Beyerdynamic DT 990 Pro Black
Score: 70/100
Sennheiser HD 660S2
Score: 79/100Rankings
The Sennheiser HD 660S2 is an open-back, wired audiophile headphone delivering refined detail, deep bass extension, and a premium build. Its high impedance and lack of wireless or ANC limit use to desktop setups with a quality amp. Best suited for critical listeners and home-studio environments.
The Beyerdynamic DT 990 Pro 80 Ω is an open-back, over-ear studio monitor headphone delivering a spacious soundstage and high comfort for critical listening. Its main drawbacks are the need for a strong amplifier, non-detachable cable, and lack of isolation, making it best suited for studio environments where amp power and quiet surroundings are available.
| Attribute | | |
|---|---|---|
— | 38 mmbest | |
| ↓ lower better | 340 g | 300 gbest |
80 Ω | 300 Ωbest | |
96 dB SPL | 104 dB SPLbest |
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| Attribute | | |
|---|---|---|
Audio(2) | ||
Impedance (Ω) | 80 Ω | 300 Ω |
Sensitivity (dB SPL) | 96 dB SPL | 104 dB SPL |
Build & Design(2) | ||
Weight (g) | 340 g | 300 g |
Dimensions (H×W×D) (mm) | 231 x 119 x 221 mm mm | 177.8x177.8x76.2 mm |
Products in the top-left offer the best value (high score, low price).
Professional reviewers consistently praise the DT 990 Pro for its reduced diaphragm mass that yields an exceptional impulse response, a wide soundstage and precise imaging that are ideal for critical mixing and mastering, and a rugged, replaceable-part construction. They also note the bright, V-shaped tuning and the necessity of a high-gain amplifier, while the open-back design is flagged as a limitation for isolation.
Everyday users love the comfort, solid build, and expansive soundstage that make long gaming or listening sessions enjoyable, but they frequently lament the need for a dedicated amp, the non-detachable cable on older models, and the bright treble that can become fatiguing. The open-back leakage is also a recurring point of dissatisfaction in noisy environments.
“Exceptional comfort with plush velour ear pads and lightweight build (≈250 g) suitable for long listening sessions.”
“High 250 Ω impedance requires a powerful headphone amplifier; not easily driven by portable devices.”
Professional reviewers consider the HD 660S2 a significant technical upgrade over the original HD 660S, citing its refined voice coil, lower resonant frequency, and enhanced airflow as key contributors to superior bass extension, clarity, and overall resolution.
Everyday users praise the HD 660S2 for its detailed, balanced sound and comfortable velour pads, while noting the need for a solid amplifier and the open-back design's lack of isolation.
