BKHC BK9 EQ settings
Parametric EQ correction for the BKHC BK9, derived from measurements by Innerfidelity. It moves the measured frequency response toward a neutral target.
How the BK9 sounds before EQ
Measured against a neutral target, the BK9 comes out bass-heavy. The low end dominates the tuning and can mask the mids.
The lower mids region, warmth and the body of voices, sits about 6.9 dB forward of neutral, so voices and guitars thicken up. The treble region, cymbals, sibilance and sparkle, sits about 6.2 dB behind neutral, so cymbals sound blunted. The air region, openness at the very top, sits about 6.0 dB behind neutral, so the very top closes in (measurements this high up vary between test rigs, so treat the exact number loosely). The presence region, vocal clarity and attack, sits about 4.3 dB behind neutral, so detail and clarity soften.
The largest single move in the correction is 7.8 dB around 675 Hz, on top of a broad tilt of up to 6.9 dB. That is not subtle. This model benefits clearly from correction.
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 bass-heavy 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
Summed across every filter, these are the changes the correction actually makes, largest first:
- Around 675 Hz the correction cuts the middle of the mids by 7.8 dB, over a broad band about 3.0 octaves wide.
- Around 12.6 kHz the correction lifts the air band by 6.9 dB, over a broad band about 2.5 octaves wide.
- Around 2 kHz the correction lifts the clarity region by 5.8 dB, over a medium-width band about 0.9 octaves wide.
The preamp of -6.8 dB offsets the boosts so nothing clips at full volume.
Parametric EQ settings
Preamp: -6.8 dB (headroom for the summed boost, not for any single row)
| # | Type | Frequency | Gain | Q |
|---|---|---|---|---|
| 1 | Low shelf | 105 Hz | -0.3 dB | 0.70 |
| 2 | Peaking | 696 Hz | -8.7 dB | 0.23 |
| 3 | Peaking | 5.86 kHz | +7.2 dB | 0.30 |
| 4 | Peaking | 1.9 kHz | +8.3 dB | 1.18 |
| 5 | Peaking | 3.09 kHz | -3.0 dB | 3.95 |
| 6 | High shelf | 10 kHz | +3.4 dB | 0.70 |
| 7 | Peaking | 70 Hz | -1.0 dB | 1.82 |
| 8 | Peaking | 9.28 kHz | -1.3 dB | 1.64 |
| 9 | Peaking | 341 Hz | +0.9 dB | 2.22 |
| 10 | Peaking | 689 Hz | -1.1 dB | 4.51 |
This is the published correction for the BK9, unaltered, in AutoEq format. It pastes straight into Equalizer APO or Peace on Windows, and into most parametric EQ apps. Enter every row, including the ones that cut. These are the values to use: the numbers are not rounded off or simplified for the page, because changing them would change the result.
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 BK9 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.
Headphones that sound similar
Closest matches across all 4,332 measured models, by distance between their deviation curves. Useful if you like how the BK9 is tuned and want alternatives.