Ron’s Blog

DIY ‘ audio mastering at home’ is a tricky and complex process that takes years of experience to do it right. We all know your recordings can (and should) be mastered, and you have a home. But you can’t master your recordings at home. You can try, but you won’t end up with master quality results. First, briefly let me explain what CD mastering is. It is optimizing an already mixed stereo recording, so that it sounds as good or better in comparison with other CD’s or music of the same genre. It also means matching your songs on the disk so they all sound compatible with each other using very expensive and precise mastering equipment worth thousands of dollars. Software plug ins or a generic mastering preset are just not satisfactory to get the professional results for an artist that commands the attention of a music publisher, major label or retail record distributor in today’s competitive music market. Now the first step for mastering a song is to be equalized, then compressed. The compression stage brings up the average level so the song sounds louder, and then perhaps a final EQ stage to optimize the frequency contours. Is this easy to do? No way! The technical processes are easy enough, but to get it right is very difficult indeed. The chances are that you will end up with something worse than you started out with. In professional practice, music mastering is done by specialist mastering engineers. They spend their time doing nothing else and at times will master typically two projects in a day. Over the years, they gain a fantastic wealth of essential experience that you simply can’t gain at your home or from a home recording or mastering studio offering these type of audio services. And believe me there are a lot of them out there on the web promising professional results, but most projects end up with amateur sound or sub standard quality. I know, I often have to fix these problems. If you are really serious about getting the best from your recordings before you release them on CD, then you should pay for the services of a “pro” mastering engineer. That will be money well spent and less of a headache.

As long as your preamp is of professional quality and working properly, there is nothing about it that will prevent you from making good recordings.

Preamps really don’t matter anywhere near as much as many popular recording myths suggest. Your speakers are important, the acoustics of your room are important, your microphone selection and positioning are important, and your skills and are important. The microphone preamp usally comes after all of that in order of importance.

But still, you might have concerns about your preamp, and one of them is noise.

The correct way to set preamp gain is to increase it to whatever value that is necessary to achieve a good strong reading on the meters of your recording system, without clipping or distortion.

But you may find that when you do this, there is a lot of background noise.

This may be the acoustic background noise that is present in the room. Raising the gain of the preamp does raise this, but only in proportion to the signal you want to record. So the signal-to-noise ratio from this source of noise stays constant.

But it might also be that the noise generated by the preamp itself increases. This should not happen. In fact, many preamp manufacturers quote their noise levels measured at maximum gain, because this is where the signal-to-noise ratio is greatest.

So here is a simple test…

1. Set up a microphone up in a quiet room and set the gain on your preamp to maximum. Make a recording of the background noise of the room. Now save it as recording #1
2. Lower the gain of the preamp by 20 dB. Make another recording. Save that as recording #2.
3. Normalize both recordings in your digital audio workstation so that they are the same level.

Now, there are three possibilities…

* If the noise levels are about the same. In this case you can stop worrying and get back to recording.
* Recording #2 is noisier than Recording #1. This is normal. As above, stop worrying.
* Recording #1 is noisier than Recording #2. This is a distinct warning sign that something is wrong with your preamp. This simply should not happen.
Perhaps it may be time to look into a better quality pre amp or the unit you have may need repair or calabration.

Of course, I have only discussed pre amp noise level at high gain settings. But at least in this simple test, it is possible to see whether if your preamp is working properly.

I hope this helps.

Ron