A little off-topic, but CRAZY!

[mazeroth]

This does have to do with speakers so bear with me...

I'm going from my computer to my Sonic Impact T-Amp. On the back of the T-Amp is a 1/8" stereo jack. If I pull the stereo jack out a little under halfway while music is playing, it takes the vocals out of the recording, and I can hear background vocals plain as day. With the plug like this, if I move the balance to the left, it plays left output on both speakers...if I move it to the right, it plays nothing but right output on both speakers. Why is it doing this, and better yet, HOW! It's an analog signal...I don't see how it can perfectly take out the vocals and let the instruments to play through perfectly? It's not like it's taking out a set frequency range. On a couple of songs I've done this to, it's only taken out the lead vocals, and left the background vocals perfectly intact. A lot of the time the background vocals have a lot of echo to them.

I had this same experience back in the late 90s on my Pentium 100. While playing an Alice in Chains CD in my CD-ROM I accidentally hit my computer, causing it to do this same thing. I could hit it to undo it, and hit it again and it would kick back in (not 100% of the time...sometimes it took a few hits hehe).

Anyhow, sorry if this is off topic but I figured you guys would know how this is happening.

Thanks!

[karma]

your removing the ground on the rca when u do that.

you can do that with a 2 channel amp by instaling left and right + output two one speaker. nothing new

[Cal Weldon]

I don't have a clue why it's happening. That once that happened to me but it stopped when the drugs wore off. I wonder if anyone else has had this happen?

Also, there are "off topic" and "everything else" sections you can post this kind of thing in.

Cal

[karma]

lol yes in. Everything Else

[SY]

Originally posted by karma
lol yes in. Everything Else

And, like magic...

[mazeroth]

karma, that worked! Pretty neat stuff LoL!

[Enzo]

Your stereo plug has the left and right on the tip and ring contacts, with the sleeve(shaft)as common. WHen you click it in half way, one side gets grunded and the other side contacts the one inout contact. What that amp channel sees is the two signals in series, but they are at opposite phase relationship.. Before the nitpickers hit me, the polarity reversal also reverses the phase of one side relative to the other. SO things panned to center - where vocals almost always are - and in phase side to side - as vocals almost always are - will cancel. But parts of the music that differ between channels will essentially be unaffected.

So the vocals cancel out and disappear. but the left and right stuff sums together and you get what you heard.

If you ever see an ad in the back of the magazine for vocal eliminators, that is all it is, one channel is inverted and they are summed together, neatly cancelling out the vocals. It's an old trick.