Short answer: the Sennheiser CX Plus True Wireless, though neither ranks well in its class. It ranks #1138 of 1291 in-ear headphones by sound quality, rated 2.1/5, at $170.95. The Etymotic ER3SE ranks #1157, rated 2.0/5, at $149.99, $20.96 cheaper, a saving that is not big enough to make up the sound-quality gap. Both are rated below 3.0/5 among the 1291 in-ear headphones, and the Truthear Nova, ranked #2 at $169.99, is a better place to start if sound quality matters.
Why pick the Sennheiser CX Plus True Wireless: Supports aptX and aptX Adaptive along with AAC and SBC, so it streams well from Qualcomm based Android phones. The tradeoff: An 11.4 dB treble peak near 10.2 kHz makes cymbals and sibilance sharp and fatiguing, while a 6.6 dB shortfall from 3 to 6 kHz hollows out vocals.
What the Etymotic ER3SE does well: A single balanced armature at 22 ohms and 102 dB/mW reaches comfortable volume from any phone or laptop without an amp. The tradeoff: In oratory1990’s measurement sub-bass sits 9.9 dB below target and falls 6 dB short as high as 67 Hz, so bass lines sound thin and lack weight.
Buy the Sennheiser CX Plus True Wireless. It is rated higher for sound quality, and saving $20.96 with the Etymotic ER3SE does not make up for the sound-quality gap.
Looking for alternatives? See the complete Headphones rankings.
Supports aptX and aptX Adaptive along with AAC and SBC, so it streams well from Qualcomm based Android phones.
Amazon $170.95 eBay
A single balanced armature at 22 ohms and 102 dB/mW reaches comfortable volume from any phone or laptop without an amp.
Amazon $149.99 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
| Sennheiser CX Plus True Wireless | Etymotic ER3SE | |
|---|---|---|
| Price | $170.95 | $149.99 |
| Ranked | #1138 of 1291 in In-Ear Headphones | #1157 of 1291 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Harman Preference Score | 51 (median of 1 squig.link measurements, calibrated to AutoEQ) | 49 (measured by oratory1990, via AutoEQ) |
| Deviation From Target | 3.86 dB standard deviation | 4.18 dB standard deviation |
| Tonal Tilt | -0.76 (negative is warmer, positive brighter) | +0.73 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-2.6 dB at 30 Hz) | Falls 6 dB below target at 67 Hz (-9.9 dB at 30 Hz) |
| Connection | True wireless | Wired |
| Driver Type | Dynamic | Balanced armature |
| Drivers | 1 x 7mm dynamic | 1 x balanced armature |
| Weight | 0 lbs (6 g) per earbud | - |
| Frequency Response | 5Hz - 21kHz (Manufacturer specified) | 20Hz - 16kHz (Manufacturer specified) |
| Active Noise Cancelling | Yes | - |
| Battery Life | 8 hours (24 with case, Manufacturer specified) | - |
| Bluetooth Version | 5.2 | - |
| Bluetooth Codecs | SBC, AAC, aptX, aptX Adaptive | - |
| Built-in Microphone | Yes | No |
| IP Rating | IPX4 | - |
| Impedance | - | 22 ohms |
| Sensitivity | - | 102 dB/mW |
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