REAPER engineers on macOS and Windows want to hear their mix on their phone as it plays — no exporting, no bouncing. Here's how to route REAPER's master output to your phone in real time using Auxfeed, a free plugin you drop into the Master track FX chain.

What You Need

  • REAPER on macOS or Windows (any recent version)
  • Auxfeed plugin installed (auxfeed.com — AU/VST3/AAX on macOS, VST3/AAX on Windows)
  • Auxfeed app on your iPhone or Android phone, on the same Wi-Fi

Steps

1. Download and Install the Plugin

Go to auxfeed.com and download the Auxfeed installer for your platform. Run it, then relaunch REAPER. On macOS you can install AU or VST3. On Windows, install VST3. REAPER scans for new plugins at launch, or you can trigger a rescan via Options > Preferences > Plug-ins > VST and clicking Re-scan.

2. Open Master Track FX and Insert Auxfeed

If the Master track isn't visible, show it via View > Master Track. Click the FX button on the Master track — it's in the Master track control panel on the left side of the timeline. The Master FX chain window opens. Click Add, search for "Auxfeed," and double-click it to insert. The plugin window opens immediately.

3. Configure the Plugin

In the Auxfeed window, choose your codec: PCM Lossless for maximum quality, Opus for compressed audio that still sounds great. On iPhone, AAC is also available. Leave the PIN blank for open access on your Wi-Fi.

4. Open the Auxfeed App

Open the Auxfeed app on your phone. It auto-discovers the plugin via Bonjour — your REAPER session appears in the app within seconds. Tap to connect. No IP address or manual setup required.

5. Press Play in REAPER

Hit the spacebar or the transport play button. Audio begins streaming to your phone immediately. Walk away from the desk, listen through speakers or headphones, and use the LUFS meters in the Auxfeed app to check levels while you move.

REAPER Tip: Use a Send Track for Clean Parallel Monitoring

REAPER's routing flexibility gives you an alternative to the Master FX chain: create a new track, name it "Auxfeed Out," and send the Master to it at 0 dB. Drop Auxfeed on that track's FX chain instead. This lets you stream post-fader audio without inserting anything into your final output path — useful if you want to keep your Master chain clean for delivery or are experimenting with limiting you don't want to stream yet.

For a complete guide to using your phone as a reference monitor while mixing, see Phone as Studio Monitor — The Engineer’s Guide.

Start Hearing What Your Listeners Hear

Download the free Auxfeed plugin at auxfeed.com and the Auxfeed app on your phone. No account needed, free on both platforms — install and press play.