The qdc SUPERIOR ranks #540 out of 1253 total In-Ear Headphones for sound quality. See all Headphones rankings for every top pick.
Brand: qdc
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#540 qdc SUPERIOR: $99 eBay
Pros: A broadly balanced tuning with a preference score of 72 against the Harman target.
Cons: Treble about 2 dB below target from 3 to 10 kHz, which can sound dull or veiled next to brighter headphones. An uneven response, 2.2 dB standard deviation from target.
Is the qdc SUPERIOR right for you?
Buy it if
- you are sensitive to bright or sharp treble (treble sits 2.4 dB below target).
- you want sub-bass rumble that reaches down to 20 Hz.
Skip it if
- you want the best value: the higher-rated EPZ G10 costs about $75 less.
| Back | Closed |
|---|---|
| Connection | Wired |
| Deviation From Target | 2.18 dB standard deviation |
| Driver Type | Dynamic |
| Drivers | 1 x 10mm dynamic |
| Form Factor | In-ear |
| Harman Preference Score | 72 (median of 3 squig.link measurements, calibrated to AutoEQ) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-1.2 dB at 30 Hz) |
| Tonal Tilt | -0.07 (negative is warmer, positive brighter) |
EQ Presets
Harman target
Set a preamp of -5.5 dB, then add these filters in any parametric equalizer (Wavelet, Equalizer APO, Peace, or a player with parametric EQ). Calculated by Speaker Ranking from the median of 3 squig.link measurements, in the filter layout AutoEQ uses. Predicted Harman match with this EQ: 82 out of 100, up from 72.
| Filter | Frequency | Gain | Q |
|---|---|---|---|
| Low shelf | 105 Hz | +1.6 dB | 0.70 |
| High shelf | 10,000 Hz | -1.1 dB | 0.70 |
| Peak | 130 Hz | -2.2 dB | 0.88 |
| Peak | 610 Hz | +2.2 dB | 2.65 |
| Peak | 1,827 Hz | -4.1 dB | 3.89 |
| Peak | 3,150 Hz | +4.1 dB | 4.47 |
| Peak | 5,345 Hz | +3.0 dB | 0.83 |
Neutral target
Set a preamp of -5.6 dB, then add these filters in any parametric equalizer (Wavelet, Equalizer APO, Peace, or a player with parametric EQ). Calculated by Speaker Ranking from the median of 3 squig.link measurements, in the filter layout AutoEQ uses. Predicted Neutral match with this EQ: 86 out of 100, up from 43.
| Filter | Frequency | Gain | Q |
|---|---|---|---|
| Low shelf | 105 Hz | -6.9 dB | 0.70 |
| High shelf | 10,000 Hz | -1.1 dB | 0.70 |
| Peak | 110 Hz | -2.4 dB | 0.88 |
| Peak | 590 Hz | +2.3 dB | 2.07 |
| Peak | 1,827 Hz | -4.1 dB | 3.89 |
| Peak | 3,150 Hz | +4.1 dB | 4.47 |
| Peak | 5,345 Hz | +3.1 dB | 0.83 |
Studio flat target
Set a preamp of -6.8 dB, then add these filters in any parametric equalizer (Wavelet, Equalizer APO, Peace, or a player with parametric EQ). Calculated by Speaker Ranking from the median of 3 squig.link measurements, in the filter layout AutoEQ uses. Predicted Studio flat match with this EQ: 91 out of 100, up from 26.
| Filter | Frequency | Gain | Q |
|---|---|---|---|
| Low shelf | 105 Hz | -9.5 dB | 0.70 |
| High shelf | 10,000 Hz | +2.0 dB | 0.70 |
| Peak | 146 Hz | -4.0 dB | 0.88 |
| Peak | 618 Hz | +2.1 dB | 2.41 |
| Peak | 1,796 Hz | -3.2 dB | 4.18 |
| Peak | 2,688 Hz | +2.4 dB | 5.69 |
| Peak | 3,148 Hz | +6.0 dB | 2.61 |
| Peak | 3,667 Hz | +1.4 dB | 6.00 |
| Peak | 4,684 Hz | -2.8 dB | 6.00 |
| Peak | 5,972 Hz | +3.9 dB | 6.00 |
Warm target
Set a preamp of -4.1 dB, then add these filters in any parametric equalizer (Wavelet, Equalizer APO, Peace, or a player with parametric EQ). Calculated by Speaker Ranking from the median of 3 squig.link measurements, in the filter layout AutoEQ uses. Predicted Warm match with this EQ: 85 out of 100, up from 72.
| Filter | Frequency | Gain | Q |
|---|---|---|---|
| Low shelf | 105 Hz | +1.9 dB | 0.70 |
| High shelf | 10,000 Hz | -4.1 dB | 0.70 |
| Peak | 613 Hz | +2.5 dB | 2.22 |
| Peak | 1,842 Hz | -4.4 dB | 4.09 |
| Peak | 3,207 Hz | +4.3 dB | 4.32 |
| Peak | 4,677 Hz | -2.9 dB | 6.00 |
| Peak | 5,996 Hz | +4.1 dB | 6.00 |
Bass target
Set a preamp of -5.5 dB, then add these filters in any parametric equalizer (Wavelet, Equalizer APO, Peace, or a player with parametric EQ). Calculated by Speaker Ranking from the median of 3 squig.link measurements, in the filter layout AutoEQ uses. Predicted Bass match with this EQ: 84 out of 100, up from 64.
| Filter | Frequency | Gain | Q |
|---|---|---|---|
| Low shelf | 105 Hz | +5.2 dB | 0.70 |
| High shelf | 10,000 Hz | -1.1 dB | 0.70 |
| Peak | 141 Hz | -2.1 dB | 0.98 |
| Peak | 609 Hz | +2.2 dB | 2.63 |
| Peak | 1,827 Hz | -4.2 dB | 3.89 |
| Peak | 3,150 Hz | +4.1 dB | 4.47 |
| Peak | 5,345 Hz | +3.0 dB | 0.83 |
Bright target
Set a preamp of -6.1 dB, then add these filters in any parametric equalizer (Wavelet, Equalizer APO, Peace, or a player with parametric EQ). Calculated by Speaker Ranking from the median of 3 squig.link measurements, in the filter layout AutoEQ uses. Predicted Bright match with this EQ: 84 out of 100, up from 33.
| Filter | Frequency | Gain | Q |
|---|---|---|---|
| Low shelf | 105 Hz | -7.0 dB | 0.70 |
| High shelf | 10,000 Hz | +0.7 dB | 0.70 |
| Peak | 113 Hz | -2.4 dB | 0.89 |
| Peak | 593 Hz | +2.2 dB | 2.05 |
| Peak | 1,848 Hz | -4.3 dB | 3.15 |
| Peak | 2,942 Hz | +2.5 dB | 6.00 |
| Peak | 3,807 Hz | +5.7 dB | 1.49 |
| Peak | 5,789 Hz | +4.3 dB | 6.00 |
V-shaped target
Set a preamp of -6.6 dB, then add these filters in any parametric equalizer (Wavelet, Equalizer APO, Peace, or a player with parametric EQ). Calculated by Speaker Ranking from the median of 3 squig.link measurements, in the filter layout AutoEQ uses. Predicted V-shaped match with this EQ: 81 out of 100, up from 63.
| Filter | Frequency | Gain | Q |
|---|---|---|---|
| Low shelf | 105 Hz | +5.5 dB | 0.70 |
| High shelf | 10,000 Hz | +1.3 dB | 0.70 |
| Peak | 530 Hz | +2.4 dB | 1.73 |
| Peak | 1,276 Hz | -1.0 dB | 3.03 |
| Peak | 1,821 Hz | -4.1 dB | 2.96 |
| Peak | 2,881 Hz | +2.0 dB | 6.00 |
| Peak | 3,573 Hz | +6.0 dB | 1.55 |
| Peak | 5,747 Hz | +5.0 dB | 6.00 |
- Reviews, Comparisons and Sound Samples
Frequency Response
How the qdc SUPERIOR measures across the audible range, against the Harman in-ear target that most listeners prefer in blind tests. Where the line sits above the target that range sounds louder (more bass, brighter treble), below it quieter. The curve is the median of 3 independent measurements, so one odd sample or rig cannot skew it, and both lines are shifted so their 500 Hz to 2 kHz average sits at 0 dB.
Measurement data: median of 3 measurements from the squig.link databases of awsmdanny, dchpgall and ekaudio. Thanks to each of them for publishing their work.