By aspect — in detail
Mids
Strong consensus · 7 srcThe headline strength, alongside timbre: consistently called natural, neutral and slightly forward, with vocals and acoustic instruments singled out for realism. The one caveat is the ~3 kHz presence region, which can push bright or bad recordings toward 'shouty'.
“The mid-range is a hare forward, so instruments and vocals really come through well.”
Stuart Charles, Home Studio Basics
“vocals were tonally correct with a very warm sound character making them non-fatiguing.”
Gene DellaSala, Audioholics
Measured
ASR (GRAS 45C) reports the HD 600 tracks its neutral reference through the mids; DIY-Audio-Heaven notes a mild 1–2 dB lift between 3–7 kHz that lands on the upper mids/lower treble.
The defining HD 600 debate. Sources split on the measured ~3–6 kHz presence lift plus a gently rolled top octave: most hear it as smooth, well-calibrated and non-fatiguing — the 'Sennheiser veil' declared a myth — while a real minority hears the presence region as bright, etchy or 'shouty' on bright recordings.
Measured
DIY-Audio-Heaven measures a 1–2 dB lift between 3–7 kHz that gives 'a very slight extra edge in presence' versus the HD 650, over a top octave that rolls off gently; ASR reads the HD 600 as essentially identical to the HD 650 within the vagaries of headphone measurement.
⚠ vs. listeners — The camps aren't disputing a fact — 'smooth/well-calibrated' and 'bright/etchy/shouty' are opposite valences on the same measured presence lift, and it shifts with pad wear, recording and ears.
Where it splits
Smooth, well-calibrated and non-fatiguing — the fabled 'veil' is a myth on the HD 600.58%
“I really think the "Sennheiser Veil" myth with these cans is mostly the result of being compared to the many overly-bright headphones in this category (Grado, Audio Technica, AKG).”
Tyll Hertsens, InnerFidelity (Stereophile)
A mild presence lift that reads as bright/etchy and can get 'shouty' on some recordings.42%
“Be aware that bad recordings can make the 600s sound a bit shouty and in your face.”
Stuart Charles, Home Studio Basics
The core identity: neutral, flat and uncolored — the reference tuning of the family, without the HD 650's warmth hump, so it reads a touch brighter. A minority hears a mild warmth, but 'neutral reference' is the near-universal verdict.
“I find the HD600 to be very close to neutral, with a coherence from the bass up to the treble.”
Headphonesty
“Some call it the most uncolored headphone, being that it's extremely flat.”
Stuart Charles, Home Studio Basics
Measured
DIY-Audio-Heaven: 'exceptionally flat from 30 Hz to (at least) 20 kHz ±3 dB,' with the 30–500 Hz warmth hump the HD 650 shows kept flat here — which is why it sounds relatively brighter.
Agreement on the fact — the sub-bass rolls off below ~40–80 Hz and mid-bass is kept clean and flat rather than warm — but a preference split on the result: tight, articulate and 'enough' to some, light and short on slam to others. A mid-bass-neutral headphone, not a bass one.
“There is a light, but still present midbass bump around 100 Hz followed by a progressive roll off below 80 Hz.”
Headphonesty
“It rolls off below 40Hz, but still doesn't sound anemic or bass light”
Stuart Charles, Home Studio Basics
Measured
DIY-Audio-Heaven: rolls off below ~40 Hz and 'basically only lacks bass extension'; the 30–500 Hz region is flat (no HD 650-style warmth hump), so mid-bass stays tight rather than bloomy.
Soundstage
Moderate · 6 srcA clear weak point and a rare point of broad agreement: consistently heard as intimate and narrow — focused in the head rather than the wide, airy stage open-backs are known for. A few hear it open up with strong amplification.
“you absolutely shouldn't purchase these for gaming as the Soundstage is rather poor.”
Stuart Charles, Home Studio Basics
“The 650 is more refined and I feel this shows in its superior staging ability vs the 600.”
java_flavored_tea (r/headphones)
Praised well beyond the modest stage: sharp separation and placement are a genuine strength, one of the traits that keeps it a studio reference.
“The instrument separation is nothing short of exemplary.”
Stuart Charles, Home Studio Basics
Revealing and reference-grade for the price — it lays the whole recording bare — though the gently rolled top octave costs a little air, and modern planars out-resolve it.
“You are now able to hear almost everything that went into the recording, good or bad.”
Stuart Charles, Home Studio Basics
“it's a very revealing recording that you can hear details in the instruments and background noises that simply wash away on less than stellar equipment.”
Gene DellaSala, Audioholics
Dynamics
Contested · 6 srcPolarizing, and mostly about amping and expectation: fed a real amp many hear real impact and life; from a modest source, or against euphonic rivals, it reads laid-back — the root of its long-running 'boring' reputation.
Measured
A 300 Ω headphone that scales with real voltage: Headphonesty notes it sounds 'a bit dull' from a smartphone and comes alive on OTL/tube amps — so much of the 'boring' impression tracks the amp.
⚠ vs. listeners — The split is more about drive and expectation than the driver: underpowered or judged against euphonic sets it reads flat; well-amped and taken as a reference it reads engaging.
Where it splits
Accurate, engaging and lively with a capable amp — a benchmark, not a bore.70%
“The presentation is very engaging and somehow frontal as well as open.”
Headphonesty
Laid-back and 'lifeless' — the root of the 'boring' label.30%
“I tried them for around a week but everything just sounded lifeless and as you said, boring.”
bigdoghogfrog (r/headphones)
Comfort
Strong consensus · 6 srcStrongly positive and near-universal: light (~260 g), plush velour pads, fine for hours. The common caveat is a higher-than-average initial clamp that eases over time, and a fit that can feel tight on larger heads.
“you should be able to handle very long listening sessions without discomfort—I sometimes forget I'm wearing them.”
SoundGuys
“it clamps rather hard at first, but does open up over time.”
Stuart Charles, Home Studio Basics
Measured
≈260 g (Headphonesty/DIY-Audio-Heaven); velour earpads; clamping force measured 'high' (DIY-Audio-Heaven).
Plasticky and not luxurious — thin, dentable grilles and a cheap-feeling stock cable — but robust in practice, superbly assembled, and, unusually, fully user-repairable with off-the-shelf parts.
“just about every single part is replaceable through Sennheiser or one of its many resellers.”
SoundGuys
“The metal grilles on the HD 600 are a tad thin and can dent rather easily, this doesn't seem to effect the sound quality however.”
Tyll Hertsens, InnerFidelity (Stereophile)
Isolation
Strong consensus · 4 srcOpen-back by design: essentially no passive isolation and it leaks freely both ways. Expected for the type, not a flaw — but it rules out noisy commutes and shared rooms.
“very little noise isolation from the outside world along with excessive sound leakage making them less than ideal for the cubical office environment.”
Gene DellaSala, Audioholics
Widely seen as strong, lasting value — a reference tuning that stays repairable for decades — but the case is softened by fluctuating prices and by the cheaper, near-identical Drop HD 6XX (and HD 560S) sitting right next to it.
“the HD 600 is simply one of the best buys in the world of audiophile headphones.”
Tyll Hertsens, InnerFidelity (Stereophile)
“you can get the 6XX at a much better overall value.”
Stuart Charles, Home Studio Basics
