Frequency Response
20Hz-20kHz +/-2dB
+/-1.8dB
Within spec
Deviation from Harman target curve across audible range.
/// MEASUREMENT-DRIVEN
Measurement-Driven Reviews. No Hype.
124Reviews
5,800+Subscribers
22Years engineering
Coverage targets:
- What Hi-Fi
- Stereophile
- Headfonia
- Audio Science Review
- Innerfidelity
- The Verge
Coverage targets - placement pending (sandbox phase).
/// MEASUREMENT BENCH
Six specs, every review
Reference example below: Sennheiser HD800S vs Harman target curve. Each card shows mini SVG of the data captured during measurement.
THD+N at 90dB SPL
%
0.04%
Within spec
Total harmonic distortion plus noise at reference SPL.
Impedance
ohm at 1kHz
300 ohm
High impedance
Nominal impedance, amp matching critical above 150 ohm.
Sensitivity
dB SPL / mW
102dB
Within spec
Output SPL per milliwatt input - drives ease.
Channel Matching
L/R delta-dB
0.3dB
Within spec
Left/right driver matching - imaging integrity.
Square Wave 300Hz
transient
Clean
Within spec
Driver transient response - no ringing artifacts.
/// DATA HEAT-MAP
8 reference headphones · 12 measurement specs
Color coded vs Harman target: within spec marginal out of spec.
| Headphone | Type | Imp. | Sens. | FR +/-dB | THD% | Channel | Sub-bass | Mids | Treble | Soundstage | Verdict |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Sennheiser HD800S | Open | 300 | 102dB | 1.8 | 0.04 | 0.3 | marginal | within-spec | within-spec | within-spec | Recommended |
| Focal Utopia 2022 | Open | 80 | 104dB | 1.5 | 0.02 | 0.2 | within-spec | within-spec | within-spec | within-spec | Recommended |
| HiFiMan Susvara | Planar | 60 | 83dB | 2.1 | 0.06 | 0.4 | within-spec | within-spec | marginal | within-spec | Recommended |
| Audeze LCD-X 2025 | Planar | 20 | 103dB | 2.3 | 0.08 | 0.5 | within-spec | within-spec | marginal | marginal | Recommended |
| Bowers Wilkins P9 | Closed | 22 | 111dB | 3.2 | 0.12 | 0.8 | within-spec | marginal | out-of-spec | out-of-spec | Skip |
| Beyerdynamic T1 3rd | Open | 32 | 102dB | 2.6 | 0.05 | 0.4 | marginal | within-spec | marginal | within-spec | Recommended |
| AKG K712 Pro | Open | 62 | 105dB | 3.0 | 0.10 | 0.6 | out-of-spec | within-spec | marginal | within-spec | Marginal |
| Sony MDR-Z1R | Closed | 64 | 100dB | 4.1 | 0.15 | 0.5 | within-spec | marginal | out-of-spec | marginal | Skip |
Reference: ITU-R BS.1116 + Harman target curve 2017 revision. Heat-map thresholds: within-spec < 2dB deviation, marginal 2-4dB, out-of-spec > 4dB.
/// DAC + AMP PAIRINGS
Voltage swing matters
Reference DAC + amp combinations matched to each flagship headphone. Calculated from impedance, sensitivity and target 110dB SPL.
Sennheiser HD800S
300 ohm
DAC
Topping E70 Velvet
Amp
Topping A90 Discrete
High output voltage required - 300 ohm needs 5Vrms for 110dB SPL.
Chain price: $1,200
Focal Utopia
80 ohm
DAC
Chord Qutest
Amp
Schiit Mjolnir 3
Beryllium driver responds to transients - low-impedance tube/SS hybrid recommended.
Chain price: $3,800
HiFiMan Susvara
60 ohm
DAC
Holo Audio May KTE
Amp
SPL Phonitor x
Notoriously power-hungry - speaker-amp-grade voltage 6Vrms required.
Chain price: $7,200
Audeze LCD-X 2025
20 ohm
DAC
RME ADI-2 DAC FS
Amp
Burson Soloist 3X
Low-impedance planar - current delivery matters more than voltage swing.
Chain price: $2,400
/// LATEST FROM THE LAB
Recent measurements
12 most recent reviews. Updated every Tuesday.
Sennheiser HD800S - Measurement Deep Dive 2026
Frequency response +/-1.8dB Harman, THD 0.04%, channel matching 0.3dB. Recommended for analytical listening.
Focal Utopia 2022 vs HiFiMan Susvara - Measurement Comparison
Two flagship open-back headphones tested head-to-head with DAC/amp pairing recommendations.
Best DAC/Amp for Sennheiser HD800S - Measurement-Driven Pairing
6 DAC and 8 amp combinations tested with HD800S. Voltage swing requirements quantified.
Audeze LCD-X 2021 vs 2025 - What Changed
2025 revision tightens treble peak by 1.4dB, channel matching improved 0.2dB.
Harman Target Curve Explained 2026
What is the Harman target, why it matters, and how to read frequency response graphs.
Open-Back vs Closed-Back - Acoustic Physics
Why open-back measures differently in sub-bass and soundstage. Use case selector included.
Beyerdynamic T1 3rd Gen - Measurement Review
32 ohm impedance change vs 600 ohm predecessor.
Topping A90 Discrete vs Burson Soloist 3X
Two reference amps measured for distortion, output voltage, channel balance.
AKG K712 Pro - Budget Reference 2026
Sub-bass roll-off 6dB at 30Hz - viable for mixing but not mastering.
Sony MDR-Z1R - Flagship Closed-Back
13dB treble notch at 10kHz - coloration intentional but problematic for reference work.
Chord Qutest vs RME ADI-2 DAC Comparison
R2R vs sigma-delta DAC architectures compared with consistent test signals.
Bowers Wilkins P9 Signature - Measurement Review
V-shaped tuning 4dB bass plus 3dB treble - fun-sounding but non-reference.
/// SECONDARY · SUBJECTIVE ONLY
Listening notes
Below: subjective impressions only. Reference for color, not for buying decision. My ears, my room, my source material - your perception may differ.
Imaging
HD800S projects soundstage 30% wider than HD650. Susvara closer to speaker presentation. Utopia tighter focal points.
Dynamics
Planars (LCD-X, Susvara) trail dynamic drivers on micro-transients despite measurement parity.
Tonal balance
HD800S - analytical, slight upper-mid presence. Utopia - neutral with sparkle. Susvara - rich, slightly warm.
Use case fit
HD800S best for mixing. Utopia best for genre versatility. Susvara best for late-night critical listening.
Reference test tracks: Steely Dan - Two Against Nature 2000 24/96, Patricia Barber - Cafe Blue 1994 24/96, Massive Attack - Mezzanine 2019 24/96 remaster, Beethoven String Quartet Op.131 Takacs Quartet 1995 24/96.
/// VERDICT
Sennheiser HD800S
Recommended for
- Mastering engineers and mix referencing
- Critical analytical listeners
- Classical and acoustic music
- Owners of high-output DAC/amp ($800+)
Skip if
- You need sub-bass slam (electronic, hip-hop)
- Your amp output is less than 2 Vrms
- You prefer warm or colored tonality
- You need closed-back isolation
Alternative at same price
- Focal Clear MG - $1,499 - warmer voicing
- HiFiMan Arya Stealth - $1,299 - planar tonality
- Audeze LCD-X 2025 - $1,299 - studio reference
/// RIG DISCLOSURE
Calibrated measurement chain
HEAD acoustics HMS II.3 (calibrated quarterly by HEAD Berlin lab) + REW v5.20 + Audio Precision APx555 + Stax SRM-T8000 reference + dedicated isolation. Each headphone measured 7 positions, average curve published. Raw .frd files downloadable on request.
Full rig specs ->