Fir Audio M4 EQ settings
Parametric EQ correction for the Fir Audio M4, derived from measurements by crinacle. It moves the measured frequency response toward a neutral target.
How the Audio M4 sounds before EQ
Measured against a neutral target, the Audio M4 comes out warm. The low end sits ahead of the treble, which flatters bad recordings and rounds off detail.
The treble region, cymbals, sibilance and sparkle, sits about 1.3 dB behind neutral, so cymbals sound blunted.
Overall this is a mild case: no band strays more than 1.3 dB from the target, so EQ here is optional fine-tuning rather than a fix.
These figures are read from the correction itself: whatever the EQ lifts, the headphone lacked, and whatever it cuts, the headphone had too much of. The target is the community's neutral reference, and how far above 10 kHz you can trust any measurement varies by rig. More warm models.
The correction curve
The solid line is the full measured correction (all 10 filters). The dashed line is what Atrium applies: the same shape at 65 percent strength, capped at 6 dB per band, so the headphone keeps its own character instead of being forced flat.
What the EQ fixes
The biggest moves in this correction, and what they do:
- The filter at 855 Hz lifts the middle of the mids by 3.1 dB with a medium-width band (Q 2.47).
- The filter at 8.91 kHz lifts the treble by 2.9 dB with a medium-width band (Q 2.18).
- The filter at 200 Hz cuts the upper bass by 2.5 dB with a broad band (Q 0.65).
The preamp of -2.9 dB offsets the boosts so nothing clips at full volume.
Parametric EQ settings
Preamp: -2.9 dB (prevents clipping from the boosts below)
| # | Type | Frequency | Gain | Q |
|---|---|---|---|---|
| 1 | Low shelf | 105 Hz | +1.2 dB | 0.70 |
| 2 | Peaking | 200 Hz | -2.5 dB | 0.65 |
| 3 | Peaking | 855 Hz | +3.1 dB | 2.47 |
| 4 | Peaking | 8.91 kHz | +2.9 dB | 2.18 |
| 5 | Peaking | 3.39 kHz | +2.2 dB | 3.01 |
| 6 | High shelf | 1 kHz | -1.1 dB | 0.70 |
| 7 | Peaking | 1.65 kHz | -1.7 dB | 2.15 |
| 8 | Peaking | 1.1 kHz | +1.0 dB | 4.48 |
| 9 | Peaking | 2.65 kHz | +0.9 dB | 3.71 |
| 10 | Peaking | 605 Hz | +0.4 dB | 3.44 |
This is the full measured correction in AutoEq format. It pastes straight into Equalizer APO or Peace on Windows, and into most parametric EQ apps.
How to use these settings
Manually: enter the preamp and each filter into any parametric EQ. On Windows that is usually Equalizer APO with the Peace interface. On a Mac, eqMac or SoundSource. Set the type, frequency, gain and Q exactly as listed.
With Atrium: pick your Audio M4 in the app and it applies a tuned version of this correction: 65 percent strength with a 6 dB per-band cap, which fixes the rough spots without erasing what the headphone does well. Atrium also measures how you hear with a short listening test and layers your personal hearing profile on top. Two people with the same headphones do not hear the same sound. Headphone corrections are part of Signature Edition; the app itself is free.
Audio M4 vs other Fir models
Bass and treble are each model's average distance from the neutral target in that range. Positive means more than neutral, negative means less.
| Model | Signature | Bass vs neutral | Treble vs neutral |
|---|---|---|---|
| Audio M4 (this page) | warm | +0.1 dB | -1.3 dB |
| Audio e10 | warm | +1.1 dB | -1.3 dB |
| Audio e12 | bass-heavy | +2.7 dB | +0.6 dB |
| Audio Krypton 5 | bass-heavy | +2.9 dB | -3.4 dB |
| Audio M2 | warm | +0.5 dB | -0.8 dB |
Headphones that sound similar
Closest matches across all 4,332 measured models, by distance between their deviation curves. Useful if you like how the Audio M4 is tuned and want alternatives.