Mic preamps

bachelorb

Cowboy Chord Virtuoso
I see some things on mic preamps here. Up until now, I've always plugged directly into the mixer. What are the advantages to using a preamp?

If you do use one, are they mostly used on condenser mics???

I have an old M-Audio Audiobuddy that I used to plug my mics into when I used the computer. Is this a serviceable preamp?

As always..... thank you,

Brad
 
Hi Brad,
If you're plugging microphones in via XLR and have a gain knob, you're already using a preamp.
Most mixers will have x no. of preamps built in.

The audiobuddy is, indeed, and standalone preamp and may or may not be better than what you're using.
Usually the best way to integrate a standalone preamp is to feed it into a line-level input.

Preamps aren't exclusively associated condenser/capacitor microphones.
Microphone preamplifiers are designed to amplifier any dynamic/ribbon/condenser microphone's output so that it's useful/healthy at line level.
Converters, and many outboard effects, usually operate at line level, so the preamp is the go between for microphone and these devices.

There are those who will plug some kinds of microphone straight into a line input. I don't.

Asides from the basics, preamps often offer additional options such as phantom power, polarity reverse, high/low cuts, pads etc which can be useful.
 
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It's perhaps worth expanding on the phantom power thing: condenser mics usually need a 48v supply to operate. As a rule, portastudios and computer interfaces don't often provide this so a standalone preamp can very useful for powering them in that situation.
 
Just to explain in a different way:

All mics need preamps to bring their relatively low level signal up to the level that mixers, recorder and everything else runs at.

Devices that were designed to plug a mic directly into have mic preamps built into them. Your mixer, your interface with the mic inputs both have preamps built in.

TheRE are a couple reasons to use a stand alone mic preamp:
1. You want to plug directly into a unit that only has line level inputs
2. You want a different flavor/quality of preamp than your mixer/interface has.

But as long as your equipment has a dedicated mic input, you don't need an external preamp to make it function properly.
 
I've never thought that any of the expensive boutique preamps they try to sell you on Gearslutz had any appreciable euphonic coloration at all compared to what you get recording on a good tape deck. Consider that they didn't even exist before the 90s, and the engineers just used whatever was in the board. But you do need something if you want to plug a condenser into a Portastudio
 
Most of the boutique preamps are (or are designed after) the preamps in those large consoles that they were just plugging in to.

There is a pretty obvious difference in sound between an app preamp and a neve preamp and a grace preamp. That tape changes the sound more is debatable.
 
The Tascam preamps are fine. Generally if there's a trim knob, there's a preamp.

For years I used an AkG 414 with a standalone 48v power supply pluged into the 1/4 inch input with great results.

So you can let go of the gas ......for a little while. :D
 
Just like to add (ref RFR) that there are now plenty of phantom power units around for $30 or so. This means that you may not need a fully fledged pre amp to use a capacitor mic on a portastudio etc. In fact even if the incumbent PS pre is a bit noisy the extra output of a cap' mic can help a lot.

Couple of caveats? Some PPower boxes are crap. I bought two that do not deliver anywhere near the specification 10mA* though they were at least silent. A second, single channel unit was up to spec.

Also, older gear can have low headroom, it was designed for dynamic mics after all. Might be an idea to get a couple of inline XLR 20dB pads?

*Now, all you tape guys are practical types and ALL own a digital multimeter, don't you? I shall post a phantom power test regime in "Contributions" shortly.

Dave.
 
Thanks guys.... I'm not looking at buying anymore preamps. I was just wondering if using one would give me any more flexibility.... It sounds like the answer is no.....
 
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I find that a good FET preamp reduces noise at high gain. A good tube preamp adds a lot of color/harmonics and tend to be nice for recording bass DI and on some vocals. That's about it, so if that's worth it depends. If you don't use mics that need gain I'm not sure you need an expensive pre, but if you do, a homerecorder should only need 1 good one. Anything more is probably GAS unless you're going to be recording other people for $.
 
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