My sound output failed. Help

[charlesphillips012]

After spending days on end working on the show my computers sound output failed and i have no way of getting any sound from my computer to my amp. i am using a 1100watt amp and 4 massive speakers (3foot by 2foot with 2, 15 inch speakers in each one) to put on a show for about 200 people. I do have access to up to 3 other computer but non of them have the software on them.

[dgrant]

So, did your sound card fail, lose a driver or a driver update cause it to fail? Sound cards and motherboard sound devices are usually pretty good these days.

[Max-Paul]

several options. 1) you do realize that your lic. is good for 5 seats (computers). So if you have only loaded the software on one computer. You can load it on 4 more still. 2) Most computers now days have the "sound card" built into the mother board. But usually you can go into the bios and disable the on board sound and get a sound card for the computer. Might be other options, but I am not thinking of them at this time.

Any reason you think the sound chip got zapped. Did you see a spark as you plugged in the lead to your amp? If so, may I suggest that in the future, have power turned off of the amp and computer. Maybe I would also suggest a isolation balum just in case there is a potential difference between the computer and amp.

[scubado]

What is an isolation balum? Is it the same thing as running a ground wire between the two cases?

[Max-Paul]

Maybe I used the wrong name. This would be a transformer that has a 8 ohm impedance in the input stage to match the output of the sound card in your computer and the output impedance would match the input of the amp. Most important is that if there is any kind of voltage difference between the two, it would be blocked in the balun (transformer). I believe the definition of a balun is that it is an impedance transformer.

I hate when I forget how to spell something I have not seen in years. So, I really wanted to spell it as balun, not balum.

[scubado]

Does this go back to the days of tube amplifiers? Never heard of a need for something like this in consumer electronics. Maybe in concert situations?

[viennaxmas]

It is still in use quite a bit - those are pretty much small transformers to electrically isolate or to adapt impedance. It was used a lot in concert situations - most mixers are microphone inputs only, so everything line level needs to be run through a transformer to make it match - in this case they are called DI boxes (Direct Input). In a lot of scenarios they are also used to break up ground loops.

This type is also used if you need long cable runs in audio as well as for public address systems.

For the purpose of this discussion, I think the suggestion is to put a transformer in the audio line for electrical isolation between the equipment outdoors and the computer, which in general is a good idea for protection (as I had to learn the hard way this year where a ground loop smoked my DMX adapter).

[Max-Paul]

ah jim is just trying to bust my chops. But I am not the one with a fried sound card that was connected to a large amplifier. Ground loops are a bugger and what if the amp is floating and has a charge on its ground in reference to the computer. Isolation transformers make this go away.

Hey Jim