Plug for a microphone

August 30, 2016 8:07 AM

I just got a microphone with a cord that has a three-pronged male plug at the end. This won't fit into my amp, and I can't figure out what kind of plug I'd need. "Mic converter" turns up iPhone accessories and "preamp" looks like another, larger piece of equipment. What do I need to plug my mic into my amp?
posted by pxe2000 to Media & Arts (10 answers total)

That's called an XLR plug, or "mic cable" plug. Your amp probably takes a 1/4" "instrument cable" plug. here is an XLR to 1/4in converter. I can't speak to whether your microphone needs anything fancier than that (eg phantom power, etc) so I can't guarantee it will work for you. But XLR is a term you should use in searches.
posted by aimedwander at 8:10 AM on August 30, 2016 [2 favorites]

aimedwander covered the basic solution, but what type of amp are you trying to plug it in to?
posted by drezdn at 8:17 AM on August 30, 2016

This may be what you need.
posted by erebora at 8:44 AM on August 30, 2016

Yup, XLR. Music shops tend to stock them, and I've had reasonable luck with amazon as well. Just make sure you get the appropriate gender. N00b Phredward has noticed male for input and female for output, so erebora's cable is probably what you want (with an additional small -> large headphone adapter).
posted by Phredward at 8:57 AM on August 30, 2016

If it's like most microphones I've dealt with, something like this would work, or if you just wanted the adapter here's a female XLR to male 1/4 Stereo.
posted by drezdn at 9:45 AM on August 30, 2016

Best answer: If your amp is e.g. a guitar amp, or similar kind of amp, it's probably a high impedance input (or Hi-Z for short). That means you'll want one of these:

link

This should boost the signal the amp receives from the mic.
posted by billjings at 9:56 AM on August 30, 2016 [2 favorites]

An XLR signal is a "balanced" signal -- two wires are the same signal out of phase, the third is a ground; it is possible your amp can handle a balanced 1/4 trs (tip-ring-sleeve) input, which is the simple cable adapter you mostly get when you ask for an XLR to 1/4" adapter. But, this is not necessarily the correct adapter.

You should properly use a balun impedence adapter, which gets the electrical signals all routed correctly. (the link isn't an endorsement, just examples of what you want to buy). This takes the balanced signal (three wires) and converts it to the usual guitar-amp-cable style tip-and-sleeve "unbalanced" two-wire 1/4" connector. This is the same sort of signal your microphone input on your computer or phone would like to see.

Also, as someone mentioned upstream, your XLR microphone may require phantom power; you can get those many places for around $30, but be aware that low prices come with higher noise ceilings, so you might have a slight hiss or hum underneath your sound.

Edit: billjings has it right.
posted by AzraelBrown at 9:58 AM on August 30, 2016

Nthing Billjings has it.
posted by soundguy99 at 10:16 AM on August 30, 2016

Response by poster: drezdn: I'm plugging it into a Vox Mini3.
posted by pxe2000 at 10:31 AM on August 30, 2016

Based on the Vox Mini3 manual, it seems to be expecting an unbalanced High-Z input like a guitar, which means you should use a balun to match signal and impedance; don't use the cheap adapters with the 1/4" tip-ring-sleeve (looks like a stereo headphones) because then you're going to have a weak, probably distorted, signal.

The balun should be mounted as close to the amp as possible, e.g. don't plug it into the mic and then use an unbalanced mic cord to run to the amp; run an XLR cable to the balun, and plug the balun into the amp if it'll fit. Also, that amp won't provide phantom power, so make sure your mic doesn't require it.
posted by AzraelBrown at 11:33 AM on August 30, 2016