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Sennheiser HD 660 S2 Open-Back Audiophile Headphones

Name: Sennheiser HD 660 S2 Open-Back Audiophile Headphones
SKU: AUD-33334
Price: 577.96 USD
Availability: InStock

In stock — ships free worldwide

Wired, open-back, over-ear · 38 mm dynamic, built in Ireland · 300 ohms. Brand-new — pay with crypto.

$578~~Was $680~~Save $102

≈ 0.009267 BTC+50 more coins

Estimate at the current rate. The exact amount is fixed when you place your order.

Free insured delivery in 5–6 business days

Need it sooner? Express 3–4 business days (+$45). Duties & taxes included.

30-day returns 1-year warranty Secure crypto checkout

Overview

About the Sennheiser HD 660 S2 Open-Back Audiophile Headphones

Sennheiser HD 660 S2 Open-Back Audiophile Headphones is one of Sennheiser's most popular picks this year. Sennheiser's open-back reference headphone from the HD 600 family, retuned with extended sub-bass. Highlights include Wired, open-back, over-ear and 38 mm dynamic, built in Ireland.

At CryptoBitMart the Sennheiser HD 660 S2 Open-Back Audiophile Headphones ships brand-new and genuine, with a 1-year warranty and 30-day returns.

Why buy the Sennheiser HD 660 S2 Open-Back Audiophile Headphones with crypto

Buy the Sennheiser HD 660 S2 Open-Back Audiophile Headphones with Bitcoin, Monero, Ethereum, USDT or 20+ other coins: the payment settles directly between wallets — no card issuer, no credit check and no banking data shared. Free insured worldwide shipping, duties included.

What's in the box

Sennheiser HD 660 S2 Open-Back Audiophile Headphones
Charging cable
Ear tips / accessories
Carry case
Original manufacturer packaging
Quick-start guide & documentation
1-year warranty card

Specifications

Category: Audio & Home Entertainment
SKU: AUD-33334
Type: Wired, open-back, over-ear
Transducer: 38 mm dynamic, built in Ireland
Impedance: 300 ohms
Voice Coil: Ultra-light aluminium
Ear Pads: Velour
Warranty: Global 2-year
Condition: Brand new · factory sealed
Warranty: 1-year global warranty
Shipping: Free worldwide · fully tracked
Returns: 30-day money-back guarantee
Payment: Bitcoin, Ethereum & 50+ cryptocurrencies
Availability: In stock

Questions

Something else? Ask our team — we reply within a few hours.

Is the Sennheiser HD 660 S2 Open-Back Audiophile Headphones brand-new and genuine?

Yes. Every product is brand-new, factory-sealed and quality-checked before dispatch, with serial labels intact.

What warranty is included?

A 1-year warranty against manufacturing defects, in addition to your statutory rights. Defective, damaged or incorrect items are replaced or refunded at no cost, including return shipping.

Will I pay customs or import duties?

No. Orders ship Delivered Duty Paid: import duty, VAT/GST and customs clearance are included in the price you pay at checkout, so there's nothing to pay on delivery.

How long does delivery take?

Orders are processed within 24–72 hours of your payment confirming on-chain, then shipped fully tracked and insured with DHL, FedEx, UPS or EMS. Free delivery usually arrives in 5–6 business days; Express and overnight options are available at checkout.

How do returns and refunds work if I paid in crypto?

You have 30 days from delivery to return an item in its original condition. Refunds are calculated in the USD value of your order, so price swings don't affect you, and sent as crypto to a wallet you choose or as store credit.

Which coins can I pay with, and who pays network fees?

Bitcoin, Ethereum, USDT, USDC, Solana, Litecoin, Monero and 50+ more. The crypto amount is locked for a short payment window when you place your order. Network fees are set by the blockchain and paid from your wallet.