Short answer: a tie on sound quality. Both are rated 3.4/5 (#859 and #854 of 1291 in-ear headphones) at nearly the same price ($49.90 vs $49.90), so choose on features and fit.
The case for the Astrotec GX100: A broadly balanced tuning with a preference score of 67 against the Harman target. The catch: Treble about 2 dB above target from 3 to 10 kHz, which can sound sharp or tiring at higher volume.
What the EarAcoustic STA Pro does well: A broadly balanced tuning with a preference score of 67 against the Harman target. Watch for: An uneven response, 2.4 dB standard deviation from target.
Buy the Astrotec GX100 or the EarAcoustic STA Pro 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.
A broadly balanced tuning with a preference score of 67 against the Harman target.
Astrotec $49.90 eBay
A broadly balanced tuning with a preference score of 67 against the Harman target.
Linsoul $49.90 eBayPrices on this page were last checked October 16, 2026 at 5:46 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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Specifications Side By Side
| Astrotec GX100 | EarAcoustic STA Pro | |
|---|---|---|
| Price | $49.90 | $49.90 |
| Ranked | #859 of 1291 in In-Ear Headphones | #854 of 1291 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Harman Preference Score | 67 (median of 4 squig.link measurements, calibrated to AutoEQ) | 67 (median of 3 squig.link measurements, calibrated to AutoEQ) |
| Deviation From Target | 2.39 dB standard deviation | 2.41 dB standard deviation |
| Tonal Tilt | +0.98 (negative is warmer, positive brighter) | -0.55 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-4.3 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (+0.3 dB at 30 Hz) |
| Connection | Wired | Wired |
| Driver Type | Hybrid | Dynamic |
| Drivers | 1 DD + 1 PZT (1 x 10mm LCP dynamic driver + 1 x 10.6mm piezoelectric ceramic driver) | 2 x dynamic drivers (1 x 10mm graphene + 1 x 6mm titanium-plated) |
| Impedance | 32 ohms | 18 ohms |
| Sensitivity | 108 dB | 113 dB |
| Frequency Response | 5Hz - 40kHz | 10Hz - 30kHz |
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 Astrotec GX100 from audioamigo, pw, soundcheck39 and tonedeafmonk; the EarAcoustic STA Pro from avishai, lumerion and pw, all via squig.link.
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