Sennheiser is one of the few mainstream audio brands who still launches wired headphones, yet people are interested, because Sennheiser HD series is a formidable legacy. Since 1997 and till today, the HD600 is still being manufactured and sold. The consumer line, although now under the ownership of Sonova, is still creating new worthy products to compete in the cut-throat market. Retailing for S$499 in Singapore, the HD620S is the most affordable 600 series headphones. The 1.8-metre cable is removable with a twist-lock, and I’m glad the package includes a soft carrying pouch.
I have previously reviewed several Sennheiser headphones, from the cheapest reference model HD560S, the evergreen HD650, the new classic HD660S, to the iconic flagship HD800S, and even the opulent HE1. Before I dive into comparing this new headphones with the rest of the Senns, you need to be aware of one thing: the HD 620S is a closed-back headphones. And it is the first closed-back wired cans that they launch this decade. The last time Sennheiser launched a closed-back model in 2018, the HD 820, it was not very well-received.
The advantage of closed-back headphones is that the audio is isolated and does not leak. People around you cannot hear the audio from the headphones, and neither can you hear clearly what’s happening around you. You can also hear musical details a lot better. The disadvantage is that the sound can sound tight, cluttered, and sonically less natural compared to open-back.
The Sennheiser HD 620S uses similar design headband mould as the HD560S but is has more metal to make it more sturdy. To me, the headband fit is also similar, where the pressure is against the rear of the ears instead of the middle because of the way the headband is held. The use of artificial leather cushions instead of velour ensures better sonic seal at the expense of breathability and longevity. The headband pads with a centre dent allows the HD620S to be hanged on headphone stands.
The cable choice is somewhat a compromise. On one hand, the 1.8m length is generous for mobile users, but too short for home users. At least a carrying pouch is included, but being just made of synthetic fabric, it does not offer any protection against knocks during travel. Still, it is of good use as a home storage protection against dust.
The sound quality can be summarised with the above official frequency chart from the website. There is more pronounced bass response and the treble is clear while not overly harsh. The midrange, on the other hand, leads with abundant presence, but if the song has strong midrange, it tends to overshadow the treble. Similarly, if the track mix does not have bright instrumentation (e.g. heavy hi-hats or synths), then the music might lack some sparkle. The sound staging is not too spatial, vocals are positioned more forward-centre, so you get good detail and presence without distracted with sibilance and harshness. Because it is closed-back, the finer musical elements can still be picked up, and the treble energy, albeit less than other headphones, is aptly contained.
Overall, the headphones provide immersive comfortable listen with controlled treble yet offering generous musical discipline. Genres that demand intimate midrange and bass presence, like saxophone or bright vocals, will perform well, but I would still like to boost the upper treble to extract more air. Positioning of the earcups around the ears could also alter the frequency balance, something that HD 620S is more susceptible.
Being so used listening to the FIIO FT3, the HD 620S turns out to be generally weaker in the treble but compensates in the midrange and lows. Conversely, after listening to the HD 620S for a considerable time, the FT3 turns out to be too harsh in the treble and lacking in bass.
Verdict
I never believe in “bad-sounding” headphones. When the product engineers tune the headphones, they are doing for specific target audience. The Sennheiser HD 620S is yet again a compromise that claims to deliver open-back experience. I would prefer that they just promote the headphones as immersive intimate musical sound. There is nothing wrong with closed-back headphones as long as the audio quality is great.
I feel that the new HD 620S tuning is meant for popular music produced in recent years, giving the listeners more bass while controlling the treble. It may not deliver the sparkling highs that I am accustomed to, but it makes me appreciate the same music from another perspective, with emphasis on midrange but more engaging bass and finer treble.
Sennheiser Consumer is retailing the HD 620S at S$499 in Singapore. Visit their official product webpage for details.