Filter 3-P

Modern systems carry interference from switching power supplies, wireless radios, and network hardware that couples into analog signal cables and shows up as noise in the audio. The Filter 3-P addresses that interference directly in the signal path, passing the audio through a filter circuit that attenuates common-mode noise by more than 80dB at 10kHz.

Distortion measures under 0.001% at 1kHz, and frequency response covers 10Hz to 150kHz, so the filter stays out of the way of the audio signal itself. It's available with RCA or XLR connections to match the cabling already in a system.

A Ground Lift switch on the underside disconnects the signal ground ahead of the transformer, a second tool for chasing down hum that persists even after filtering. Installed inline on an interconnect, it works with any component in the signal chain rather than a specific Octave product.