Sub-60hz hum/rumble on a condenser mic

[boybianchi]

What might be going on:

1. I own the Rode-Nt1a as well. It is a relatively cheap mic. If you want no noise try buying a 1k mic.

2. On every device you are using, you are gaining the signal too much

3. Pops and clicks shouldn't happen. Watch your proximity to the mic. To close will produce a bass boost aka the proximity effect. Read the NT1a manual for more details.

A descent highpass filter (or filterS in series) can sweep away the subnoise.
If it ain't for professional use, i wouldn't sweat about it.

[MixBuss]

Sounds like a defective mic, try touching the metal chassis of the mic or the xlr connector, if the rumble is reduced it is probably an earthing issue.

[saltydog2012]

can you just roll it off with eq? sounds like your mic is busted but to be honest you probably dont need those freqs anyway. i wouldnt worry too much if you can roll it off.

[Gamelan]

Originally Posted by atothegreen

This might be a little advanced for this sub forum, but I'm not sure where else to put it since it seems so rudimentary.

I'm getting a weird low frequency hum/rumble on my Røde NT-1a that varies from 2-30Hz. There's also some concurrent broadband noise, but it's at a way lower level than the main rumble. It doesn't matter where I am, or what equipment it's hooked up to – tube pre, MBox, at home base or on mobile recording gigs.

At the same time, I'm getting clicks and pops when the mic gets hit with relatively high SPL. I had a similar issue with a TLM103 where the mic would short and cut out for about 10 seconds before recovering; in this case it just pops, often irreparably even after judicious use of the pencil tool.

WHAT is going on?

Are you using a shock mount? There's an awful lot of low end rumble that just comes through the floor or the ground and up through the mic stand. I live near a few freeways (LA) and the rumble is unavoidable even in the best conditions. Just means the mic is doing it's job of picking up the sound that is there. I've found various ways to reduce it including putting the mic stand on a heavy foam pad. But, it never totally goes away. Fortunately, there isn't much musical info in those very low frequencies, so a little high pass filter and it's good to go.