The actual submitted question we are using for today’s Tech Tip was quite long, but the gist of it is as follows:
“I have a SoundBlaster Live sound card in my computer, but no matter what I do it seems to always have some low level static or hum in the background when using it. I have a MIDIMan card in another computer that works great. I realize the converters in the SoundBlaster may not be as good as the MIDIMan card, but should it be getting static and hum?”
Putting sound cards of all types and quality ranges inside of computers has always been tricky. There is the potential for a great deal of EMI and RFI inside of computers and it will impact the audio quality of your card. Both static and hum are somewhat common with these systems. This is why so many of the more expensive systems have all of the D/A and A/D conversion taking place outside of the computer. You have two variables you need to resolve in your system: the computer and the sound card. I wouldn’t be surprised to learn that your SoundBlaster card is more susceptible to a computer’s interference than the allegedly higher quality and more expensive MIDIMan card. On the other hand I wouldn’t be surprised if one of your computers was putting out dramatically more interference than the other. Swapping the cards is an easy way to test to see where the problem really is.
You can work with shielding inside of computers to reduce the amount of computer noise that gets into your audio. We’ve had tips about this in the past so feel free to search the archives for more detail. Ultimately the best solution is to get a system that uses an external interface for audio connections. Not only will you find it much less susceptible to its environment, but it will probably just sound better all the way around.