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Fosi Audio i5 97mm Planar Magnetic Open Back Headphones vs Sennheiser HD 660S2 Wired Over-Ear Headphones

Every tracked fact about the two, side by side - prices, history lows, ratings and measured tuning. No verdict: which one to buy is the visitor's decision, always.

Fosi Audio i5 97mm Planar Magnetic Open Back Headphones Fosi Audio i5 97mm Planar Magnetic Open Back Headphones fosi Out of stock at every tracked store Lowest ever ₹47,691 on Friday, 25th Sept, 2026 Full prices & history
Sennheiser HD 660S2 Wired Over-Ear Headphones Sennheiser HD 660S2 Wired Over-Ear Headphones sennheiser Out of stock at every tracked store Lowest ever ₹29,800 on Thursday, 15th Oct, 2026 ★★★★★ 4.8 4.8 · 470 reviews Full prices & history

Measured tuning, side by side

Both curves are real community measurements (gold: Fosi Audio i5 97mm Planar Magnetic Open Back Headphones · ink: Sennheiser HD 660S2 Wired Over-Ear Headphones). Each is level-aligned to its own 200 Hz–1 kHz mean, so rig offsets don't skew the comparison.

201001k10k12-4-21
Fosi Audio i5 97mm Planar Magnetic Open Back Headphones Sennheiser HD 660S2 Wired Over-Ear Headphones
Tuning distance±3.16 dB RMS81% match - Close. Computed on a shared 40-point log grid, 20 Hz–10 kHz. A measurement-space fact, not a promise two ears agree.
What a curve cannot seeBuild, driver QC unit-to-unit, comfort, isolation, accessories, warranty and resale value sit outside the graph - usually what the pricier one is charging for.

The decision, factually

Cheaper right nown/aLowest current price across all tracked stores.
Deepest discount ever seenSennheiser HD 660S2 Wired Over-Ear HeadphonesFrom each product's own recorded price history.

This page reports facts and expresses no opinion on which to purchase.