Monitor hum from lcd screen

[Jburn34]

I've got an alesis ra100 amp and some mkII monitors, and an lcd flat screen for my computer.

When I crank the amp up it gets a really bad hum only when the lcd is on.

I've got them in different sockets but probably the same circuit. There really isn't a convenient way to run an extension cord or whatnot.

What is the easiest/cheapest way to fix this? I've got to keep the screen on to do the mix/editing.

Much thanks,
Jeremy

[Blue Bear Sound]

It's not the screen that's causing the hum - more likely the monitors power supply adaptor....

[SPINSTERWUN]

Blue Bear Sound is correct.......

Try plugging it in to a different outlet.

[Jburn34]

What do you mean? The power adaptor for the screen?

The amp powers the monitors.

Jeremy

[Blue Bear Sound]

The LCD Monitor - NOT your speakers!

[Jburn34]

Is there anything I can do besides change the outlet it's plugged into?

Thank for ya'lls help!

Jeremy

[Blue Bear Sound]

Try physically moving the computer monitor's power adaptor away from the amp or cable run...

[Jburn34]

Moving the power adaptor, the screen, the monitors, etc. does nothing for the hum. I even ran a long extension cord and plugged into a different outlet and I still got hum, maybe from something else though.

Its definitely the lcd screen/power supply causing the problem....when the screen flickers in and out it causes different hums...and when you turn it off it goes away completely....

There's got to be a box or something to run my power through to get rid of it...........what's it called?

Jeremy

[Blue Bear Sound]

Try the Ebtech Hum Eliminator...

[SPINSTERWUN]

Blue Bear, just gave you the correct answer.

You might also want to try using a three prong adapter, first, on the problematic device (there might be a gound loop problem).
If that doesn't work, then use the prescribed solution that was offferred by Blue Bear.

peace.....

spin

[Jburn34]

Blue Bear,

I just checked some of those out on ebay. Do I just run 1/4" speaker line through it or something?

I've got RCA going from my sound source (computer and Tascam 788) to the amp, then regular speaker wire going to the monitors.

Thanks ya'll,
Jeremy

[Blue Bear Sound]

That unit's not for speaker signals!!!!!!!!!!

It's for line-level only..... it's extremely unlikely you're getting hum induced on the speaker wire..................... now if these are powered monitors that's another story and you can use it on the line-level signal you're running INTO the active monitors...

But there's something not consistent about the wiring you're describing and the hum you're getting.... any hum you hear is more likely a ground loop issue in your line-level connections.

[Jburn34]

I've got two sources going to the amp via RCA...the computer soundcard and the Tascam 788.

I just realized that when I unplug the RCA coming from the computer, the hum goes away.

What gives?

Jeremy

[Blue Bear Sound]

Ground loop - likely from your computer's s/c...........

The Ebtech unit WILL fix this....... connect it between the computer and the amp.

How are you connecting the 2 sources to a single amp? (if you're using a Y-adaptor, that's a problem right there...)

[Jburn34]

I am...the amp inputs are 1/4", but both my inputs are RCA, so I just have a "Y" adapter that goes from 1/4" to two RCA for each channel.

Is there a better way?

Jeremy

[Blue Bear Sound]

That's a no-no.... you NEVER use a Y to fuse 2 outputs together - you should use a mixer, or a simple line-level switch-box.

You can use a Y to split 1 output into 2 outputs, but never the reverse (2 outputs to 1 input).

[Jburn34]

Ok...thanks for the info...wish I would have known that before...I guess I just need to get a simple switch box. Are they all about the same?

Jeremy

[Blue Bear Sound]

http://www.rdlnet.com/stmxmmx3.htm

or

http://www.rdlnet.com/rusx4a.htm

[SPINSTERWUN]

Bruce is DA" MAN.................

Peace....

[Blue Bear Sound]

No.... more like - DA BEAR!!!!!!