Bell System Technical Journal, 3: 4. October 1924 pp 531-549. "The Stethophone," An Electrical Stethoscope. (Frederick, H.A.; Dodge, H.F.)
Topics: sounds, stethoscope, frequency, stethophone, heart, filter, electrical, transmitter, receivers,...
R&D Report 1965-09 : Goodmans 'Maxim' loudspeaker. H.D. Harwood Tests have been carried out on a wide-range loudspeaker of unusually small dimensions marketed by Goodmans Industries under the trade name 'Maxim'. The small size of this loudspeaker has been achieved at some sacrifice of efficiency and of power output capacity at low frequencies; however, given sufficient amplifier power and some degree of electrical equalisation, the performance, judged by the specimen tested, would be...
Topics: loudspeaker, frequency, goodmans, inches, sound, characteristics, frequencies, output,...
R&D Report 1967-57 : The design of studio monitoring loudspeakers Types LS5/5 and LS5/6 H.D. Harwood, S.A. Hughes Details are given of the various factors which have led to the design of two new monitoring loudspeakers suitable for use in studios and outside broadcasts. The loudspeakers are much smaller than those of the present type; a floor standing model is designated type LS5/5, and one intended for hanging is called type LS5/6. In the course of the design, the questions of bass...
Topics: frequency, unit, loudspeaker, slit, axial, type, bass, khz, loudspeakers, characteristics, axial...
R&D Report 1964-67 : Stereophony: the effect of differences between the amplitude / frequency characteristics of left and right channels D.E.L. Shorter, H.D. Harwood, W.I. Mason In a stereophonic transmission system, differences between the amplitude/frequency characteristics of the left- and right-hand channels may result in displacement or dispersion of the sound images across the stage. These effects have been subjectively assessed for such differences in channel characteristics as might...
Topics: frequency, image, characteristics, amplitude, width, differences, interchannel, channels,...
R&D Report 1966-19 : The Sennheiser Type MKH 805 microphone. H.D. Harwood This report describes tests carried out on a capacitor type end-fire line microphone made by the German firm of Sennheiser. The head amplifier has transistor circuits and radio frequency biassing of the capsule. Measurements have been made of the frequency characteristics on the axis and at a number of angles to it; the degree of interference from wind and from magnetic fields has also been determined. The quality of...
Topics: frequency, sennheiser, microphone, noise, directional, impedance, mkh, type, measurements,...
R&D Report 1969-05 : The design of the LS3/4 loudspeaker H.D. Harwood, S.A. Hughes A description is given of the design and performance of a compact two- unit loudspeaker for use in mobile control rooms. Both the frequency range and the quality of reproduction are similar to that of the studio monitoring loudspeaker type LS5/5 from which this design was developed; the power handling capacity, whilst less than that of the LS5/5, is quite adequate for the purpose.
Topics: loudspeaker, frequency, unit, sound, units, design, axial, khz, impedance, crossover, studio...
R&D Report 1954-41 : The AKG electrostatic microphone Type C12. H.D. Harwood, R.J Packer A new electrostatic microphone, type C 12, has been produced by the firm of Akustische und Kino-Gerate Gesellschaft in Vienna. The nominal polar characteristic of the microphone can be varied from omnidirectional through cardioid to a figure-of-eight by a multi-position remote control switch. Frequency response, sensitivity and noise have been measured on a single specimen for these three conditions....
Topics: frequency, microphone, condition, characteristics, type, axial, cardioid, omnidirectional,...
R&D Report 1966-22 : The Standard Telephones and Cables Type 4126 microphone. H.D. Harwood This report describes tests on five samples of the type 4126 capacitor microphone made by Standard Telephone and Cables Ltd. It is a miniature version of the type 4108 instrument but employs a field-effect transistor instead of a valve in the head amplifier. Power is supplied by means of long-life batteries in a small case which may be situated up to 100 ft (30m) from the microphone. The frequency...
Topics: frequency, microphone, type, microphones, characteristics, axial, specimen, impedance, specimens,...
R&D Report 1957-10 : Some experiments on the subjective effect of limiting the upper frequency range of programmes D.E.L. Shorter, W.I. Manson, E.R. Wigan To obtain first-hand knowledge of the subjective effects of high-frequency band limitation, some tests have been carried out with Research Department staff of various categories as observers (thirty-four in all), using twelve types or recorded programme material. Low-pass filters having nominal cut-off frequencies of 10 kc/s and 12 kc/s...
Topics: observers, filter, frequency, observer, programme, experiments, filters, band, material,...
R&D Report 1954-23 : The Neumann microphone Type U47 H.D. Harwood, R.J. Packer A new directional electrostatic microphone, type U 47, produced by the firm of Neumann in Berlin, incorporates the capsule originally designed for the type M 49 microphone but uses a cheaper form of head amplifier. The U 47 microphone is designed to give either cardioid or omnidirectional polar response. Frequency characteristics, sensitivity and noise have been measured on a single specimen for both conditions....
Topics: microphone, omnidirectional, cardioid, characteristics, condition, output, neumann, frequency,...
R&D Report 1955-24 : The Stephens electrostatic microphone Type C-1. D.C. Derham Laboratory tests have been carried out on a single specimen of the Stephens Trusonic Microphone, Type C-1, a pressure-operated electrostatic instrument which functions by amplitude-modulating a radio-frequency carrier. Measurements of frequency response, sensitivity, variation of sensitivity with mains voltage, impedance and susceptibility to interference from magnetic fields have been made; the stray...
Topics: frequency, microphone, stephens, transformer, circuit, demodulator, impedance, electrostatic,...
R&D Report 1954-40 : The Telefunken microphones Type Elam 200 and Elam 201. W.I. Manson, D.E.L. Shorter, H.D. Harwood, J. Nash, R.J. Packer Tests have been carried out on specimens of the Telefunken electrostatic microphones type ELAM 200 and ELAM 201. The ELAM 200 microphone is pressure-operated while the ELAM 201 can be switched to give either omnidirectional or cardioid characteristics; identical pre-amplifier arrangements are used for both types. The usual measurements of frequency...
Topics: elam, blam, microphones, sensitivity, microphone, omnidirectional, cardioid, frequency,...
R&D Report 1962-41 : The Sennheiser Type MD 82 and Electrovoice Type 642 microphones. W.I. Manson The Sennheiser type MD 82 and Electrovoice type 642 are both directional microphones in which sound is received through openings along a narrow tube. Type MD 82, a number of which are in use in the Corporation, is no longer in regular production but is included in this report for comparison with the currently available type 642. Measured frequency characteristics and polar patterns are given.
Topics: type, microphone, frequency, microphones, directivity, electrovoice, impedance, bass, sennheiser,...
329
329
texts
eye 329
favorite 0
comment 0
RCA Review 1955 Sept
Topics: circuit, rca, frequency, oscillator, figure, tube, equation, noise, detection, cathode, rca review,...
R&D Report 1982-06 : Digital standards conversion: comparison of colour decoding methods. C.K.P. Clarke A number of PAL and NTSC decoding methods, several of which involve comb filters based on line delays, are compared, primarily for use in standards conversion. To simplify comparisons, the circuits are all converted into a general form consisting of a chrominance-pass filter, a subtractor used to obtain luminance and a chrominance demodulator. The theoretical performance of each circuit...
Topics: chrominance, luminance, frequency, signals, subcarrier, decoding, vertical, pal, circuit, sampling,...
R&D Report 1992-06 : An example of a phase-segregated enhanced PAL broadcasting system. M.G. Croll, J.O. Drewery, J.E.Easterbrook, R.Storey, G.A.Thomas An enhanced PAL system is described which is fully compatible with the terrestrial broadcast system B/G, having a 5 MHz bandwidth. Elimination of luminance/chrominance cross-effects is achieved using the principle of phase-segregation which also allows enhanced luminance resolution. The source picture has a 16:9 aspect ratio and appears on...
Topics: frequency, luminance, chrominance, pal, signal, phase, horizontal, vertical, letterbox, filter,...
R&D Report 1956-20 : The Neumann electrostatic microphone Type KM.54. W.I. Manson, J. Nash The Nuemann KM.54 is a small electrostatic microphone with nominally cardioid characteristics. Tests were carried out on a single specimen and the results of measurements of frequency response, sensitivity, noise level and susceptibility to magnetic fields are given in this report.
Topics: microphone, frequency, output, shield, cardioid, axial, response, frequencies, voltage, impedance,...
R&D Report 1954-29 : The design of the LIP microphone Type L2. H.D. Harwood, R.J. Packer, R.A. Ticehurst A new lip microphone of the "noise-cancelling" type has been developed, having properties basically similar to those of the type L1 but incorporating a number of improvements. The problems peculiar to this type of instrument are analysed and the construction, performance and special features of the new design are described. A large number of production models has given...
Topics: microphone, type, frequency, ribbon, magnetic, breath, noise, response, acoustic, ambient, breath...
R&D Report 1965-34 : The Neumann KM64 microphone H.D. Harwood This report describes tests carried out on the latest capacitor microphone, type KM64, manufactured by Messrs, Neumann of Berlin. The microphone has a cardioid directional characteristic and is of the end-fire type design. Measurements have been made of the frequency characteristics for sound incident at various angles; the degree of interference from wind, with and without a windshield, and from magnetic fields has also been...
Topics: microphone, noise, frequency, characteristics, measurements, magnetic, type, neumann, sensitivity,...
R&D Report 1954-39 : The Nordwestdeutscher Rundfunk-Hiller electrostatic microphone Type M59. J.R. Chew, D.E.L.Shorter The M 59 is an electrostatic microphone of exceptionally small size and of nominally cardioid polar characteristics. Tests on a single specimen are described in this report. Frequency characteristics and figures for sensitivity, noise level and interference from magnetic fields are given, together with the results of a listening test.
Topics: frequency, microphone, electrostatic, baffle, sound, interference, magnetic, characteristics,...
R&D Report 1954-20 : AKG microphone Type DYN 60K. W.I.Manson Laboratory tests have been carried out on a single specimen of the AKG microphone type 60K. Measurements of frequency response, sensitivity, impedance and susceptibility to interference from magnetic fields have been made and are described.
Topics: microphone, frequency, dyn, response, magnetic, oooooo, akg, impedance, characteristics, output,...
R&D Report 1961-12 : AKG electrostatic microphones Types C26 and C28. H.D. Harwood, J.R. Chew, R.L. Deane, R.J. Packer This report describes tests on two electrostatic microphones manufactured by the Akustische und Kino-Gerate Gesellschaft (A.K.G.). The first, type C26, has omnidirectional and the second, type C28, cardioid characteristics. The microphones are of small dimensions and provision is made in each case for introducing an extension piece between the capsule and the head...
Topics: type, microphone, capsule, extension, interference, impedance, characteristics, frequency, noise,...
BBC Monograph 56: Stereophony: the Effect of Interchannel Differences in the Phase/frequency and Amplitude/frequency Characteristics. D.E.L. Shorter, W.I. Manson.
Topics: frequency, interchannel, image, characteristics, channels, width, difference, phase, bbc,...
Bell System Technical Journal, 43: 4. July 1964 pp 1533-1546. Design of Wideband Sampled-Data Filters. (Golden, R.M.; Kaiser, J.F.)
Topics: filter, frequency, bilinear, continuous, transform, transformation, transfer, filters, wideband,...
Bell System Technical Journal, 4: 4. October 1925 pp 586-626. The Sounds of Speech. (Crandall, Irving B.)
Topics: vowel, frequency, records, characteristic, amplitude, frequencies, speech, sounds, characteristics,...
R&D Report 1954-13 : The Klein-Plessey Ionophone loudspeaker. J.R. Chew A novel type of loudspeaker, known as an "Ionophone", has been tested. In this loudspeaker the conventional vibrating diaphragm is dispensed with and the sound is produced by a modulated r.f. corona discharge. The device is used in conjunction with a horn radiator and its main field of application is therefore in the high-frequency range; smooth response can be obtained up to at least 20 kc/s. In its present...
Topics: frequency, ionophone, horn, distortion, output, tuning, loudspeaker, axial, corona, overload,...
R&D Report 1965-32 : Beyer microphone Type M160 W.I. Manson The Beyer microphone type M160 is of the ribbon type and has a directivity pattern which is nominally a cardioid. Two specimens have been tested and the results of measurements of frequency characteristics, sensitivity, impedance and susceptibility to magnetic fields are given. One specimen was retested after extensive operational use and its performance found to be substantially unchanged.
Topics: specimen, frequency, microphone, impedance, sound, incident, directivity, characteristics, angles,...
R&D Report 1966-32 : Sennheiser MKH 404 and AKG 628 microphones. H.D. Harwood Two new capacitor microphones, the Sennheiser type MKH 404 and the Akustische und Kino Gerate type 628, have been produced which employ transistor circuits and radio-frequency polarizing of the capsule; both have a cardioid directional characteristic and are of the end-fire type. Measurements of the frequency characteristics have been carried out for sound incident at various angles; the degree of self-generated...
Topics: mkh, type, sennheiser, akg, impedance, frequency, noise, microphone, microphones, circuit, akg...
