Tangent spectrum X5 BT Manual De Instrucciones página 9

CONNECT A DIGITAL AUDIO SOURCE
In order to get a better audio quality, please use the digital input of the
Spectrum X5-X6BT.
This digital input is only compatible with stereo signal (PCM).
CONNECT A POWERED SUBWOOFER
If you need more bass, you can connect a powered Subwoofer to your
Spectrum X5-X6BT by using an analog RCA cable.