A/D convertors

[kikling]

What are these? Can someone help me out? I heard all about these but I still don't know what they do. If someone could explain in to me in easy, no technical words I would really appreciate it. Thanks
-Jack

[Jon X]

Analog to Digital convertors.... D/A is the other way, Digital to Analog. Goes in as one, comes out as the other.

Say you are recording with any digital device (computer, digital multitrack, etc), and you plug in a mic. Something has to convert the analog signal in that mic to a digital format (bits) for the recording device to understand, the A/D convertors do this. When you want to go from the digital device back out to an analog speaker (which most people have), then the D/A convertors come into play so that the speaker can understand what to do.

FWIW, Dragon has a cool glossary on the main page with some straight forward definitions for stuff like this. http://www.homerecording.com/glossary.html

[Cooperman]

An A/D converter converts an analog (electrical) signal into a digital signal (0's and 1's). In the case of audio, a line level signal is usally around couple of hundred millivolts (correct me if I'm wrong anyone). A computer doesn't know how to read this information being sent to it, as it doesn't undertsand the "language", because computers can only understand the digital "language". So to make the computer be able to understand what it's being it sent, the analog signal has to be converted into a digital signal - this way the computer can understand what it is being sent. Think of an A/D converter as a translator - your computer doesn't understand the "foreign language" it's being sent - so through an A/D converter - "the translator", it is able to make sense of the information being sent to it.

Hope this helps

[Layth]

There are others a lot more qualified then me to describe this but I'll take a stab. The A in A/D stands for analogue. As in the kind of signal put out by something like a guitar to an amp or a microphone or any amplified electrical device in this case that produces sound. The D stands for digital, and what happens is the analogue signal is turned into ones and zeroes, by the A/D converter, something computers can understand. Thats pretty much it but there is a wide range as to how well these converters do their job.

Layth

[c7sus]

What about bit length and resolution?

CD's are currently produced at 16-bit, 44.1 kHz resolution. This is the Red Book standard. Now, correct me if I am wrong, but I believe that the latest generation of 24/96 converters are the current DVD standard, and that 48/192 is already being developed.

What does this mean? Well, for starters, higher resolution means a much better approximation of the sine wave (your most common audio signal) but it also means you need tons more hard disk space to store all those bits of information. I read on this BB awhile back about the difference in file size between 16/44.1 and 24/96 and it is staggering!

Now I'll let someone else explain dithering....

[Recording Engineer]

Go to www.digido.com and learn away...

[kikling]

So where to I get these a/d convertors. are they expences. I do home recording with Cool Edit and i just plug my mic into the sound card. Is that the same thing as an a/d. I guess Im transfering a analoug signal (my mic) into a digital one (recording on the computer.) Thanks Alot

[Layth]

Yeah, your soundcard has built in A\D converters, but a pro version would be something like the Appogee Rosetta http://www.apogeedigital.com/products/index.html street price is about $1000 for 2 channels of sound.

Layth

[Track Rat]

Dither is our friend. Dither good.