ページ1に含まれる内容の要旨
SCHNEIDER DIGITAL MICROPHONES FOR HIGH RESOLUTION AUDIO
DIGITAL MICROPHONES FOR HIGH RESOLUTION AUDIO
1
MARTIN SCHNEIDER
1
Georg Neumann GmbH, Berlin, Germany
schneidm@neumann.com
Microphones with digital output format have appeared on the market in the last few years. They integrate the functions
of microphone, preamplifier, and analogue-to-digital converter in one device. Properly designed, the microphone
dynamic range can thus be optimally adapted to the intended applicati
ページ2に含まれる内容の要旨
SCHNEIDER DIGITAL MICROPHONES FOR HIGH RESOLUTION AUDIO principle to P48 defined in IEC61938 [6], but adapted to Some of the requirements on digital microphones [8] the lower voltage and higher current requirements of later realized in the AES 42 standard [9] were ADC components. It already featured a gain ranging - physical layer interface & protocol ADC, to be discussed later, and limited remote control compatibility: AES3 protocol with overlaid functions (pre-attenuation) but yielded su
ページ3に含まれる内容の要旨
SCHNEIDER DIGITAL MICROPHONES FOR HIGH RESOLUTION AUDIO The essential requirement then for digital microphones settings n might be as high as -100…-80 dBu, and is pre remains to integrate A-to-D conversion providing seldom published in the specifications. One sees that dynamic range and resolution comparable to their high preamplifier noise is higher or lower than the above quality analogue counterparts. mentioned microphone self noise of -120 dBu-A, and one main task for the recording eng
ページ4に含まれる内容の要旨
SCHNEIDER DIGITAL MICROPHONES FOR HIGH RESOLUTION AUDIO diagram for digital microphones is shown in Fig. 5. The noise n approx. 7 dB higher, yielding -133 dBFS-A. ADIn dynamic range is vastly increased, especially for the Adding a real condenser capsule, the thermal/acoustical small gain values often used with condenser capsule noise n adds another 3 dB (-130 dB-A). This caps microphones, and most importantly becomes means that the thermal/acoustical noise n of the caps independent of the
ページ5に含まれる内容の要旨
SCHNEIDER DIGITAL MICROPHONES FOR HIGH RESOLUTION AUDIO higher frequent white noise components. One possible unavoidable physics, and the maximum allowed sound way to reduce this effect is a non-linear network, pressure levels cover the vast majority of applications. keeping both ADCs always in operation, and summed, For very loud signals, the dynamic range of the capsule depending on the signal level, as shown in Fig. 9 & 10. output and thus of the complete digital microphone can be shif
ページ6に含まれる内容の要旨
SCHNEIDER DIGITAL MICROPHONES FOR HIGH RESOLUTION AUDIO they are bound to find wide spread use. As the signal is [11] Microtech Gefell, Brochure: “MV230 digital - transformed with a high-quality AD conversion to the Digital measurement microphone”, digital domain, it is now also possible to obtain high- www.microtechgefell.com quality recordings with comparatively inexpensive, semi-professional recording equipment, if it does allow [12] Schoeps (2006), Brochure: “CMD series”, 24 bit word
