4 In – 2 Out – XLR Bypass Control A/B Switch Box – Ground Lift

Custom Passive XLR Audio Routing

4 XLR Inputs, 2 XLR Outputs, Balanced Signal Path, Input A/B Select Switch, and Pin 1 Ground Lift on Both Inputs for Noise-Free Audio Routing -System for RME, FiiO, Pro-Ject, Cayin & Rega

A fully passive, relay-free audio routing system designed for maximum signal integrity and flexibility. The unit allows seamless switching between multiple balanced audio sources and two independent signal paths: a direct full-balanced bypass path and an optional tube-buffer path.

Connected Equipment

• RME ADI-2 DAC FS
• FiiO DAC
• Pro-Ject Turntable (via balanced phono preamplifier)
• Cayin HA-6A MK2 (tube stage)
• Rega Osiris Integrated Amplifier

Signal Flow – see switch diagram – designed by customer – Zack Benjamin

• Selects between:
  • Tube Path: Signal processed through the Cayin HA-6A MK2.
  • Direct Bypass Path: Pure passive balanced connection with no active circuitry.
• Sends the selected signal to the Rega Osiris balanced XLR input.
• Ground Lift Switch – uDisconnects Pin 1 XLR Ground)

Design Features

• 100% passive audio routing
• No power supply required
• No relays or active electronics in the signal path
• Gold-plated switch contacts
• Full balanced XLR signal integrity maintained on the bypass path
• Excellent common-mode noise rejection throughout the balanced signal chain
• Minimal insertion loss
• Transparent signal routing with no coloration in bypass mode
• Instant A/B comparison between direct and tube-buffered playback

Intended Use

Designed for high-end audio systems where multiple balanced sources must be routed through either a pure direct path or a selectable tube stage while maintaining the shortest possible signal path and maximum audio fidelity.