原创 关于测量DAC / ADC

关于测量DAC / ADC的文章，虽然是英文的

Rating plus Assessment regarding ADC / DAC





The ADC / DAC lies at the heart of the encoding section of a computer stereo process, and is most likely one of the most essential section in the overall signal chain. The ADC should discretely trial the analog transmission, assess the amplitude of the test, plus make up the rating as a binary term. Whilst conversions made with the ADC’s component—the DAC—can consequently be advanced for higher-fidelity playback, drawbacks brought in by the DACr will go with the music indication all the way through electronic processing and storage space and, at last, again into the analog status. Therefore, the particular selection of the ADC irrevocably influences the faithfulness of the caused transmission. For significant apps for example , the long term ongoing availability associated with traditional sound indicators, to the most effective degree achievable, the ADC ought to show sound visibility—which is, it will need to neither include to nor take away out of the audio. To evaluate the extent of transparency, the      power evaluations along with subjective aural efficiency, including the converter’s managing guidelines for example , selecting rate of recurrence and expression time-span, ought to be regarded. In the end, the signal-level source to the converter, converter-component model, and exterior issues like grounding and also protecting may significantly change the faithfulness of the resulting document.



Benefits



This is sometimes odd the fact while meaningfully clear sound indicators can be found simply in the analog area, these people are usually ideal saved by the electronic site. In addition, the needs of transforming sound indicators into the electronic site, and back again to the analog site, are probably by far the most tough within electronic sound products. In fact, the only procedures in the

finished sound signal chain which are usually much more difficult are usually the transducing of indicators from acoustical to electric, and again through electric to acoustical—that is to say, exactly what is accomplished through the mic and loudspeaker. The last paradox is which Edison together with several other sound innovators did not really need to deal with ADC and DACs, or perhaps mics as well as loudspeakers. His or her all-acoustic sound programs were “mainly natural.”



Presently, each time an analog documenting is transmitted to the electronic site, the ADC is definitely the critical element in the transmission route . The converter’s main functioning guidelines—sampling consistency and concept segment—identify the actual theoretical data transfer as well as sound flooring of the electronic saving and other sorts of conditions. Conventional sound converter proportions likeregularity results, distortion, jitter, and also linearity

1 This valuable statement had been created because of the roundtable discourse, “Aspects in Electronic digital Sound Preservation Preparing along with Supervision,” held before. The gathering has been organised.

2 can be implemented to examine a converter’s value. Issues like the effective of the prefacing filtration as well as helpful concerns like input transmission quality and also grounding and protecting are additionally critical. Selecting a good DAC must be dependant on a great examination of technological weighings as well as of very subjective being attentive. Countless cultural tracks have been documented with discount faithfulness; as an example, sound data transfer is pretty restricted and the sound floor is usually higher. For this particular purpose, a number of specialists claim that when transforming analog tracks with regard to electronic storage, the actual fidelity of the transmission chain can be of comparatively poor fidelity. Others claim that any digitization must use the best-possible signal chain to capture and preserve as much information as possible. Given that in any archival-conversion project, the cost of digitization equipment is trivial compared with the cost of labor, the latter approach seems more prudent. This passage requires the situation that an archival transformation signal chain must offer very high fidelity.



The purpose in choosing an ADC is openness—that is, to pick a device that neither adds to nor subtracts from the recorded sound. In other words, an ideal converter has no sound of its own. Converter transparency remains an elusive ideal. Only the best converters can procedure transparency. Most converters are certainly not transparent. For some non-crucial applications, transparency is not vital. But for essential applications— and the archiving of audio materials for long-term preservation is among the most critical—transparency is vital. This paper describes some of the factors that influence ADC fidelity and suggests methods that can be used to find the bestpossible DACs for critical audio applications.