Passive Phone Amplifier – Nothing Phone 3a CompatibleA passive acoustic amplifier designed to enhance your smartphone's audio output without any power source or electronics — pure geometry doing the work.This model was designed around the Nothing Phone 3a form factor, with a base slot measuring 77.5 × 8.4 mm (3.05 × 0.33 in), making it compatible with any phone of equal or smaller dimensions. The internal channel is positioned to align with a bottom-right speaker placement, which is the standard configuration on the Nothing Phone 3a and many other phones. This deliberate asymmetry ensures the sound is captured and directed efficiently through the acoustic cavity, maximizing volume and clarity without any compromise.The amplifier works by funneling and projecting sound waves through a shaped resonance chamber — no cables, no charging, no Bluetooth. Just place your phone in and let the form amplify.A dedicated cable management notch is integrated into the design, allowing you to keep your phone docked in the amplifier while it charges — no need to remove it every time you plug in.Beyond function, the design was also conceived with aesthetics in mind: the iconic wave profile along the top edge gives the object a distinctive, sculptural character that looks just as good on a desk as it performs as an audio tool.

Key specs:

Base slot: 77.5 × 8.4 mm / 3.05 × 0.33 inDesigned for bottom-right speaker orientationCompatible with Nothing Phone 3a and smaller devicesFully passive — no power requiredIntegrated charging cable notchPrintable as a single piece.

Designed for BambuLab A1 but it's perfect for all printers.