Sources & Further Reading
A curated map of the credible headphone-design literature — the foundational texts, the Harman research, the standards, and the measurement databases — with an honest note on where to start.
Reliable information on headphone design is scattered, and it clusters at two ends: deep acoustic theory on one side, and a fast-moving world of measurement data on the other, with surprisingly little practical “how to actually build one” in between. That gap is much of why Makerphones exists. This page is the map we wish we’d had — the credible sources worth your time, sorted by what they’re actually for, with an honest note on where to start.
Where to start
Section titled “Where to start”If you’re new and don’t want to be dropped into graduate-level acoustics cold:
- Read Sean Olive’s free summary of the Harman headphone research first (in Acoustics Today, 2022 — see below). It’s free, about 6,000 words, and it’s the single best on-ramp to how modern headphone sound is understood.
- Look at real measurements on Crinacle’s or oratory1990’s databases until the frequency- response graphs stop looking like noise. Pair that with the manual’s own chapter on reading frequency response.
- Then, if you want the why underneath it, Floyd Toole’s book for the psychoacoustics and Beranek & Mellow for the hard theory.
The rest of this page is the full shelf.
Foundational theory — acoustics and transducers
Section titled “Foundational theory — acoustics and transducers”The bedrock. Rigorous, math-heavy, and not light reading — but this is where the physics actually lives.
- Beranek & Mellow, Acoustics: Sound Fields and Transducers (and the second edition, Acoustics: Sound Fields, Transducers and Vibration). Tim Mellow’s modern update of Leo Beranek’s classic 1954 Acoustics. Covers earphones and transducers through electro-mechano-acoustical circuits, with worked examples aimed at practical design. The reference for the underlying physics.
- Loudspeaker and Headphone Handbook, edited by John Borwick (3rd ed., 2001). Mostly a loudspeaker book, but the “Headphones” chapter (ch. 14, by C.A. Poldy) is an extended, genuinely comprehensive treatment of headphone acoustics — one of the most thorough single references on the subject in print.
The science of “good” — psychoacoustics and preference
Section titled “The science of “good” — psychoacoustics and preference”The modern revolution: rigorous listening research into what people actually prefer, which gave the field a shared target.
- Floyd Toole, Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers, Rooms and Headphones. The definitive text on the perception side of reproduction; recent editions fold in headphones. Essential for understanding why measurements matter and how they connect to what you hear.
- The Harman headphone research (Sean Olive, Todd Welti, and colleagues). A roughly
nine-year listener-preference study that produced the Harman Target Curve, reported across
19-plus AES papers. The most influential body of modern headphone science. Access points:
- Free starting point: Olive, “The Perception and Measurement of Headphone Sound Quality: What Do Listeners Prefer?” — Acoustics Today (2022), a free PDF distilling the research in plain language.
- Accessible writing: “Audio Musings by Sean Olive” (seanolive.blogspot.com).
- Key papers: the “A Statistical Model that Predicts Listeners’ Preference Ratings of… Headphones” series (in-ear, then around-ear and on-ear), AES conventions, 2017–2018.
Foundational papers, and where the literature lives
Section titled “Foundational papers, and where the literature lives”- Møller, Jensen, Hammershøi & Sörensen, “Design Criteria for Headphones,” Journal of the Audio Engineering Society, Vol. 43, pp. 218–232 (1995). An early, foundational paper on the problem of designing headphones to a defined acoustic goal.
- The AES E-Library (aes.org). The canonical archive of audio-engineering papers, including most serious headphone research. Paywalled, but it’s where the primary literature lives — and AES membership or a university library gets you in.
Standards
Section titled “Standards”How measurement gets defined, so different rigs can agree.
- IEC 60318 series — specifications for ear and head simulators (the “ear simulator,” and the widely-used occluded-ear/“711-type” coupler) that measurement rigs are built to.
- ISO 11904 — methods for determining sound immission from sources close to the ear (the diffuse-field and free-field references).
- Worth knowing: the older diffuse-field calibration that these standards recommend is now widely regarded as outdated, having been largely displaced by preference-based targets like the Harman curve.
Measurement data and the modern ecosystem
Section titled “Measurement data and the modern ecosystem”Where makers and enthusiasts actually live now — public databases and open tools built on the research above.
These are live sites, tools, and hardware — links, ownership, and methods change. Treat the specifics as current-ish and verify before relying on them.
- oratory1990 — measurements on the gold-standard GRAS 45BC rig, referenced to the Harman target; widely treated as the reference source for over-ear data.
- Crinacle (graph.hangout.audio) — one of the largest public databases of headphone and earphone measurements, especially strong on IEMs.
- squig.link / Squiglink — a family of frequency-response database and comparison tools.
- AutoEq (open source) — automatic headphone EQ generated from frequency-response data, aggregating measurements from oratory1990, Crinacle, and others; a good way to see how measurements, targets, and corrections connect.
- Others: Rtings, Reference Audio Analyzer, and SoundStage Solo (Brent Butterworth), among more. The underlying hardware is usually a GRAS rig (the 45-series, or the 43-series).
- A standing caveat: measurements shift with the rig, the seating, and the pad wear, and a headphone never sounds exactly like its graph. Read measurements as strong guidance, not gospel — which is why good measurement means averaging several seatings.
Communities
Section titled “Communities”Where the conversation happens and questions get answered.
- Head-Fi — the largest and longest-running headphone enthusiast community.
- Audio Science Review (ASR) — measurement- and data-focused discussion.
- r/headphones, the DIY-audio forums, and the Fostex T50RP modding community — where the practical build-and-mod conversation actually happens, scattered as it is.
- The Audio Engineering Society (AES) — the professional body, its conventions, and its E-Library; the front door to the formal literature.
This list leans toward theory and measurement because that’s what credible, lasting sources exist for. The practical bridge between them — actually designing and building a headphone — is what the rest of Makerphones is for. Found a source worth adding? There’s a feedback link on every page.