CAST-1 Audio Casting

Apollo Automation CAST-1 Audio Casting Device The Apollo CAST-1 turns regular powered speakers, amplifiers, and AV receivers into Home Assistant / Music Assistant endpoints. Plug it into a 3.5mm line input, connect it over Wi-Fi, and stream music, announcements, alarms, and whole-home audio to the speakers you already own. It runs open-source ESPHome firmware and works locally — no cloud required. KEY FEATURES Makes existing speakers smart with Home Assistant and Music Assistant ESP32-S3 with ESPHome firmware TI PCM5122 32-bit stereo DAC 3.5mm analog line-out for powered speakers, amps, and receivers SendSpin support for synchronized multi-room audio Home Assistant announcements, alarms, and media playback Bluetooth proxy capable Onboard RGB status LED GPIO pads for an addressable RGB LED strip 100% local, open-source firmware SPECIFICATIONS Processor: MCU: ESP32-S3 Flash: 16 MB PSRAM: 8 MB Audio: DAC: Texas Instruments PCM5122 32-bit stereo 112 dB SNR / dynamic range Output: 3.5mm analog line out (2.1 VRMS full scale) Connectivity: Wi-Fi 2.4 GHz Bluetooth / BLE USB-C for power and programming Expansion: Solder pads for 5V, GND, and IO1 Onboard RGB LED Power: USB-C, 5V / 1A Physical: Size: 45 × 45 × 15 mm (1.8 × 1.8 × 0.6 in) Software: ESPHome (open source) Home Assistant Music Assistant via SendSpin Home Assistant Bluetooth Proxy Local control only — no cloud required What's Included: 1 × Apollo CAST-1 Audio Casting Device NOTES Connects to powered speakers, amplifiers, or AV receivers through a 3.5mm line input Ideal for adding Home Assistant audio, announcements, and multi-room music to existing speaker setups Firmware can be managed and customized through ESPHome