Sennheiser HD 620S Headphones

Sennheiser HD 620S Headphones

What It Does in Your System

The First Closed-Back in Sennheiser's 600 Series

The HD 600 arrived in 1997 and has been a reference point ever since. Every headphone in that family has been open-backed, which means wonderful spaciousness and no privacy at all.

The HD 620S is the first closed-back member. It exists for the listener who loves how a 600 series headphone sounds but shares a room with someone who does not want to hear it.

Angled 42mm Drivers That Fight the Boxy Sound

Closed headphones usually sound narrow. Sealing the back traps sound behind the driver, and those reflections come back as congestion.

Sennheiser angles the 42mm transducers rather than pointing them straight at your ear, which is closer to how a loudspeaker reaches you across a room. Combined with a carefully developed baffle and damping, the goal is a wide stereo image without the closed-in quality.

A 150-Ohm Aluminum Voice Coil

The voice coil is aluminum and very light. Less mass means it starts and stops faster, which shows up as cleaner leading edges on notes and better-defined decay.

At 150 ohms the impedance is half that of the HD 600, so these are considerably easier to drive. The bass surround is adopted from the HD 660S2, which is why the low end goes deeper than 600 series listeners might expect.

Is This Right for You?

Three honest points:

• You need privacy without losing the 600 series sound. That is exactly what this headphone is for — a shared house, a quiet office, a room where an open-back pair is not welcome.
• The clamping pressure is firm. Several reviewers have found it tighter than they would like at first. It relaxes with use, but if you are sensitive to clamp, it is worth knowing before you order.
• At 150 ohms, a good source helps. These run from a phone or laptop, but they are not designed for it. A headphone amplifier or a decent DAC gets more out of them.

Setup & Installation

The cable is detachable and 1.8 meters long, ending in a 3.5mm plug with a locking screw thread. Screw the supplied 6.3mm adapter on for a home amplifier, or leave it off for a portable source.

A storage pouch is included, with room for the cable. Sennheiser also offers an optional balanced cable separately if your amplifier has a balanced headphone output.

Features & Specifications

42mm Angled Transducers
Custom-tuned drivers angled to widen the stereo image and reduce the boxy character of closed-back designs.

150-Ohm Aluminum Voice Coil
Ultra-light for fast transient response, and easier to drive than the 300-ohm HD 600.

Steel-Reinforced Construction
Reinforced headband sliders and stainless steel ear cup covers for durability and isolation.

Detachable Locking Cable
1.8-meter cable with a 3.5mm plug and locking screw, plus a 6.3mm adapter.

Specifications

• Style: Over-ear, closed-back
• Transducer: 42mm dynamic, angled
• Diaphragm: 38mm
• Voice coil: Ultra-light aluminum
• Impedance: 150 ohms
• Cable: Detachable, 1.8m, single-sided entry
• Termination: 3.5mm stereo plug with locking screw thread
• Ear pads: Artificial leather with internal venting
• Construction: Steel-reinforced headband sliders and ear cup covers
• Included: 6.3mm adapter, storage pouch

Frequently Asked Questions

How do these compare to the HD 600?
They share a family character but solve different problems. The HD 600 is open-backed, 300 ohms, and leaks sound freely. The HD 620S is closed, 150 ohms, easier to drive, and keeps your music to yourself — with a wider stereo image than closed headphones usually manage.

Do I need a headphone amplifier?
Not strictly. At 150 ohms they will play from most sources. But they respond well to a proper amplifier, and if you already own one these will use it.

Can I use these for gaming or recording?
Yes to both. The closed design keeps sound from leaking into a microphone, and the wide imaging helps with positional audio. Note there is no built-in microphone.

Why Audio Advisor?

• 40+ Years of Expertise – Helping music lovers build better systems since 1981.
• 60-Day Money-Back Guarantee – Hear it in your own system with confidence.
• Real Product Experts – Friendly advice before and after your purchase.
• Free Shipping – On qualifying orders over $49.
• Flexible Financing – Convenient payment options available.