whats the difference between analog and digital electronics?

[castiron]

does anyone know the difference? like technically wise.

thanks

[Chaos]

Re: whats the difference between analog and digital electronics?

Digital components output either a high (on) state or a low (off) state w/ no other possibilities (think black or white).
Analog components turn on or off gradually (think shades of grey).

[PFDarkside]

Re: whats the difference between analog and digital electronics?

To simplify it, analog effects modify the signal itself, digital effects use an Analog->Digital converter to change the signal to the digital domain (1's and 0's), modify it digitally, then use an D->A converter to convert it back to analog signal.

A digital effect is only as good as it's converters, if the sampling and converting is done poorly the effect sounds chopped and digital. If the converters are high quality and using a high sampling frequency and resolution then there's at least a possibility of a nice sounding effect.

An analog affect is all electronic components that can actually change the signal itself. Think of a wah, it's just a bandpass filter with a variable center frequency, pretty simple from an eletronics standpoint.

[tone4days]

Re: whats the difference between analog and digital electronics?

PFD has alot of good info there .. to take it a step further, it is not just the converters, but also the analog filtering that takes place after the reconversion back to analog, that can determine how good the device will sound ... low quality components / poor design in that final output stage can ruin a good digital device's effectiveness ...

another thing that even the best circuitry / components can't change is the effects of phase destruction by digital circuitry ... see, a signal has amplitude AND phase information ... digital converters work ONLY on the amplitude component, all phase information is destroyed upon conversion to digital domain irrespective of the sampling rate and number of bits ... now, can people hear the difference? .. you have to be the judge for yourself

it does give me pause when considering rigs with high quality tube amps all perfectly tweaked that have digital effects in the effects loop ...

t4d

[Stevo]

Re: whats the difference between analog and digital electronics?

Considering audio, digital wave forms do their best to emulate analog wave forms. The digital on/off signals (1s and 0s) are used to create binary words - the more binary words you can get, the better the resolution: ex: 256k resolution is smoother than 128k resolution.

Here's an abstract: Visualize a stair case with 10 steps. Then visualize a stair case, with the same length, but with 20 steps.. then visualize a stair case at the same length, with 128,000 steps. The higher the amount of steps, the more the stairs look like a flat surface. This is the same idea behind calculus limits, as the count of steps get closer to infinity.

[tone4days]

Re: whats the difference between analog and digital electronics?

right stevo ... great analogy to describe the 'resolution' aspect of improving the information content as it represents amplitude (signal strength) ... of couse, this doesnt address the phase component, but it is certainly important ...

one thing i have not gotten my head around is the use of additional bits of encoding for recording and over sampling ... if it all gets 'downsampled' to 16 bits per sample @ 44.1 K samples per second, how are the extra bits per sample and extra samples per second used?

t4d