Short answer: the Letshuoer D02. It ranks #263 of 450 in-ear headphones by sound quality, rated 4.0/5, at $26.99; the 7Hz x Crinacle Zero 2 ranks #275, rated 3.9/5, at $24.99. With prices this close, go by the sound-quality ranking rather than the cost.
What the 7Hz x Crinacle Zero 2 does well: Crinacle’s measurement gives it a preference score of 73, and an average deviation of just 2 dB from the Harman target is unusually even for a budget single dynamic driver. Watch for: Hobbyist measurements show the presence region about 3 dB shy of target with a 4.7 dB dip near 5.9 kHz, which can make guitars and vocal consonants sound a little veiled.
Buy the Letshuoer D02. It is rated higher for sound quality, and the $2 saving on the 7Hz x Crinacle Zero 2 is not enough to make up the difference.
Still deciding? The full Headphones rankings cover every ranked option.
Specifications Side By Side
| Letshuoer D02 | 7Hz x Crinacle Zero 2 | |
|---|---|---|
| Price | $26.99 | $24.99 |
| Ranked | #263 of 450 in In-Ear Headphones | #275 of 450 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Harman Preference Score | 74 (median of 7 squig.link measurements, calibrated to AutoEQ) | 73 (measured by crinacle, via AutoEQ) |
| Deviation From Target | 2.01 dB standard deviation | 1.99 dB standard deviation |
| Tonal Tilt | +0.33 (negative is warmer, positive brighter) | -0.71 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-3.4 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (+1.1 dB at 30 Hz) |
| Connection | Wired | Wired |
| Driver Type | Dynamic | Dynamic |
| Drivers | 1 x 11mm dynamic | 1 x 10mm dynamic |
| Impedance | 26 ohms | 32 ohms |
| Sensitivity | 108 dB | 108 dB SPL/V |
| Frequency Response | 20Hz - 40kHz (Manufacturer specified) | 10Hz - 20kHz (Manufacturer specified) |
Related Headphone Comparisons
How Letshuoer D02 compares with other leading options:
- Tripowin Vivace vs Letshuoer D02
- KZ ZSN Pro X vs Letshuoer D02
- 7Hz x Crinacle Zero 2 vs CCA CSN
- 7Hz x Crinacle Zero 2 vs KZ ZSN Pro
- 7Hz x Crinacle Zero 2 vs DUNU Titan S
Prices on this page were last checked October 11, 2026 at 4:59 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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The Two Headphones In Full
Letshuoer D02: $26.99 Letshuoer eBay
Full Letshuoer D02 review and specifications →
| Released | Aug 2025 (1 year ago) |
|---|---|
| Back | Closed |
| Connection | Wired |
| Deviation From Target | 2.01 dB standard deviation |
| Driver Type | Dynamic |
| Drivers | 1 x 11mm dynamic |
| Form Factor | In-ear |
| Frequency Response | 20Hz - 40kHz (Manufacturer specified) |
| Harman Preference Score | 74 (median of 7 squig.link measurements, calibrated to AutoEQ) |
| Impedance | 26 ohms |
| Sensitivity | 108 dB |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-3.4 dB at 30 Hz) |
| Tonal Tilt | +0.33 (negative is warmer, positive brighter) |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
7Hz x Crinacle Zero 2: $24.99 Amazon AliExpress eBay
Older model: the 7Hz Salnotes Zero (ranked higher, rated 4.8/5). See every 7Hz Zero generation.
Pros: Crinacle’s measurement gives it a preference score of 73, and an average deviation of just 2 dB from the Harman target is unusually even for a budget single dynamic driver. Across four hobbyist measurements on squig.link, bass sits about 1.8 dB above target and sub-bass reaches flat to 20 Hz, so kick drums and synth lines have a gentle, full weight without swamping vocals. The mildly warm balance suits listeners who like a relaxed, bassy tilt over a bright one.
Cons: Hobbyist measurements show the presence region about 3 dB shy of target with a 4.7 dB dip near 5.9 kHz, which can make guitars and vocal consonants sound a little veiled. A 4.2 dB lift near 11.9 kHz adds some sparkle on top that can draw attention to cymbals. The KZ ZSN Pro X rates slightly higher at a similar price.
Full 7Hz x Crinacle Zero 2 review and specifications →
| Released | Nov 2023 (2 years ago) |
|---|---|
| Back | Closed |
| Connection | Wired |
| Deviation From Target | 1.99 dB standard deviation |
| Driver Type | Dynamic |
| Drivers | 1 x 10mm dynamic |
| Form Factor | In-ear |
| Frequency Response | 10Hz - 20kHz (Manufacturer specified) |
| Harman Preference Score | 73 (measured by crinacle, via AutoEQ) |
| Impedance | 32 ohms |
| Sensitivity | 108 dB SPL/V |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (+1.1 dB at 30 Hz) |
| Tonal Tilt | -0.71 (negative is warmer, positive brighter) |
EQ preset to match the Harman target
Set a preamp of -4.4 dB, then add these filters in any parametric equalizer (Wavelet, Equalizer APO, Peace, or a player with parametric EQ). Calculated by AutoEQ from its measured frequency response.
| Filter | Frequency | Gain | Q |
|---|---|---|---|
| Low shelf | 105 Hz | -1.1 dB | 0.70 |
| Peak | 6,290 Hz | +4.3 dB | 0.72 |
| Peak | 182 Hz | -2.3 dB | 1.03 |
| Peak | 1,916 Hz | -1.7 dB | 0.50 |
| Peak | 855 Hz | +1.8 dB | 1.59 |
| High shelf | 10,000 Hz | +0.9 dB | 0.70 |
| Peak | 67 Hz | +0.4 dB | 2.53 |
| Peak | 7,224 Hz | -1.2 dB | 5.84 |
| Peak | 5,811 Hz | +0.8 dB | 5.07 |
| Peak | 3,871 Hz | -0.3 dB | 2.41 |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons