Questions about Audio, amps, and computers

[blyloveranger]

I have not yet graced the ranks of a DIYer for audio, but I am hoping that dream may soon come true.

I thought I had the perfect project to begin working with amps and audio. I have been working on building my own Arcade cabinet and needed an amplifier for it. Plus since the fidelity didn't need to be great since the source audio wasn't spectacular and the speakers not great, it seemed like a good idea and first project until my head exploded from reading about amplifiers and hooking them up to computers and pre-amps and...well and everything.

I guess my question is do you need anything before an amp to hook up to a computer. I don't really understand what "comes out" of the soundcard from a computer, except that you can plug a standard cable into my card, and music comes out of my headphones. So, for instance, is a DAC needed before I go to an amp?

I have other questions, but most of them I think I can solve through reading once I understand the fundamentals of the problem that I am trying to solve.

I hope the question isn't to general to answer.

Patrick

 

[thomas997]

From the soundcard out of the computer you shouldnt need any sort of preamp. You could put one in there if you wanted (to adjust: tone, bass, rumble, phase adjust, etc.)

You may need to tweak the gain to get a good range of volume, assuming your using a stereo pot on the input...

It is a good project. I would be worried most about ground problems or loops cuasing humm in the speakers which would be annoying. So be sure to have a good star ground and add any filters if necessary..

 

[blyloveranger]

Thanks for the speedy reply Thomas. I have been reading so that my next step of questions might be a step up.

I am planning on using a stereo pot to control volume without going thru a pre-amp. Your reply affirming that conviction. After a bunch of reading, it seems to me that a GainClone or an OpAmp would be a good starting project. (The OpAmp idea came from the ESP website Project 76, so I am not actually sure if that is a good cheap option as there doesn't seem to be a lot of extra literature or comments on the amp).

Now my question: Are either of these projects reasonable and reasonably cheap beginners projects? The speakers are pretty cheap car stereo speakers so to me that says that I wouldn't need a very powerful Amp to run them, correct? For Example, a LM4780 chip-amp would probably over-kill, correct? Thanks for your help again.

Patrick