Sagittal sections

• Articulatory anatomy: Large interactive illustration of vocal tract anatomy with definitions
• The principal organs of articulation: Detailed set of images and definitions about speech articulators
• Interactive sagittal section: Specify articulatory parameters for consonants and see how they impact the vocal tract diagram

Vowel articulation

• Vowel articulation figures from Ladefoged (1982) [Internal, PDF]
• Comparison of features of two vowel articulation systems from Wood (1982) [Internal, PDF]
• Articulatory vowel features from Wood (1982) [Internal, PDF]

Movement and motor control

• Extensive recordings and models of vocal tract dynamics from KTH
• Phonetic Goals [Internal, PDF]

Imaging

• Different available techniques
• UCLA Phonetics Lab Physiology: Images of experiments involving EPG, EMA, airflow, and EGG
• X-ray images of speech articulation Subject saying Swedish "både" ("both"); follow links at top for more
• Speech Acoustics Laboratory: See 'Research' > 'Vocal tract imaging' on the top for MRI and CT images
• Articulatory animation: Animation illustrating how the motion of articulators during speech is quantified using EMA
• Vocal tract imaging links: Many downloadable videos of the vocal tract
• Specific consonant types
• MRI Images: Covers fricatives, laterals, and rhotics
• Vocal tract shape gallery excerpt: MRI images of vocal tract shape during various Swedish fricatives
• X-rays of the production of American English /r/ from Lindau (1980) [Internal, PDF]
• Pharyngeal phonetics: Laryngeoscopic animations of pharyngeal and epiglottal consonants [Requires QuickTime]

General information and resources

• A Sketch of the IPA Principles [Internal, PDF]
• IPA online: Includes a clickable chart, videos for tips on how to produce difficult contrasts, and practical exercises
• Phonetics: The sounds of spoken language: Interactive tutorial (with videos) covering English, Spanish, and German

Interactive (click-to-hear) IPA charts

• With audio only
• From IPAChart.com [Smartphone-friendly]
• From Voice & Speech Source [Uses Flash]
• From University of Victoria: [Requires QuickTime]
• From Jonathan Dowse [Click to download]
• With audio and video
• International Phonetic Alphabet: Click symbol for a video of the face when pronouncing that sound [Uses Flash[
• Seeing Speech: See "IPA Charts" on left for ultrasound videos for each IPA symbol [Uses Flash]
• rtMRI IPA chart: Click the symbol for an MRI video of that sound [Requires QuickTime]

Quizzing yourself

• From John Maidment (University College London): Various ways of quizzing yourself on IPA symbols
• From Ted Power: See 6 tests under "Self-correcting (interactive) tests" - Sounds and Spelling

Note: Both of the above resources are based on British English.

Tools for typing/displaying the IPA

• Information about IPA fonts
• IPA fonts and Unicode keyboard layouts can be downloaded from the Summer Institute of Linguistics (SIL).
• IPA 4 Linguists has detailed information, broken up into specific operating systems and software programs
• If you are still stuck, see also these guides by Bruce Hayes (University of California, Los Angeles), Jennifer Smith (University of North Carolina), and Jean-Philippe Goldman (University of Geneva).
• Online keyboards for typing IPA
• From Weston Ruter: Looks nearly identical to actual IPA chart
• From i2speak.com: Type letter and choose from similar-looking symbols
• From TypeIt.org: Only shows non-ASCII symbols, grouped by similarity to 26 English letters (in alphabetical order)
• From Richard Ishida: Toggle between multiple layouts; Many advanced features
• Codes for IPA symbols
• From Pennsylvania State University: Organized by similarity to English letters
• From John Wells (University College London): Organized by type of symbol

Airstream mechanisms

• Robert Eklund’s Ingressive Phonation & Speech Page: Collection of information about ingressive-airstream speech

Clicks

• Click chart from Traill (1992) [Internal, PDF]
• Fun Movies: Includes ultrasound imaging of clicks

Larynx

• Extensive online resources
• EGG & Voice Quality: Includes audio of different kinds of phonation and information about laryngoscopy
• Laryngeal anatomy
• Anatomia: Includes interactive model of larynx
• Normal Larynx Video: Video showing the function of a normal larynx during phonation
• The GASTROLAB Endoscopy Archives: Endoscopic pictures of the larynx
• Phonation
• Sketch of glottal position – state mapping [Internal, PDF]

General introductions to prosody

• Notes on the problems of IPA-style transcription for suprasegmentals [Internal, PDF]
• A Prosodic Glossary [Internal, PDF]
• A short guide to English Intonation [Internal, PDF]

Listen to the same English words/phrases pronounced with varying intonation patterns

• Monosyllabic and polysyllabic words: Plays in browser, with spectrograms and F0 contours [Internal, Pop-up]

Learn more about the English intonation system

• Transcribing Prosodic Structure of Spoken Utterances with ToBI: Download materials to teach yourself, step by step
• Guidelines for ToBI labeling, Version 2: Official conventions, with images and audio
• Original English ToBI homepage: Links to various websites and documents for learning more about the system

Intonation systems of various other languages

• Romance
• Romance generally: Interactive Atlas of Romance Intonation
• Spanish: Sp_ToBI training materials
• Catalan: Cat_ToBI training materials
• Portuguese: Interactive Atlas of the Prosody of Portuguese
• Other Indo-European languages
• German: G_ToBI: Training materials for German intonation [in German]
• Dutch: Transcription of Dutch Intonation
• Greek: Greek Tones and Break Indices (GRToBI): A brief manual
• East Asian languages
• Japanese: Japanese ToBI Labelling Guidelines
• Korean: K-ToBI (Korean ToBI) Labelling Conventions
• Cantonese: Cantonese Tones and Break Indices
• Taiwanese: Taiwanese Tones and Break Indices
• Information on the ongoing development of systems for other languages can be found at the Official ToBI homepage.

General acoustics

• Broad introductions
• From Zona Land Education Physics Department: With interactive applets to illustrate concepts
• From the University of Salford's Acoustics Program: With links to YouTube videos
• From PhysicsClassroom.com: See "Waves" and "Sound Waves and Music"; With questions to quiz yourself
• From HyperPhysics: Structured as a concept map; Navigate by clicking on the ovals
• Acoustics and Vibration Animations: Extensive collection of acoustics animations
• Focused on a specific topic
• An illustration of sound waves [Internal, PDF]
• Auditory scales of frequency representation: Information on units (octave/mel/bark/ERB) and an online converter
• Illustration of harmonics with synthetic signals [Internal, Pop-up]

Speech acoustics

• General introductions
• Physclips - Waves and Sound: Human Sound: Video demonstration with downloadable movie files [Uses Flash]
• Voice Acoustics: Several tutorials, including on speech in helium vs. air
• Tube models
• Recordings of three different tubes [Internal, Pop-up]
• Vocal Vowels: Images and audio of an artificial vocal tract
• Make your own vowel resonators!: Instructions on making a tube with household materials
• Nomograms
• Quantal theory figure from Stevens (1972) [Internal, PDF]
• Nomograms of vowel articulation from Stevens & House (1955) [Internal, PDF]

Spectrograms

• Characteristics of consonants and vowels
• Series of fricatives varying in place of articulation [Internal, Pop-up]
• Illustration of flapping in American English [Internal, Pop-up]
• Audio vowel dimensions [Internal, Pop-up]
• Practice reading spectrograms
• Spectral Cues for the Broad Categories of Speech Sounds: Covers all English phonemes; Includes explanations
• Monthly Mystery Spectrogram Webzone: The how-to discusses the basics; See the archives for many examples

Pedagogical software

• Illustrating basic theory
• ESYSTEM: Browser application to generate various kinds of sources and pass them through various kinds of filters
• Formant Synthesis Demo: Downloadable program for interactively illustrating formant synthesis
• Real-time visualization software
• From University College London: Includes real-time waveforms/spectra/F0/spectrograms [Windows only]
• sndtools: Real-time audio digital signal processing and 3D visualization
• WildSpectra and WildSpectraLive: Creates real-time spectrograms [Mac only]
• Frequency Analyzer: Create real-time spectrograms [Windows only]
• Convert spectrograms and other images into sound
• JavOICe [Requires Java]
• Coagula [Windows only]
• AudioPaint [Windows only]

Hearing

• General overviews
• Journey into the World of Hearing - Students and Professionals: Pedagogical resources about how hearing works
• Common Misconceptions about Hearing: Debunks several widespread myths and presents basic facts
• Hearing and balance: Online tutorial about hearing
• Virtual Tour of the Ear: Portal site containing links to information about hearing
• Focused on the inner ear
• The Cochlea: In-depth discussion of how the cochlea works, with images
• Cochlear Fluids Research Laboratory: Includes picture-based tutorials about hearing organs, especially the cochlea

Speech perception

• Overviews on specific topics
• Auditory perception: Tutorial on auditory perception, including some material on speech [Requires Java]
• Audiovisual Speech Web-Lab: Illustrations of the McGurk effect and similar phenomena
• The role of F0 in vowel perception: Audio files illustrating how vowel identity is cued by more than just formants
• Demos of speech perception experiments
• Categorical Perception: Illustration of a categorical perception experiment [Requires Java]
• Vowel Quality (Parts 1-4): Demonstration how vowel perception is affected by surrounding vowels

Learning about speech synthesis

• History
• Wolfgang von Kempelen's speaking machine and its successors: Information on early attempts at speech synthesis
• Dennis Klatt's History of Speech Synthesis: Sound samples from various generations of early speech synthesis
• The Pattern Playback: Information about the Pattern Playback, with audio
• Vocoded/sinewave speech
• An Introduction to Noise-Vocoded Speech: Synthesizing speech by modulating noise in different frequencies
• SineWave Synthesis: Mini-course on synthesizing speech using just sine waves
• An Introduction to Sine-Wave Speech: Playable audio of original speech and sinewave counterpart
• Modern approaches
• Current Techniques Speech Technology : Survey of modern approaches to speech synthesis
• TubeTalker Description: Based on anatomically correct model, with YouTube videos
• Talking Heads: Synthesizing both speech and facial movements
• Incorporating prosody and emotion
• Cynthia Speech Engine: Information (with audio samples) about a speech synthesizer that focuses on prosody
• Demonstration: Morphing Emotional Speech: Interactively synthesize along 3 emotional dimensions [Requires Flash]
• Listen to synthesized speech for many languages
• From the MBROLA Project
• From the University of Stuttgart

Demos of speech synthesis

• Dozens of languages
• Vocalizer 6: Online text-to-speech demo from Nuance, with support for dozens of languages/voices
• Acapela Group Voices Demo: Text-to-speech for several dozen languages
• English plus major European languages
• YAKiToMe: Supports English/French/German/Spanish
• AhoTTS, A Text to Speech System, Demo: Supports English/Spanish/Basque; Can specify several parameters
• Ogmios: Text-to-speech for English/Spanish/Catalan
• English only
• Festvox on-line synthesis demo: Supports several dialects of English, both male and female
• Festival Text-to-Speech Online Demo: Synthesize based on 4 different text-to-speech paradigms [Requires QuickTime]
• PHONWEB: Type a word or sentence in SAMPA transcription and hear it synthesized

Demos of speech recognition

• Automated Speech Recognition Demo: Speak from microphone or upload a file
• webASR: Web-based speech recognizer that analyzes a recording you upload

Lexical resources for designing experiments

• WebCelex: Use "Create Lexicon" to find English/Dutch/German words meeting specified criteria
• Wuggy: Automatically generate nonce words in various languages
• Neighborhood database: Information about English words' phonological neighborhoods
• Minimal pairs / Homographs / Homophones : Comprehensive listings (based on British English) [Links at bottom of page]
• CMU Pronouncing Dictionary: Downloadable computer-readable pronunciation dictionary for English
• Grady Ward's Moby: The 'Pronunciator' contains IPA transcriptions for 175 thousand English words

Recording tips

• Recording tips: Tips for making good-quality recordings
• Equipment for Audio Recording of Speech: Survey of the various available kinds of recording equipment

Typological databases

• PHOIBLE Online: A repository of segmental phonological inventory data for over 1600 languages
• UCLA Phonological Segment Inventory Database: Searchable database of phonemes across the world's languages
• World Phonotactics Database: Searchable database of phonotactic restrictions
• Stress System Database: Information about primary stress patterns in the world's languages
• The World Atlas of Language Structures Online: A large database on many languages, including phonological properties
• Vowel diagrams: Schematic diagrams of the vowel systems of 132 languages

While most corpora are sold commercially (many by the Linguistic Data Consortium), speech datasets are increasingly being distributed online for free. The websites linked below contain speech data that can either be browsed/downloaded immediately or require only a free registration process.

Repositories with holdings for various languages

• Language Archive: Hosts numerous speech and sign language corpora, many donated from researchers around the world
• Corpora of the Research Centre on Multilingualism: Holdings cover many European languages
• BAS CLARIN Repository: Dozens of corpora, mostly for German but also a few for English and Italian
• Speech and Language Data Repository: Hosts numerous speech corpora and tools, with an emphasis on French
• Speech Resources Consortium: Most corpora can be obtained without fee; Emphasis on Japanese
• Reciprosody: A repository of prosodically annotated material
• LibriVox: Free public domain audiobooks read by volunteers from around the world
• UCLA Phonetics Lab Archive: Includes recordings of many lesser-studied languages
• Phonetics Handbook Downloads: Audio files to accompany the official IPA descriptions of several dozen languages

Speech datasets for English

Isolated words/syllables

• Consonant vowel tokens: A database of 1700+ CV monosyllables (18 consonants, 3 vowels, 4 talkers)
• North Texas vowel database: Large vowel dataset, reporting measurements and with downloadable soundfiles

American English

• Buckeye Speech Corpus: Contains high-quality recordings from 40 speakers conversing freely with an interviewer
• Santa Barbara Corpus of Spoken American English: Multi-genre naturalistic speech with timestamped transcriptions

British English

• Audio British National Corpus (BNC): Digitized recordings of spontaneous speech, with time-aligned transcriptions
• Human Communication Research Centre (HCRC) Map Task Corpus: Multimodal interactional data with rich annotations
• Intonational Variation in English: Covers nine dialects in the British Isles; Includes prosodic annotations
• The Voices Recordings: Interactive atlas with downloadable speech samples from dialects around the United Kingdom

World Englishes

• Accents of English from Around the World: 110 words pronounced by speakers from 110 regions; Includes transcriptions

Non-native speakers

• Speech Accent Archive: Browse samples of a paragraph read aloud by natives and non-natives, many with IPA transcriptions
• International Dialects of English Archive: Browse samples of mainly unscripted speech, with orthographic transcriptions

With electroglottograph (EGG) data:

• CMU_ARCTIC: Phonetically balanced sentences in American/Canadian/Scottish/Indian English, with transcriptions
• Evaluating pitch determination algorithms: Recordings widely used as a baseline for evaluating F0 extraction algorithms

Speech datasets for other specific languages

• Japanese: C-ORAL-JAPONÉS: 12+ hours of monologues, dialogues and conversations
• Turkish: Spoken Turkish Corpus: Radio recordings; Extensive demo version can be downloaded for free

The majority of the links on this page point to external websites included in the large list of many hundreds of links from Joaquim Llisterri (Autonomous University of Barcelona) or other collections of links contained therein.

The links on this page here were hand-selected to be maximally useful as a supplement a graduate-level course in linguistic phonetics where English is the medium of instruction. The links are grouped by the different areas in which they typically arise in such a context.

The overall goal is to be a well-organized portal to only the most important resources, not to comprehensively index the contents of each site. As such, there is generally only one link per domain (at the highest level of the website relevant for phonetics).

Also, due to the nature of YouTube and Wikipedia, nothing from those sites is linked here. However, a large body of excellent material can be found there (e.g. videos of the cardinal vowels and laryngeal anatomy on YouTube).

Mixed in with the external links are a handful of PDFs and webpages developed and hosted locally at Indiana University. PDFs in this category are marked as [Internal, PDF]. Likewise, webpages that pop up in a separate window are marked with [Internal, Pop-up].