Unnatural noise (AT3060)

[JohnnyPraze]

I recently bought a used AT3060 mic.

I hooked it up today to check it out and left it sit for about 10 minutes for the tube to stabalize (as stated in the instructions) and when I went in for a test I got a whole bunch of noise. The kind of fuzz you hear when something is turned up too loud.

The noise is constant. When I speak in the mic my voice sounds clear and fine but you hear a constant backround noise. Its very prominent.

Also, the level meter in my DAW is bouncing around some?

I'm pretty sure its not a ground issue.

The noise also goes up and down with the gain almost as if there is too much but the noise is there even at minimal gain.

Could the mic or tube be bad?

Any ideas???

[JohnnyPraze]

Here is a clip of the sound...

[Kiwiburger]

Can't play the mp3 atm but It's most likely a failing tube. Probably the reason the last owner sold it - sucker.

I would suggest that your next post be something like "what's the best sounding tube for an AT3060" ...

[Thumper]

I heard that the tube in those mics is about the size of a pencil eraser. don't know how many different replacement tubes you're going to find.

how's your phantom power? measure it with a voltmeter, and see what it's doing. Check it out on a different pre or something to see if the problem moves with it.

[JohnnyPraze]

I tried that. Its definately coming from the mic.

Yes the tube is very small. Its a little over an inch long and a little wider then the width of an average ink pen.

[squeegybug]

Originally Posted by JohnnyPraze

The noise is constant. When I speak in the mic my voice sounds clear and fine but you hear a constant backround noise.

Could the mic or tube be bad?

Likely it is the tube. They often make "whooshy" or crackling noises when they are failing. Here's some information about that tube, looks like this?




"The tube is a hand-selected, pre-aged, subminiature Raytheon 6418 triode. Mounted near the bottom of the mic, it is connected by whisker-thin wires soldered to a PC board below it. The rest of the amplifier components, voltage converters/regulators for the plate and filament (and output XLR) are on this board. To prevent tube microphonics, the peanut-size triode is surrounded in foam and shock-mounted in a brass block."

This is somewhat similar to the M 149 approach. A little challenging to replace, it's not just a plugin. The tube itself shouldn't cost over a few $, if you can solder and have some fine tools it can be done, else you might want to check with AT for some service options.

Steve