or Connect
Head-Fi.org › Forums › Help and Getting Started › Introductions, Help and Recommendations › What's the difference between a DAC and an Amplifier?
New Posts  All Forums:Forum Nav:

What's the difference between a DAC and an Amplifier?

post #1 of 12
Thread Starter 

I know what each does, but how does each affect sound? Which should I get first?

post #2 of 12

DAC converts the sound from digital to an analogue stream. The amp simply amplifies that sound. 

post #3 of 12
Thread Starter 

What effect does each have?

post #4 of 12

The ability to listen to the sound is the dac. To hear it at comfortable levels is the amp. 

post #5 of 12
If I read your initial post correctly, the answer (which to get first) IMHO is a loud, resounding 'it depends'.

Most headphone outputs on computers, CD players and whatnot leave a lot to be desired - they tend to be underpowered and often, especially in the case of computers/cheap sound cards, they also pick up a lot of noise.

You will probably find the sound quality to be noticeably better if powering your headphones from a dedicated amplifier. Note the 'probably' qualifier - it depends on what source your music comes from, how you currently drive your headphones, what headphones you have... Etc, etc.

A dedicated DAC may also help, but probably the significance will be less than what you get from the amp - at least based on my (very limited) experience.

There are also a number of quite affordable DAC/amp combos out there, giving you both options at once. :-)
post #6 of 12

What's the difference between a DAC and an Amplifier?

 

A Digital to Analogue Converter takes the 1's and 0's of the digital music and turns into an analogue waveform, in other words, the sound you can hear when played through a transducer, as notes or whatever. An amplifier then amplifies that analog waveform into a signal that can drive a transducer or speaker. A line out signal straight out of a DAC is mostly voltage, so assuming you can wire that up, it will be too loud, and dynamics aren't reproduced well enough because it has no provision for the current demands of a headphone or speaker. An amp does more than control the sound - that's the job of the preamp stage on the headphone amp - but like I said it amplifies the signal into one that can run a speaker or headphone.

 

Now a speaker or headphone will have current demands as well as voltage because of the physics that leads to it reproducing the analogue waveform into actual sound. For starters, its efficiency rating may require a certain amount of power to hit a volume level that a listener needs or prefers. At the same time, the nominal impedance that a headphone or speaker is rated at is just that, nominal - meaning it isn't always fixed at that imepedance level. If the transducer plays a bass note for example the impedance might drop, and ideally an amp should produce double that power at half the impedance to produce the proper transients. This ratio is more easily achieved in speaker amps because the range of speaker impedance is very narrow - mostly 6ohm to 8ohm, then some 4ohm, maybe 12ohm and 16ohm. With headphones it gets more complicated as they can range from 8ohm all the way up to 600ohm. This is why you might encounter for example some amps as "current-driven" designs, which is basically what speaker amps tend to be,* as opposed to ther amps that are voltage-driven. Now, it's not so much you only have just one, but it depends on how much more of the other. Typically low impedance means more current is necessary, but if your headphone is relatively less efficient, then it will require a lot of voltage still;  high impedance typically means it needs more voltage, but if it's efficient enough, then it won't need as much voltage. Such an amp might make more power at 300ohm than at 150ohm and 32ohm, but that rule about impedance and current doesn't apply in the same sense here.


*Marketing n speaker amps say "High Current" or a fancier version like "WRAT - Wide Range Amplifier Technology" which in some cases might not actually be a patented circuit design, but just a fancy way of saying "high current"

post #7 of 12
I think dac is for better and clear sound output
And amp is for giving full voktage to headphone/earphone thus it gives full sound.

Sent from my IM-A850K using Tapatalk 2
post #8 of 12

Pretty well stated above.  DAC converts the digital bit stream to analog AC.  Amplifier boosts or attenuates AC amplitude.

 

Which one to get depends on what you are starting out with, and which aspect of your setup is less capable at its respective task.  IE:  what headphones you have, what you are currently using to convert the bit stream to analog AC.  Macs for example have surprisingly  good/clean/robust headphone outputs for headphones less than ~50 ohms.

post #9 of 12
Thread Starter 

Sennheiser HD 429S on an Asus laptop, that's pretty much it. Gonna buy some flacs but mainly music from iTunes.

post #10 of 12
Quote:
Originally Posted by GrmanRodriguez View Post
 

Sennheiser HD 429S on an Asus laptop, that's pretty much it. Gonna buy some flacs but mainly music from iTunes.

 

Bad idea if you're purchasing off that laptop, or if you're syncing the iOS device where you purchase that music on that same laptop with iTunes. I updated to iTunes11 so I can sync my iPad (specifically, FLAC Player and PDF reader), and while listening with MediaMonkey, music stopped playing, and when I looked, one by one FLAC files in MM started greying out. I uninstalled iTunes11, and everything went back to normal. Reinstalled iTunes11, this time making sure it only associates with one (empty) iTunes folder like how my previous iTunes settings are, restarted the computer then loaded MediaMonkey...when it moved to the next track it won't play and again I can see my files greying out like I'm getting hacked in a Hollywood blockbuster. I ended up using my gaming rig to sync the iPad, despite the leptop being more for work, but at least I get my copies of academic journals through email anyway.

post #11 of 12
Thread Starter 
Quote:
Originally Posted by ProtegeManiac View Post
 

 

Bad idea if you're purchasing off that laptop, or if you're syncing the iOS device where you purchase that music on that same laptop with iTunes.

 

What's the bad idea? Get an amp/DAC?

post #12 of 12
Quote:
Originally Posted by GrmanRodriguez View Post
 

What's the bad idea? Get an amp/DAC?

 

Having iTunes and another ripper/player software on the same computer. Like I posted above, iTunes will hog all audio files, even the ones that it can't actually play, like FLAC. If it's purely for ripping, then it should work for ripping alone, but keep in mind that there might be other issues having iTunes hogging all the files.

New Posts  All Forums:Forum Nav:
  Return Home
Head-Fi.org › Forums › Help and Getting Started › Introductions, Help and Recommendations › What's the difference between a DAC and an Amplifier?