Short answer: the DUNU SA6 EST. Both are rated 3.5/5 for sound quality (#810 and #819 of 1291 in-ear headphones), and the DUNU SA6 EST costs $619 against $699.95 for the Sennheiser IE 600, so with nothing between them on sound quality, price settles it.
Why pick the DUNU SA6 EST: A broadly balanced tuning with a preference score of 68 against the Harman target. Watch for: Treble about 6 dB below target from 3 to 10 kHz, which can sound dull or veiled next to brighter headphones.
What the Sennheiser IE 600 does well: Sub-bass extends to 20 Hz with a slight 1.7 dB lift, and bass, low mids and upper mids all sit within about 1.3 dB of target, so the core of most music sounds full and natural. The tradeoff: In oratory1990’s measurement a 7.6 dB dip near 5.9 kHz and a presence band 5.5 dB under target take bite out of vocals and guitars, while a 4.7 dB peak near 9.7 kHz can sound sharp.
Buy the DUNU SA6 EST. Both are rated the same for sound quality, and it costs $80.95 less than the Sennheiser IE 600.
Still deciding? The full Headphones rankings cover every ranked option.
A broadly balanced tuning with a preference score of 68 against the Harman target.
Amazon $619 eBay
Sub-bass extends to 20 Hz with a slight 1.7 dB lift, and bass, low mids and upper mids all sit within about 1.3 dB of target, so the core of most music sounds full and natural.
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Specifications Side By Side
| DUNU SA6 EST | Sennheiser IE 600 | |
|---|---|---|
| Price | $619 | $699.95 |
| Ranked | #810 of 1291 in In-Ear Headphones | #819 of 1291 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Harman Preference Score | 68 (median of 7 squig.link measurements, calibrated to AutoEQ) | 67 (measured by oratory1990, via AutoEQ) |
| Deviation From Target | 2.55 dB standard deviation | 2.46 dB standard deviation |
| Tonal Tilt | -0.41 (negative is warmer, positive brighter) | -0.80 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-2.5 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (+2.3 dB at 30 Hz) |
| Connection | Wired (3.5mm / 4.4mm modular) | Wired |
| Driver Type | Tribrid | Dynamic |
| Drivers | 6 Balanced Armature, 2 Electrostatic | 1 x 7mm dynamic |
| Impedance | - | 18 ohms |
| Sensitivity | - | 118 dB SPL/V |
| Frequency Response | - | 4Hz - 46.5kHz (Manufacturer specified) |
| Built-in Microphone | - | No |
| Weight | - | 0 lbs (6 g) per earbud |
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 DUNU SA6 EST from atechreviews, ducbloke, eliseaudio, kazi, precog, soundignity and superreview; the Sennheiser IE 600 from achoreviews, adri-n, aftersound, animagus, aquaphobic, atechreviews, audioamigo, boizoff, csi-zone, dentreviews, digaoreviews, dl, ekaudio, eliseaudio, fahryst, freeryder05, gadgetrytech, harutohiroki, hbb, hobbytalk, hu-fi, iemocean, iemworld, jaytiss, kazi, lestat, mmagtech, musicafe, nymz, precog, recode, seanwee, sl0the, soundignity, superreview, theaudiostore, therollo9, timmyv and treblewellxtended, all via squig.link.
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