Musician Gear & Tech Discussion

Is it normal for PA system to buzz when it's turned on? Just an airy hum sound... Any way to minimize? HELP

Kaleigh,
Does it buzz or hum when there is nothing plugged in?
60 cycle hum is usually caused by cheap transformers.
If there's no Mic or instument plugged in when you turn it on, then you've got an amp with a bad s/n, or a bad ground.
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S/n means "signal to noise ratio.
The signal is the stuff you want to hear - for instance, your singing.
The noise is everything else - hum, hiss, distortion, etc.
It's usually measured in percentage, your spec. sheet might say:
s/n .01%, or .05%, for example. For example: .1% is bad, .001% is good.
.
BUT - it may only be a bad ground. Flip the ground switch on the amp, if you have one.
If you don't have a ground switch on the back of your amp., then try this (if it's not a 3 prong plug):
1) Turn it off.
2) Unplug it.
3) Turn the plug around, and plug it in again. If it's a ground problem, that should fix it.
.
OK.
.
Now, if you only get the hum when you have a microphone or instrument plugged in, you might be picking up stray signals through your input cables.
What if you move the amp around to a new location?
Any difference?
And, if you squeeze the cable, does the hum get louder? If so, buy better cables, or a better microphone, and try it again.
.
If that doesn't stop the hum, then you need to get a noise filter.
I bought a rack-mount "Hush" filter. Between songs, there is dead silence.
Boss sells them, starting from about $80, I believe.
TRY it BEFORE you buy it. Some cheaper noise filters just chop off the high end, and rob you of all presence.
A filter range dial or range-select knob is a great thing to have.
Good filters allow you to change the threshold, which is - roughly - the volume level at which the filter engages itself.
You also want the option of something that'll change the release spead - fast or slow.
It's also nice to have the option of a mic. input, or a line unput.

Let me know what you find out.

Hey man, thanks for all the info, when I plugged in at my gig, it immediately was fine.. I think we just have dirty power at my house. You took a lot of time out I appreciate it!!

Kaleigh,
No problem.
It sounds like a bad ground.
If it happens again, just unplug the amp, flip the plug around, and plug it back in. That's all it takes.
Alan / Samick1

Make sure that all the connections are solid and that there are no loose connections, also new cables might be needed. old cables might be beat to hell and interfearance is caused by loose wireing. Not 100 % but its worth a shot!

I think the buzz is only in my head sometimes, but when turns out different, here's what I do:

- Look transformers, some make awful line noise/buzz - particularly laptops, CRT monitors, and TVs. Plug them into separate power strips AND then plug a 3-prong to 2-prong adapter onto power-strips-plug

- Uncoil extension cords

- Move transformers away from speakers and amps

- Take an aligator clip, and clip one end to your amp(s) ground and the other
to metal conduit or something metal that runs into the floor

Those are my hot tips - good luck!

mine was fading in and out (volume) when i ws playing some cd's this afternoon, I had the player hooked up through the tape input, I changed it to a 1/4 input and it seemed to work fine for awhile then the it started sounding like a homemade open air cassette recording from the early 80's

Any flourescent lights will cause a bad buzzing hum, if they're on the same circuit.

(We found this out trying to use Black lights on each side of the stage.)

Also make sure you have the right voltage fuses in it. I had to replace mine recently and noticed a hum. The voltage must be to specs, but the current density (amps) can vary - just keep in mind that a lower ampage means the fuse will blow more easily.

try this link:
http://www.prosoundweb.com/studyhall/ra ... round3.php

Stop toking it up!

LOL@IRMINSUL

I have an old PA, a Kustom 200W PA.

It's buzzes/hums. The only way I can get this thing to quiet down is to let it warm up for 15 minutes before I use it. Then it seems to be fine and LOUD!.

And always check the ground on cord/ outlet ground.

Yes, yes, yes. Check the ground. I played at a house party once, and by the end of the night, my lips were numb from the shock I kept getting from the mic!

Some would say that is part of the party beverages.

Wine, Women and electrical shocks. lol Maybe a lil Nitrous Oxide.. (j/k) lol

But electrical shocks for sure.