Author(s): Jared Bernstein, Kelsey Taussig, Jack Godfrey
LDC Catalog No.: LDC94S21
ISBN: 1-58563-034-9
ISLRN: 593-364-872-062-5
Member Year(s): 1994
DCMI Type(s): Sound
Sample Type: 1-channel ulaw compressed
Sample Rate: 8000
Data Source(s): telephone speech
Application(s): speech recognition
Language(s): English
Language ID(s): eng
License(s): LDC User Agreement for Non-Members
Online Documentation: LDC94S21 Documents
Licensing Instructions: Subscription & Standard Members, and Non-Members
Citation: Bernstein, Jared, Kelsey Taussig, and Jack Godfrey. MACROPHONE LDC94S21. Web Download. Philadelphia: Linguistic Data Consortium, 1994.
Related Works: View


MACROPHONE consists of approximately 200,000 utterances by 5,000 speakers. It is designed to provide material sufficient and suitable for research, development and evaluation of automatic speech recognition technology for common telephone applications, such as shopping, transportation, database access and autodialing. In addition to application-oriented phrases and numerous digit strings, seven sentences are spoken by each talker to provide ensemble phoneme, diphone and triphone coverage of the language. The spoken material also refers to times, locations, monetary amounts, spellings and interactive operations.


The utterances were collected automatically over the telephone network by recording directly from a T1 connection in 8 kHz, 8-bit mu-law format. The participants, roughly equal numbers of males and females, were solicited by a marketing firm from all regions of the United States. They ranged in age from the teens to the seventies and represented a broad range of educations and incomes as well. Each recorded utterance is accompanied by an orthographic transcription which also notes any unusual acoustic events or anomalies. Macrophone is the American English contribution to an international database of telephone speech corpora called POLYPHONE. Similar data sets are expected for major languages of the world and at least some of these will be made available through LDC. Prospects are currently good for American Spanish (by early 1995), Dutch, Standard French, Standard German, Japanese, Mandarin Chinese, Swiss French and Danish versions of POLYPHONE, all with basically the same structure and methods of collection.

MACROPHONE was collected at SRI under LDC sponsorship. A paper describing it was presented at ICASSP-94: "Macrophone: An American English Telephone Speech Corpus for the POLYPHONE Project," by Jared Bernstein, Kelsey Taussig and Jack Godfrey.


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