Free EQ for REAPER: when ReaEQ is enough, and when to add a dynamic EQ

ReaEQ, ReaXcomp and the gap between them

ReaEQ gives you low and high shelves, band, low-pass and high-pass, notch, band-pass, all-pass and a parallel band-pass type, with bands you add and remove freely, a phase display, and log-scaled frequency automation that makes sweeps easy to draw. For static tone-shaping and surgical cuts, it's all you need.

Level-dependent jobs in stock REAPER mean ReaXcomp, the multiband compressor, or automating ReaEQ by hand. Both work. A dynamic EQ is the more direct tool: a narrow band, placed exactly on the problem, with its own threshold, so it moves only when the problem is actually sounding.

• Keep ReaEQ for: high-passing, broad tone, static notches.
• Use ReaXcomp for: broad multiband control of a bus.
• Add a dynamic EQ for: sibilance, a resonance on loud notes only, kick/bass overlap, harshness that comes and goes.

Which AURORA format to load in REAPER

REAPER lists each format as its own entry in the FX browser ("CLAP: …", "VST3: …"), so the same plug-in can appear two or three times. The sound is identical. Pick one format, CLAP or VST3, and use it in every project, so templates and FX chains always recall the same entry.

Install and scan

If you install while REAPER is open, or a plug-in doesn't appear in the FX browser, run a full re-scan from Preferences.

• Copy the files into place (see the table), or run Install Aurora.cmd on Windows or install.sh on Linux.
• Open Options → Preferences → Plug-ins → VST. Check that the VST plug-in paths include your VST3 folder (use Add if not) and click Re-scan. If an updated plug-in looks stale, use the clear-cache re-scan option.
• For CLAP, the CLAP page under Plug-ins in Preferences has its own path list and re-scan.
• Open a track's FX window, type "Aurora" in the FX browser's filter, and add the format you settled on.
• On Linux, REAPER also reads LV2 from ~/.lv2. More on Linux formats in free EQ plugins for Linux.

Recipe 1: unmask kick and bass with a channel 3/4 send

This is REAPER's own way of sidechaining: tracks can carry more than two channels, and a plug-in's sidechain listens to channels 3/4. ReaComp does it by setting its detector input to Auxiliary Inputs. For AURORA, the plug-in's pin connector decides which track channels feed its sidechain input.

• Put AURORA on the bass track.
• Create a send from the kick track's channels 1/2 to the bass track's channels 3/4, in the kick's routing window or in the routing matrix.
• If AURORA's detector stays silent, open the pin connector (the "2 in 2 out" button in the FX window) and check that channels 3/4 feed the sidechain inputs.
• In AURORA, add a bell where the kick's weight sits, make it dynamic, set the detector to sidechain, and lower the threshold until it dips on each kick by a few dB.
• Or let Smart Ops' Unmask suggest the move and preview it on the curve before you apply it. The idea is explained in how to fix frequency masking.

Recipe 2: de-resonate a drum bus, then check with Delta

Put AURORA on the drum bus, choose De-resonate in Smart Ops and play the busiest section for at least two seconds. The suggested bands appear dashed on the curve before they touch the sound. Apply, then judge with Delta, which plays only what AURORA removes. If you hear the body of the snare rather than its ring, raise those bands' thresholds or narrow them. Auto gain keeps bypass comparisons at equal loudness, so the quieter version doesn't lose for being quieter.

REAPER's FX window has its own wet/dry knob with a delta solo. AURORA's Delta is latency-aligned inside the plug-in, so either works for a quick check.

Recipe 3: linear phase on the master

AURORA's Linear phase mode reports its latency to the host, and REAPER compensates plug-in latency so the master stays in time with the rest of the project. While you're recording through the project, switch AURORA to Zero latency or Natural (analog-matched, also zero latency) to keep monitoring tight.

Coming from another DAW? The Ableton Live and Bitwig Studio pages cover the same plug-in in those hosts, including how their sidechain routing differs.