Digital vs Analog Uses

[Hyydrah]

Please correct me if I'm wrong.

 

From my understanding, speakers/headphones, etc. require an analog signal, so the DAC to the audio output device needs to be travelling as an analog signal.

 

Analog signals degrade more easily than digital signals do (digital signals do as well, hence the shielding at longer lengths).

 

Therefore, wouldn't it be more sensible to use a digital signal as much as feasibly possible? For instance, if I had a computer far away from a receiver, shouldn't I use a digital cable (ie. coaxial) from the computer to the receiver, and then an analog cable (ie. RCA) from the receiver to the speakers (since an analog signal is required) in order to minimize signal degradation? Of course, in some scenarios a coaxial cable isn't possible to use because of their poor malleability, but whenever it is and when a digital signal can be used, doesn't it make the most sense?

Edited July 6, 2013 by Dave Zember

[gts250ftw]

optical will be the best over a long distance

[Godlygamer23]

Yes. Digital signals are more ideal because of signal degradation.

[OddballMV]

I'm sure others will answer this better than me but you don't have the choice of using a digital or optical signal, both have to be done. Digital signals are converted into analog sound signals with no sound so they have to be amplified. You don't choose between one of the other.

[Hyydrah]

I'm sure others will answer this better than me but you don't have the choice of using a digital or optical signal, both have to be done. Digital signals are converted into analog sound signals with no sound so they have to be amplified. You don't choose between one of the other.

I should rephrase, when I say "use a digital signal" or vice versa, I'm referring to the cable such as a coaxial or RCA cable, not the internal signal in the components themselves. For instance, if I had the choice between using an RCA and coaxial cable, coaxial probably makes more sense because it transmits a digital signal (provided that malleability isn't an issue).

Edited July 6, 2013 by Dave Zember

[Godlygamer23]

Digital is better in the long run. It will hold up better for signal degradation, and less conversion needed because (if I remember correctly) it gets converted from analog to digital and then back to analog again, causing more signal degradation.

[Hyydrah]

Also, is there any noticeable difference in sound quality when an analog cable type is used in place of a digital cable type? I'd imagine that it depends on the length of the cables but at what point does it become apparent?

Edited July 6, 2013 by Dave Zember

[Godlygamer23]

Probably not to the average consumer.

[Hyydrah]

Digital is better in the long run. It will hold up better for signal degradation, and less conversion needed because (if I remember correctly) it gets converted from analog to digital and then back to analog again, causing more signal degradation.

Well from my understanding, it would be converted from digital to analog then back from analog to digital if you were to use an analog cable between your DAC and your motherboard.

[ShearMe]

On the end of any digital signal, you need a DAC (which is just a chip that converts digital to analog) and then an amplifier to drive the speakers (headphones count as speakers). There are many speakers with amplifiers and sometimes DACs as well built in (none with a DAC and no Amp) which are referred to as "Active" speakers. "Passive" speakers run off an analog signal from an amplifier. Technically, all speakers are passive, but when referring to an enclosed speaker unit you take into account everything inside the box.

 

There's a bunch of technical stuff for you to read at soundonsound.com if you want the details, but basically cable length doesn't matter in situations smaller than an NFL football stadium. Distance errors in analog signals appear as feint echoes. Digital signals are not prone to distance errors because the "feint echo" will not register as a valid voltage corresponding to a particular bit or word.

 

In a computer, all the audio signals are in a digital format. The optical and coaxial ports on your motherboard comes directly from these digital signals. The optical on a soundcard is sometimes processed but still completely digital before being sent to the optical or coaxial port on the soundcard. Digital signals are also sent to the Digital to Analog Converter (DAC for short) on the motherboard and/or audio card. Output from any DAC chip ever made has been "line level" or -10dBV for consumer audio. This means for practically any speaker ever made, we need an amplifier to make the signal stronger to overcome the resistance of the coil/magnet driver in the speaker. The analog outputs on the motherboard come from the amplifier on the motherboard.

 

There is no difference between analog or digital wires - any wire will perform just like every other wire made of the same metal and gauge (thickness). 

Edited July 6, 2013 by ShearMe

[I'm Batman]

optical is better in most of the senerios