Short answer: a tie on sound quality. Both are rated 3.9/5 (#465 and #534 of 1291 in-ear headphones) at nearly the same price ($24.99 vs $25), so choose on features and fit.
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. The catch: 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.
What the JCALLY Space does well: A budget single dynamic in-ear with a 10mm driver, a preference score of 72 and treble right on the Harman target. The tradeoff: Sub-bass falls about 3.7 dB short at 30 Hz.
Buy the 7Hz x Crinacle Zero 2 or the JCALLY Space on features: they are rated the same for sound quality at close to the same price.
Still deciding? The full Headphones rankings cover every ranked option.
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.
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A budget single dynamic in-ear with a 10mm driver, a preference score of 72 and treble right on the Harman target.
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Specifications Side By Side
| 7Hz x Crinacle Zero 2 | JCALLY Space | |
|---|---|---|
| Price | $24.99 | $25 |
| Ranked | #465 of 1291 in In-Ear Headphones | #534 of 1291 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Harman Preference Score | 73 (measured by crinacle, via AutoEQ) | 72 (median of 3 squig.link measurements, calibrated to AutoEQ) |
| Deviation From Target | 1.99 dB standard deviation | 2.17 dB standard deviation |
| Tonal Tilt | -0.71 (negative is warmer, positive brighter) | +0.43 (negative is warmer, positive brighter) |
| Connection | Wired | Wired |
| Driver Type | Dynamic | Dynamic |
| Drivers | 1 x 10mm dynamic | 1 x 10mm dynamic |
| Impedance | 32 ohms | - |
| Sensitivity | 108 dB SPL/V | - |
| Frequency Response | 10Hz - 20kHz (Manufacturer specified) | - |
| Back | Closed | Closed |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (+1.3 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (-3.7 dB at 30 Hz) |
Frequency Response Compared
Both headphones’ measurements overlaid on the Harman target. Above the target sounds louder in that range, below it quieter. Each curve is the median of several independent measurements, shifted so its 500 Hz to 2 kHz average sits at 0 dB, so only the tuning is compared.
Measurement data: the 7Hz x Crinacle Zero 2 from achoreviews, aftersound, ankramutt, atechreviews, banzai1122, bassaudio, csi-zone, dentreviews, ekaudio, gadgetrytech, iemocean, jaytiss, mmagtech, obodio, pw, regancipher, sl0the, soundignity, suporsalad, tdl and vortexreviews; the JCALLY Space from fernandagunsan, kuping-sensi and soundignity, all via squig.link.
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