2023 · power routing

Truck audio system

One amplifier, two zones. Cab speakers are the default. An 8-channel relay dumps the same four speaker legs to a weather-capped bed port and a removable roof-box for the ultimate tailgate experience.

Phase 3 enclosure sitting on the cab roof, facing the bed — designed to be removable.

Cab or bed, same amp

The schematic is the design. Head unit to amplifier in the cab; relay COM takes four speaker legs; NC stays in the doors; NO runs out to the bed.

Cab path: head unit → 5 RCA → amp → sub + FL/FR/RL/RR. Default (NC) stays in the cab.
Relay COM takes the four speaker legs; NO dumps them to a weather-capped bed port and an 8-wire run to the roof box.
Covered toggle on the carpeted amp bay; 8-gauge feed; 150 A fuse; custom 3D-printed relay cover and bed-port chassis.
Phase 2 spent a long time on the scope killing clipping before the bed path existed. The same relay idea showed up later on the kiln.

Relay board, amp, and covered toggle — Relay pack and covered toggle in the amp bay.

Amplifier with new relays — Amplifier with the added relay bank.

Enclosure during wiring — Roof box during wiring.

3D-printed bed audio port wiring — Bed audio port — weather-capped connector chassis.

Bed port being fitted — Fitting the printed bed port.

Relay module stack

Cover lid, the 4-channel board, then the printed base — the sandwich that sits over the amp-bay relays. The bed-port chassis is the other print from this build.

Cover lid — top layer.

4-channel relay module.

Cover base — bottom layer.

Bed audio port chassis.