Short answer: the TRN CS4. It ranks #730 of 1291 in-ear headphones by sound quality, rated 3.6/5, at $20.99; the KZ EDX Lite ranks #830, rated 3.5/5, at $18.99. With prices this close, go by the sound-quality ranking rather than the cost.
The case for the TRN CS4: A very cheap single dynamic in-ear with a 69 Harman preference score and full sub-bass extension down to 20 Hz. The tradeoff: Its score rests on three measurements.
Why pick the KZ EDX Lite: A very cheap single dynamic driver earphone with a confident, fun tuning: sub-bass and bass both sit about 4 dB above target, so electronic and hip hop tracks hit with real rumble. The catch: An 8.7 dB peak near 8.1 kHz adds sizzle and can make cymbals and S sounds sharp on bright recordings.
Buy the TRN CS4. It is rated higher for sound quality, and saving $2 with the KZ EDX Lite does not make up for the sound-quality gap.
Want more options? Browse the full Headphones rankings.
A very cheap single dynamic in-ear with a 69 Harman preference score and full sub-bass extension down to 20 Hz.
Amazon $20.99 eBay
A very cheap single dynamic driver earphone with a confident, fun tuning: sub-bass and bass both sit about 4 dB above target, so electronic and hip hop tracks hit with real rumble.
Amazon $18.99 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
| TRN CS4 | KZ EDX Lite | |
|---|---|---|
| Price | $20.99 | $18.99 |
| Ranked | #730 of 1291 in In-Ear Headphones | #830 of 1291 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Connection | Wired | Wired |
| Driver Type | Dynamic | Dynamic |
| Drivers | 1 x 10mm dynamic | 1 x 10mm dynamic |
| Sensitivity | 106 dB/mW | 108 dB |
| Harman Preference Score | 69 (median of 3 squig.link measurements, calibrated to AutoEQ) | 67 (median of 9 squig.link measurements, calibrated to AutoEQ) |
| Deviation From Target | 2.25 dB standard deviation | 2.23 dB standard deviation |
| Tonal Tilt | -0.49 (negative is warmer, positive brighter) | -0.80 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (+0.9 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (+3.6 dB at 30 Hz) |
| Impedance | - | 23 ohms |
| Frequency Response | - | 20Hz - 40kHz (Manufacturer specified) |
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 TRN CS4 from ankramutt, fahryst and ianfann; the KZ EDX Lite from ankramutt, audioamigo, eplv, kuping-sensi, obodio, suporsalad, tdl, therollo9 and yoshiultra, all via squig.link.
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