for power amplifiers and had little visibility of the product’s true performance over a wide range of critical parameters. I put in place a test and qualification infrastructure for audio products and created an Audio Precision test suite targeted to this class of products specific and unique requirements. This immediately revealed a fundamental design issue that produced massive amounts of distortion at low frequencies. The root cause was identified and corrected, resulting in a much cleaner measuring and sounding product.