Showing papers on "Noise published in 1970"

The effects of noise on man.

Abstract: Book on noise effects on man covering audiometry, aural reflex, hearing damage risk, physiological responses, motor performance and speech communication

Regulation of Voice Communication by Sensory Dynamics

Abstract: People speak more loudly in a noisy room or when momentarily deafened and more softly in a quiet room or when sidetone is artificially increased. The effort to compensate for these changes in the signal‐to‐noise ratio, or to match directly changes in the intensity of a model, typically falls about halfway short (in decibel units). This is probably because a speaker considers that he has doubled his own vocal level in half as many decibels as it takes to double the loudness of the signal or the noise. More concisely, the Lombard‐reflex, sidetone‐penalty and cross‐modality matching functions have exponents of about one‐half because the exponent of the loudness scale is half that of the autophonic scale of voice level. This amounts to saying that the speaker matches changes in signal or in noise to keep the signal‐to‐noise ratio nearly constant, but he is misled by the disparity in the sensory operating characteristics of speaking and listening.

Noise diminishing switching circuit for magnetic recording-reproducing device

Abstract: A magnetic recording-reproducing device comprises at least one switchable recording-reproducing head and at least one erase head. In a high-frequency bias recording system, high-frequency bias is applied to the recording-reproducing head in addition to the signals to be recorded on the magnetic recording medium. Also in a high-frequency erasing system, high-frequency erasing current is applied to the erase head. In both cases, in switching the operation modes of each head from one to the other and vice versa, the annoying noise is recorded on the recording medium because of the high-frequency current applied to the respective heads. In order to eliminate the noise, prior to mode switching of the heads, the high-frequency current is interrupted and thereafter high-frequency current is supplied to the heads.

Narrow-Band Noise Audiometry for Hard-to-Test Patients

Abstract: This study investigated the applicability, validity and reliability of narrow bands of white noise as test stimuli for obtaining audiograms under earphones with hard-to-test patients. The noise ban...

Auditory test facility with multistage single sideband heterodyning

Abstract: A facility for testing auditory characteristics of any person, but particularly a sonarman, and including a hi-fi speakerequipped sound insulated chamber for the test candidate and a hifi speaker-equipped test post for an acoustician, a hi-fi audio amplifier for the speakers, an intercom linking the sound insulated chamber and the testing position, a source of tonal sound and of noise and including controls at the test post, a pitch changing circuit coupled to the audio amplifier and pitch deviation metering circuit including dependent pitch controls in the chamber and at the testing post coupled to pitch changing circuit plush a pitch deviation meter at the test post. A switch at the test pose enables the acoustician to coupled the source of tonal sound wither to the test chamber directly or indirectly via the pitch changing and pitch deviation metering circuit.

Auditory and audio-visual reception of words in noise by observers with normal and impaired hearing

Abstract: Auditory and audiovisual reception of words in noise by observers with normal and impaired hearing"

Relative loudness judgments of material presented dichotically

Abstract: Three groups of 12 Ss listened to white noise of 80, 90, or 115 dB presented to one ear, while they shadowed words presented at an intensity of 90 dB to the other ear. Subsequently, they were asked to judge whether the noise or the speech was louder or if they were of the same intensity. All 12 Ss fudged 90-dB shadowed speech to be louder than 80-dB noise, 11 out of 12 Ss judged 90-dB shadowed speech to be louder than 90-dB noise, and 8 out of 12 Ss judged 90-dB shadowed speech to be louder than 115-dB noise. The results are interpreted as providing some support for Treisman’s filter-amplitude theory of attentional selection.

Paced recognition of words masked in white noise.

Abstract: An experiment is reported in which listeners make recognition responses to words mixed with one of five levels of noise and presented at one of five rates of presentation. An interaction is demonstrated between the effects of noise level and rate of presentation, which cannot be attributed to differences in enunciation of the test material at different rates of presentation.

Noise measurements at audio and subaudio frequencies using statistical analysis

Abstract: A fast method of measuring the power spectral density of transistor noise from dc to 10 kHz is described. The method is based on digital analysis of sampled data, and is applicable to a wide variety of noise measurements.

Measurement of Noise

Abstract: Environmental noise is widely noted as a form of "pollution." Measurement of noise intensity as a function of frequency is essential to its understanding and control. This is a tutorial paper summarizing standard current techniques and precautions to be followed in measuring environmental noise.