digital-audio.org
Information centre for all about digital audioDigital to Analogue
It all ends here!
Re-creating the Audio
At the end of its journey digital Audio ultimately must be turned back to analogue in order for our ears to hear it. This is as crucial a process as the original sampling that gathered the digital data. The hundreds of CD players from a few pounds to thousands of pounds are testament to the fact that sound quality varies enormously in the Digital to analogue conversion process. It is an unending engineering quest to improve the process.
So - how does it work?
Remember this picture from the A to D page? Well we have the digital samples so how do we re-create the wave?
Well a digital to analogue converter will process the samples and adjust its output over time for each sample value. The picture demonstrates the process, though its a little crude as in reality there are many more samples for a wavelength.
The result of the converter above is an analogue signal that looks like the image on the left. It's not quite yet what is required, so is subjected to digital and analogue filtering to smooth out the wave with the ultimate goal of getting as close to the original as possible.