Acoustic, analogue and digital

[vitaminman]

Hey,

Let's test your knowledge:

What is the difference between acoustic audio, analogue audio and digital audio, and what are some of the different devices that can produce them?

Nick

PS: This is REALLY REALLY easy, don't let scientific words fool you...

 

[Fade]

Oh great, you're get everyone to think. Ouch.

 

[HaZwaiOh]

dat, md = digital , 48khz?

 

[Barock]

acoustic audio = some ol' country guy with a guitar?

 

[MaximeRobin]

I may don't have the right word for it in english but here is my guess;
-acoustic; actual sound, sound wave
-analog; sound via change of electric intensity on a tape or others means
-digital; sound in informatic lauguage, 0/1, on any format.

 

[" Killah! "]

Ayo, I know dis ish here.

Akoostic: It be like, when my moms be like, yo Kill where be da WIC cheese, and I be like: "Shut up bytch, I be watchin' Springer."

I also is a rapper.

Analog: its what comes out your butt after you be eatin nasty burritos from da ghetto Mexican fast food joint dat be employin illegals. When da illegals get busted by immigration yo' food price be up like, a dollar yo. (Or quid, wutevah.)

That's a buck dat coulda bought me a King Cobra, yo. I ain't down wit' dat.

Digitals: Da phone numberz I be gettin' from shortys when I is drunk at da bar. Den u wake up da next da after bonin' and be like "shyt, yo, dat bytch be nasty."

You deal wif da hangover.


Rezpekt.

 

[BOSS AUTHORITY]

Analog: Based on continous base-10 system, which has an infinite number of possible values. Example: Old school synths like the Moog analog synth

Digital: Based on a discrete binary system, which has a finite number of values. Example: Pretty much everything made after the early 80's.

In other words, an analog quantity is a scalar quantity, and a digital word is a vector.

Acoustic: I think it's the actual sound wave travelling through the air. Example: Guitar

All 3 are mediums of audio creation.

 

[vitaminman]

Hey,

Looks like we have some smart people here after all...

Boss Authority: I'm not much of a maths person, but wouldn't ANY numbering system potentially have an infinite number of values? Base 2 (binary)? Base 16 (hexadecimal)? I thought all numbering systems could represent all numbers in different ways...

As for the scalar/vector thing... ? My understanding is that a scalar is a single value, like the number 4, and a vector is a series of values, like 1,2,3,4,5. Like in Illustrator, you can create a single point (scalar) or a line (vector).


Take care,

Nick

 

[BOSS AUTHORITY]

When analog values are represented as digital (converted to binary), each continous analog value is rounded to a discrete binary value (depending on how many bits are representing the value). That's why higher bit sampling represent the analog value more closely (less rounding). Picture a sine wave: Analog would be a smooth continous curve (ex. ~~~~), while digital (depending on number of bits) the curve would be made up of straight lines (ex. _-=-_-=-_). It's alot easier to explain with actual pictures. Hope this helps...

-BOSS AUTHORITY

 

[shayme]

A couple of finer points...

"Analog: Based on continous base-10 system, which has an infinite number of possible values. Example: Old school synths like the Moog analog synth."
-- BOSS AUTHORITY

Analog has NOTHING to do with a particular numbering system, base-10 or otherwise. Analog is theoretically continuous, but only to a point (all systems have quantization eventually, even if it is at the atomic level, or electrons temselves).

"In other words, an analog quantity is a scalar quantity, and a digital word is a vector.
-- BOSS AUTHORITY

The terms "Scalar" and "vector" do NOT apply to this discussion as far as I understand them. A scalar is a number, a vector is 2 or more numbers, which represent an amount AND a direction when taken together (as a vector). For example, speed is a scalar (20 mph), whereas velocity is a vector (20 mph, 30 degrees W of N).

Ultimately, digital audio can be represented as real numbers, with "infinite" variations (and many digital programs work with real numbers internally).

However, the real consideration should always be, "how does it sound", and "can I tell this is digital vs. analog" or "can I tell this is 32bit float vs. 16bit integer"?

Finally, consider photography. Film photography is analog (continuous), but it DOES INDEED have quantization, or "graininess"; for example, ISO 400 speed film is much "grainier" than ISO 100 film; therefore, ISO 100 pictures can be enlarged more effectively than ISO 400 without image degradation.

Analog recording is one form of representing the real world, digital another. They both have inherant strengths and weaknesses, but I would argue that digital can be (and has already been) pushed to overcome it's inherant weaknesses to be BETTER than analog, whereas analog can never be what digital can.


Shayme

p.s. Analog=good&warm; digital=bad&cold.

 

[" Killah! "]

Ok, let's get real. I guess I'm not all that funny as I thought I was.

Acoustic: sound's movement via pressure waves through a compressible medium i.e. air. This could be a trick question, because one can surmise that acoustic sound creation is the presence of an oscillation source that is not native to the digital or analogue realms. However, the study of acoustics itself implies that all sounds generated by an amplification source analysed within a compressible medium irregardless of that amplifier's oscillation source, as long sound is emanated from that within a tested compressible medium can be viewed as acoustics. Hence hydroacoustics, or psychoacoustics. Essentially acoustics imply sound perception via an eardrum and relay through the aforementioned compressible medium i.e. air, water.

Digital audio: a sound wave that is represented by samples which therefore represent air pressure at a series of successive moments in time.

Analog audio: pressure variations in the air captured by a microphone are represented as an electrical signal (voltage).

There I'm being more serious.

Shayme is right ANALOGUE= WARM AND GOOD. DIGITAL= COLD AND BAD. SATURATION OF TAPE IS "HOT" AND "IN" RIGHT NOW. It's also a type of natural compression. LEARN HOW TO USE A COMPRESSOR .

I like the "color" of analogue, don't you. Digital is sooo "transparent."

 

[vitaminman]

Hey,

Wow, a lot more answers than I expected!

Here is a REALLY simplified definition of the three:

Acoustic - describing an instrument that doesn't need electricity or electronics to generate its sounds. Example: a drum kit, saxaphone, piano.

Analogue - describing an instrument that does need electricity and electronics to generate its sounds. Example: an old synthesizer from the 70's.

Digital - describing an instrument that needs a computer chip or other integrated circuit to generate its sounds. Example: a sampler.

I stress that this is an oversimplification, please don't bombard me with contradictions...

So, if someone wanted to have a bass sound on one of their tracks, you could choose between one of three different basses: an acoustic bass (like the big wooden stand-up ones used in old jazz music), an analogue bass (like the ones used in old 70's funk), or digital bass (pretty much any synth bass from 1983+).

When you use an analogue synth, you are in essence generating the sounds from scratch by telling these little electonic components called oscillators to create a voltage and send them to your speakers. When you use a digital synth, your sounds are already pre-stored on a chip somewhere (in RAM on a sampler, in ROM on a device like the Triton). The sounds are not being generate from scratch; rather, they are being 'read' from memory.

With this is mind, it is completely possible to sample the sounds of an analogue synth, store them in RAM/ROM on a digital synth, and use them for later. When you play them back from the digital synth, they should in theory sound just like the analogue synth that made them.

So far we've only talked about digital synths as ones which store digitized representations of acoustic and analogue sounds. However, digital synths can also create new sounds from scratch as well! As a matter of fact, anyone who is able to read this post has a digital synthesizer right in front of them...a computer is, in essence, capable of doing anything that any digital synth or sampler is capable of doing.

If you have a wave editor like Cool Edit or Sound Forge (pc) or Peak or Spark (Mac), you can make cool sounds on your computer using their waveform generators. You can make the basic waveform shapes (like sine, sawtooth, triangle, square), noise (like pink, brown, white), and if you're clever enough you can make more complex waveforms by modulating one with another. Sound Forge is especially good for this, they have a simple FM synth which allows you to make sounds that were so common in the 80's.

Take care,

Nick