Adventures In Audio

If setting the gain correctly is so important, why don't mic preamplifiers have meters?

by David Mellor
FREE EBOOK DOWNLOAD ► LEARN AUDIO ONLINE ►

When you first learn how to use a mixing console, you will be shown how to set the gain. Your instructor - either in audio school or in the workplace - will emphasize the importance of this and kick your ass every time you get it wrong, until you can't do anything other than get it right.

Setting the gain correctly optimizes the signal level for further processing in the mixing console. EQ, inserts, auxiliary sends, routing, fading, solo and mixing all depend on having the right signal level for optimum performance, and the gain control is precisely where you set that.

But outboard microphone preamplifiers commonly only have rudimentary metering facilities - perhaps only a single 'clip' LED - or no metering at all! So how can you possibly set the gain correctly?

The answer is that firstly the preamplifier needs to be correctly designed with plenty of output level available. For example, the Manley Labs Mono and Dual Mono microphone preamplifiers can supply up to 30 dBV of output before clipping. That is one hell of a voltage in audio terms - almost 32 volts, compared to a normal operating level of around one volt.

Audio Masterclass Video Courses

Learn FAST With Audio Masterclass Video Courses

With more than 900 courses on all topics audio, including almost every DAW on the market, these courses are your fast track to audio mastery.
Get a library pass for all 900+ courses for just $25.

Manley Labs Dual Mono

It's probably fair to say that the Manley Labs Mono can drive any line input effortlessly so there is no need for metering in the preamp.

Where you do need metering is in the equipment you are driving with the preamp, probably your DAW via your audio interface. So a good procedure for setting the gain with the Manley preamp is to choose the lowest setting of gain and set the 'input attenuate' control to its least amount of attentuation, then increase the gain. When you are getting a good, healthy signal level with a reasonable margin before clipping on your DAW's channel meter, you have the right settings.

The Audio Masterclass Pro Home Studio MiniCourse

FREE MINICOURSE

Great home recording starts with a great plan. The Audio Masterclass Pro Home Studio MiniCourse will clear your mind and set you on the right path to success, in just five minutes or less.

Setting the attenuator and gain controls in this way will optimize the noise and distortion performance of the preamp.

Now since this is a tube preamp with variable 'character' according to the gain setting chosen, then once you have mastered setting the gain in the technically correct way, you are free to break the rules and, if you wish, choose a higher gain setting with more attenuation. This will give more of the tube sound.

By the way, some preamplifiers do have a meter. If it's an electro-mechanical VU meter then it's useless other than showing that there's signal present.

Tuesday September 29, 2020

Like, follow, and comment on this article at Facebook, Twitter, Reddit, Instagram or the social network of your choice.

David Mellor

David Mellor

David Mellor is CEO and Course Director of Audio Masterclass. David has designed courses in audio education and training since 1986 and is the publisher and principal writer of Adventures In Audio.

More from Adventures In Audio...

An interesting microphone setup for violinist Nigel Kennedy

Are you compressing too much? Here's how to tell...

If setting the gain correctly is so important, why don't mic preamplifiers have meters?

The Internet goes analogue!

How to choose an audio interface

Audio left-right test. Does it matter?

Electric guitar - compress before the amp, or after?

What is comb filtering? What does it sound like?

NEW: Audio crossfades come to Final Cut Pro X 10.4.9!

What is the difference between EQ and filters? *With Audio*

What difference will a preamp make to your recording?

Watch our video on linear phase filters and frequency response with the FabFilter Pro Q 2

Read our post on linear phase filters and frequency response with the Fabfilter Pro Q 2

Harmonic distortion with the Soundtoys Decapitator

What's the best height for studio monitors? Answer - Not too low!

What is the Red Book standard? Do I need to use it? Why?

Will floating point change the way we record?

Mixing: What is the 'Pedalboard Exception'?

The difference between mic level and line level

The problem with parallel compression that you didn't know you had. What it sounds like and how to fix it.

Compressing a snare drum to even out the level

What does parallel compression on vocals sound like?

How to automate tracks that have parallel compression

Why mono is better than stereo for recording vocals and dialogue

#