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Headphoneus Supremus
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As far as data acquisition goes (DAQ), its basically the opposite of a DAC so instead of Digital => Analog, it would be Analog => Digital. Most of the gear I work with is limited to 16bits, so a 24 bit DAQ would be amazing. When processing signals, a DAC would still be very helpful because we do the intial A=>D conversion and then manipulate the data. As you stated there is a lot of noise in the chain to obtain the analog signals so we need to filter, modify, and use other techniques to get rid of parts of the data or change it to something meaningful. We then output the data back to an analog signal so we still need to do a D=>A Conversion. At the moment that DA conversion is limited to 16 bits, going higher might be better. Since these signals are being perceived by instruments rather than human ears, the 24bit DAC would probably be put to good use.
OK, thanks, I have no experience of DAQs, just ADCs and DACs. I have no idea how a 24bit DAQ works or what sort of signals you will be feeding it. But you have to be very careful with audio DAC specifications. If you understood the original post of this thread you will realise that the only thing that bit depth represents is the dynamic range, the range between the noise floor and the maximum output level (technically the signal to noise ratio, SNR). When they advertise themselves as a 24bit DAC, all they mean is the digital word length of data they are able to accept, not the resolution they are able to output! So, 16bit represents a maximum SNR of 96dB and 24bit represents a maximum SNR of 144dB. But no DAC on the market has an SNR of 144dB due to the limitations of the laws of physics in a circuit, the actual SNR varies from model to model, so it may actually be possible to find a 16bit DAC that has a higher SNR (resolution) than a 24bit DAC! In other words, it would be relatively easy in theory to make a 64bit DAC. Just allow for the input of a 64bit word length, hack off 48 bits and output the remaining 16bits worth of resolution (SNR = 96dB). In my opinion the marketing of DACs is highly misleading because the advertised bit depth gives no indication of the actual output resolution. The best you can do is look as the Signal to Noise specification of the DAC, divide that number by 6(dB) and that gives you the digital output resolution (bit depth). One other thing to look out for: The S/N specification for DACs is given in dB but some manufacturers are very crafty and use an A weighted scale, which is entirely inappropriate and will could indicate a significantly lower S/N than implied by the specification. It is possible that a DAC with a S/N spec of 110dB actually has a significantly larger dynamic range (output resolution) than a DAC with an S/N spec of 112dB (A). Sorry, just another one of the myriad marketing tricks employed by the audio industry. Try if you can to get the S/N spec in un-weighted dB, otherwise the 6dB per bit calculation will not be accurate.
G