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Sennheiser HD 660S2 Wired Over-Ear Headphones - Black by Sennheiser - Refurbished - Excellent condition

Sennheiser HD 660S2 Wired Over-Ear Headphones - Black

Brand: Sennheiser

Condition: Refurbished - Excellent
$53598
$72190
-26% Save $18592
Updated: 15 days ago

Description

OVERVIEW:
Dive deeper into legendary sound: Enjoy your music on a completely new level. An intimate, relaxed sound signature combines with outstanding precision and exceptional comfort - and now, extended sub bass - for a deeply moving experience.
Every high-end headphone has its own unique personality. What if you could only own one?: Ever felt goosebumps from sound so real, it was as if the source was in the room with you? The non-fatiguing HD 660S2 gives people who love music an intimate way to connect more deeply with their favorite songs and artists. Breathtaking resolution and precision take you closer than ever to instruments and vocalists. Yet the sound is natural and balanced, never harsh or brash. This warm, inviting signature combined with extended sub bass makes listening uniquely pleasant and rewarding. And with comfort this good, it practically begs you to keep going for endless sessions. That’s how HD 660S2 combines the best of many worlds to give you an intimate experience you won’t want to live without.
Double the sub bass heightens your listening experience: Traditionally, audiophiles don’t get too excited about sub bass. It can easily get sloppy or boomy and become a distraction. And that’s a shame - because there’s so much more to experience here than just the gut punch of a kick drum. Did you know the low B of a 5-string bass vibrates at 30.9 Hz? Or that the lowest note on a concert piano comes in at 27.5 Hz? And of course, extended sub bass makes bass-heavy genres sound fantastic, too. And that’s the magic trick here. In doubling the sound pressure at the very lowest frequencies, we’ve nevertheless retained extraordinary precision and balance throughout the sub bass, mid-bass, and beyond. Most impressive is how this affects the listening experience. Extension on the low end changes everything - by creating more space for the sound. Against a deeper backdrop, highs feel more brilliant, the soundstage deeper, emotions stronger.
Comfy slippers, your favorite jeans, the HD 660S2. Some things just feel awesome to wear: The velour earpads of the HD 660S2 can only be described as a tactile pleasure. With just the right amount of tension for proper acoustic positioning and supple padding, the headband won’t draw attention away from your music, either. As an open-back design, the HD 660S2 gives your ears an extremely comfortable climate, even for super-long sessions. The low total weight and ergonomic headband rule out any potential discomfort on top of your head as well. Combined with excellent build quality made in Ireland, you’ll quickly grow attached to a listening experience that’s as physically pleasing as the warm, non-fatiguing sound at its heart.
Some of the most neutral headphones in the world are a tough act to follow: The surround is now more compliant, too, dropping the resonant frequency to 70 Hz. Considerable effort also went into optimizing the airflow around the transducer. There’s more sensitivity over the entire frequency spectrum because the magnet´s air gap works more efficiently now. Taken together, these measures result in even greater precision, speed, and resolution - with double the sound pressure at the lowest frequencies.

Specifications

  • Model Name: Sennheiser HD 660S2 Wired Over-Ear Headphones
  • Transducer Principle: Dynamic, Open
  • Transducer Size: 38 mm
  • Frequency Response: 8 – 41,500 Hz
  • Impedance: 300 Ω
  • Sound Pressure Level (SPL): 104 dB (1 kHz, 1 Vrms)
  • Total Harmonic Distortion (THD): <0.04% (1 kHz, 100 dB)
  • Ear Coupling: Over-Ear
  • Weight: 260g
  • Adapter: 6.3 mm (1⁄4 inch) to 3.5 mm
  • Connector: 6.3 mm (1⁄4 inch) jack plug, 4.4 mm balanced plug
  • Cable Length: 1.8m
  • Magnetic Field: 2.5mT

Frequently Asked Questions

Why Should I buy a Certified Pre-owned Sennheiser HD 660S2 Wired Over-Ear Headphones?
Get the same great performance and features as new, for a fraction of the price. A certified pre-owned Sennheiser HD 660S2 Wired Over-Ear Headphones is a smarter, more sustainable way to upgrade without breaking the bank. At Reebelo, every product is professionally cleaned, quality-tested, and backed by our warranty and 30-day free returns, so you can shop risk-free and ensure your purchase is the perfect fit. It's better for your budget, better for the planet, and always risk-free.
What does Reebelo's warranty cover?
Every purchase from Reebelo includes a Vendor Warranty of up to 12 months covering functional defects, giving you peace of mind and protection against unexpected issues. For tech products, our warranty covers all functional defects under normal use, as long as there's no physical or water damage by the customer. All products with batteries come with at least 80% capacity for reliable daily use. Many products offer upgrade options to 90% or 100%. You're covered for 12 months against battery failure and overheating. Want extra protection? Add our ReebeloCare Extended Warranty, an enhanced coverage plan that includes accidental damage from drops, spills, and other mishaps not covered by the 12-Month Vendor Warranty, available on select products.
Is a certified pre-owned Sennheiser HD 660S2 Wired Over-Ear Headphones reliable?
Absolutely! Every Sennheiser HD 660S2 Wired Over-Ear Headphones from Reebelo undergoes up to 70 rigorous quality checks, including professional inspection, cleaning, and repair to ensure it meets the highest standards of functionality. We work with trusted, certified vendors to guarantee top performance and long-lasting reliability, so you can enjoy your product with complete confidence.
How much can I save by buying a certified pre-owned Sennheiser HD 660S2 Wired Over-Ear Headphones?
At Reebelo, you can save up to 70% off retail prices on a Sennheiser HD 660S2 Wired Over-Ear Headphones, all while enjoying the same top-tier quality and performance. We're proud to offer certified pre-owned products from the brands you love — affordable, reliable, and thoroughly tested. Want to boost your savings even more? Trade in your old product with Reebelo and make your next upgrade even more affordable.
How does buying certified pre-owned products benefit the environment?
Purchasing a certified pre-owned Sennheiser HD 660S2 Wired Over-Ear Headphones is one of the most effective ways to reduce waste and minimize your carbon footprint. By giving high-quality products a second life, you're helping prevent valuable materials from ending up in landfills, where they can take centuries to decompose and release harmful toxins into the environment. Reebelo is committed to supporting a more sustainable, circular economy, where products are reused, refurbished, and kept in circulation for longer. This not only conserves resources but also reduces the need to manufacture new items, cutting down on energy consumption, raw material extraction, and greenhouse gas emissions. Make a smarter, greener choice — every certified pre-owned product you buy helps create a more sustainable future for all.

Sold by

Reebelo

Verified Retailer

Leading certified refurbished marketplace

  • 12-month warranty included
  • 30-day money-back guarantee
  • Environmentally conscious refurbishment
  • Grade-certified by expert technicians

Product Details

SKU:
ru-sku-mhz4x1ayYfoodZC5SuJ99IR
Country:
US

Shopping Smarter

Common questions about buying open-box and refurbished.

Why buy refurbished or open-box?
Refurbished and open-box products offer the same performance as new at a fraction of the price. You're already saving $186 on this listing. They've been inspected, tested, and are ready to use — the only difference is the price tag. Buying refurbished also reduces electronic waste, extending product life cycles and keeping functional devices out of landfills.
What's the difference between open-box and refurbished?
Open-box products are customer returns that have been inspected and confirmed functional. They may show little to no use — often the item was returned simply because the buyer changed their mind. Refurbished products have been professionally repaired or restored by technicians, tested to meet or exceed manufacturer specifications, and sometimes come with a warranty. Both are a smart alternative to buying new.
Why use OpenBoxFox?
Finding refurbished deals is time-consuming — you'd have to check Amazon Warehouse, Reebelo, Dyson Outlet, and others separately for Sennheiser products. OpenBoxFox aggregates these listings in one place, so you can compare and find the best deal without the legwork. We update pricing daily so you always see current availability and real savings.
Is it safe to buy refurbished?
Yes. Products listed on OpenBoxFox come from established retailers like Amazon, Reebelo, and Dyson — not unknown third-party sellers. Each retailer has buyer protection policies, return windows, and in some cases warranties. You get the price advantage of used goods with the purchase security of a known retailer.

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