Sennheiser HD620S Review

The Sennheiser HD620S occupies an interesting space: it's a closed-back headphone that sits squarely within the revered HD 600 series family — a lineage defined by open-back, audiophile-grade sound. The promise is bold. Can Sennheiser deliver that warm, detailed 6XX-like signature in a sealed package? Based on real-world owner feedback, the answer is largely yes — with a few asterisks.

Sound: Familiar Family Warmth, With a Catch

If you're coming from a Sennheiser HD 6XX or HD 650, the HD620S will feel like meeting a relative — same house, different room. One long-term owner described pairing the HD620S with a tube amplifier as making them "anxious to come back and listen more," which is about as high a compliment as you can get in this hobby. That warm, smooth, rich Sennheiser house sound is very much present here.

Out of the box, though, a few users found the stock tuning a touch shrill and bass-light — notably similar in character to the HD 560S. One reviewer running the headphone with a Q5K and Listener's PEQ preset described the result as simply "amazing." The takeaway: the HD620S rewards EQ. If you're willing to spend 10 minutes dialing in a preset, the ceiling gets noticeably higher. If you're a pure stock listener, manage your expectations slightly — it's good, not immediately great.

Comfort: A Genuine Standout

This is where the HD620S genuinely surprises. Multiple users called it the most comfortable closed-back they've owned — high praise given the competitive field. The leather earpads are a legitimate concern going in; closed-back leather pads and heat tend to go hand in hand. But real-world reports suggest the effect is mild compared to something like a Sony XM3, where ears reportedly get cooked within minutes. Long listening sessions appear to be quite manageable.

Where It Sits in the Sennheiser Ecosystem

Sennheiser's own product positioning is worth noting here. The newer HDB 630 wireless headphone was explicitly described by Sennheiser as sharing the same 600-series DNA as the HD620S — which is a backhanded compliment confirming the HD620S's audiophile credibility. For wired, closed-back listening, the HD620S is essentially the reference point within the family.

If you're weighing it against the open-back 6XX or HD 650: those will still edge it out for pure soundstage and natural imaging. But the HD620S is the answer when you need isolation — office environments, shared spaces, late-night listening — and don't want to compromise entirely on sound quality.

Value and Where to Buy

New retail pricing puts the HD620S firmly in the premium-but-not-absurd category. Refurbished units from Sennheiser direct have been spotted as low as $220, which — if the unit is in good shape — represents exceptional value. At that price point, it's difficult to find a closed-back with this level of sonic refinement and comfort combined.

Who Should Buy This — and Who Shouldn't

The HD620S is built for the person who already knows and loves the Sennheiser sound, needs a closed-back for practical reasons, and values listening comfort over long sessions. It's a strong pick for:

• HD 6XX / HD 650 owners who need a closed-back companion
• Office or shared-space listeners who can't use open-backs
• EQ-friendly users willing to apply a PEQ preset for the best results
• Anyone grabbing a refurb unit at a discount — that's a serious deal

It's less suited for:

• Buyers expecting the open soundstage of the 6XX out of the box — that's physically not possible in a closed design
• Strict stock-tuning purists who find the default sound a bit lean
• Anyone who runs hot and is already suffering with leather pads — it's better than most, but it's still a sealed leather cup

Buyer Tip

If you do pick these up, spend a few minutes finding a PEQ preset — Listener's preset has been specifically praised by HD620S owners. The transformation from "pretty good" to "genuinely impressive" is real, and it costs you nothing but a few minutes of setup time.

Frequently Asked Questions

Q: How does the HD620S compare to the Sennheiser HD 6XX or HD 650?

A: The HD620S shares the warm Sennheiser house sound but is a closed-back design, meaning soundstage and natural imaging won't match the open-back 6XX. The 6XX still wins on pure audio realism, but the HD620S is the better choice when you need sound isolation.

Q: Does the HD620S need an amplifier?

A: It benefits noticeably from amplification — pairing with a quality amp or DAC/amp combo draws out the warmth and detail. That said, it's not as amp-hungry as some of its open-back siblings and can function reasonably well from stronger dongles or portable sources.

Q: Is the stock tuning good, or does it require EQ?

A: Stock tuning is described as decent but slightly shrill and bass-light by some users. Applying a PEQ preset (Listener's preset is specifically recommended by owners) transforms the experience significantly. EQ-friendly buyers will get the most out of this headphone.

Q: Are the earpads comfortable for long sessions? Do they overheat?

A: Comfort is actually one of the HD620S's strongest points — multiple owners called it the most comfortable closed-back they've used. Heat buildup is milder than many competing closed-backs, though it's still a sealed leather pad, so extended summer sessions may eventually warm up.

Q: Is the refurbished HD620S from Sennheiser direct worth it?

A: At $220 refurb pricing, it's a strong value buy. Sennheiser's certified refurb units are generally reliable, and at that price you're getting a headphone that punches well above its cost.

— Tech Lead Editor, CPrice