ARTICULATION TESTING METHODS 



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in sound proofing telephone booths, or in dealing with cross-talk. 

 The sentences have also been found to be useful in making quick 

 qualitative tests of the goodness of an audiphone set for a particular 

 case of deafness. 



Because of their general usefulness for these purposes, the complete 

 lists of sentences are given in the appendix. Due to memory effects 

 a set of sentences can be used with the same personnel only a very 

 few times. The psychological factors are also more prominent with 

 sentences than with simple syllable. 



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20 40 60 8C 



SYLLABLE ARTICULATION 



Fig. 12 — Articulation vs. time ratio 



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Sentence lists of the above type have also been used to obtain a 

 notion of how the time taken to transmit an idea correctly over a 

 system depends upon the articulation. To do this, the observer was 

 instructed to reply orally to the question. If the reply indicated 

 that the observer failed to understand, the speaker repeated the 

 question. Both speaker and observer tried to carry out the test in a 

 normal conversational manner. The observer could ask the speaker 

 to repeat, reword or spell out difficult parts of the sentence. 



The tests were made on a variety of systems of known syllable 

 articulation. The results that were obtained are shown in Fig. 12. 

 The ordinates of the curve give the ratio of the time required to 



