Fostex T40RP Mk3 EQ settings
Parametric EQ correction for the Fostex T40RP Mk3, derived from measurements by oratory1990. It moves the measured frequency response toward a neutral target.
How the T40RP Mk3 sounds before EQ
Measured against a neutral target, the T40RP Mk3 comes out warm. The low end sits ahead of the treble, which flatters bad recordings and rounds off detail.
The presence region, vocal clarity and attack, sits about 2.9 dB behind neutral, so detail and clarity soften. The bass region, punch and bass lines, sits about 2.9 dB forward of neutral, so bass lines carry extra weight. The mids region, vocals and most instruments, sits about 1.7 dB behind neutral, so vocals sit behind the instruments. The lower mids region, warmth and the body of voices, sits about 1.5 dB forward of neutral, so voices and guitars thicken up.
The deviations are moderate, topping out around 2.9 dB, which is clearly audible in a direct comparison. EQ makes a worthwhile difference.
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 58 Hz cuts the sub-bass by 8.3 dB with a broad band (Q 0.35).
- The filter at 105 Hz lifts the bass punch region by 7.6 dB with a shelf.
- The filter at 1.95 kHz lifts the vocal presence region by 4.7 dB with a medium-width band (Q 1.28).
The preamp of -4.7 dB offsets the boosts so nothing clips at full volume.
Parametric EQ settings
Preamp: -4.7 dB (prevents clipping from the boosts below)
| # | Type | Frequency | Gain | Q |
|---|---|---|---|---|
| 1 | Low shelf | 105 Hz | +7.6 dB | 0.70 |
| 2 | Peaking | 58 Hz | -8.3 dB | 0.35 |
| 3 | Peaking | 1.95 kHz | +4.7 dB | 1.28 |
| 4 | Peaking | 860 Hz | -2.4 dB | 1.50 |
| 5 | Peaking | 4.88 kHz | +2.7 dB | 1.37 |
| 6 | High shelf | 1 kHz | +0.2 dB | 0.70 |
| 7 | Peaking | 462 Hz | +1.4 dB | 3.24 |
| 8 | Peaking | 581 Hz | -1.2 dB | 4.70 |
| 9 | Peaking | 201 Hz | -0.5 dB | 3.41 |
| 10 | Peaking | 114 Hz | +0.3 dB | 3.13 |
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 T40RP Mk3 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.
T40RP Mk3 vs other Fostex 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 |
|---|---|---|---|
| T40RP Mk3 (this page) | warm | +1.1 dB | -1.9 dB |
| T50RP Mk4 | near-neutral | -1.6 dB | -1.5 dB |
| T-X0 | near-neutral | -1.8 dB | -1.9 dB |
| T20RP Mk3 | near-neutral | -1.0 dB | -1.0 dB |
| T50 | bass-light | -4.8 dB | -2.5 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 T40RP Mk3 is tuned and want alternatives.