I struggled over the last month to clean up the audio quality of my voice recordings. Specifically, I have a book project that I’ve been working on for over a year now. The project is moving into a fund raising stage and I needed to record a quick intro of myself setting up a short story version of the book and then a closing that is something between a call to action for a pledge drive for the book and a chat with the author.

The problem I had is that despite having a relatively new computer, and an awesome recording microphone (Rode Procaster) I was getting some kind of white noise in the background of all my recordings. Now, I could successfully record with any of my noise cancellation microphones that I use with Dragon Naturally Speaking and in a pinch or a hurry these are also my goto tools for quick and easy screencasts and tutorials.

For an intro to what is a very high quality audio book however, they sound tinny and cheap. So I had to dig in and figure out how to get some better results. To achieve this I did a whole lot of trouble shooting on my own and even got several pro tips from my good friend and business partner Joe Klein of New Media Creative. Joe by the way is also the voice over artist speaking on my book and the producer of the overall audio book. He’s got almost as much experience as I have years on the planet. When he’s recording his own stuff, there’s never any issue, but in this case I needed to do the recording and he lives a few thousand miles away.

After I finally achieved a cleaner recording sound, I realized that my laundry list of audio clean up tips might be useful for other people, so here’s my list. Maybe some of these will help you!

Audio Clean Up Tips

  • First I tried every microphone I had from my best to my worst. In all cases I still got some white noise in the background. The noise cancellation microphones had the least, but I think the noise canceling aspects of the mic were just reducing the volume on the noise not elliminating it and they were also having a very slight negative impact on my own voice.
  • Next I tried using a usb sound card instead of the mic input to my typical laptop sound card. I’ve had an external usb soundcard for this type of situation for quite sometime after buying an ultra laptop years ago (different than my current machine) that had a very poor sound card in it.
  • I have a Tapco 10 input mixing board. My Rode Procaster has an XLR plug and I have a very high quality cable that plugs into XLR in the Tapco mixer. I’ve got 2 XLR plug options there and experimented relentlessly with different settings, different levels of gain etc on the mixer with the output going out of the 1/4″ phone jack to a 1/8″ converter to the 1/8″ mic input on my laptop. No luck
  • I have a xlr to usb converter as well that bypasses the mixer all together. This thing like many of xlr to usb converters is cranky. It seems that some days I get clean sound out of it and other days I do not. When I first took it out of the box I had to glue the gain nob back on. (bad sign) It’s only gotten less reliable with age. From what I’ve read through online reviews of many different brands, many xlr to usb converters tend to be very brittle finicky things. I’ve never dropped mine, but it came with the nob off and maybe UPS or fedex or Amazon packing handled that oversight for me.
  • Getting more serious, I went around the house and identified every electronic device on the same circuit as my laptop and mixer (when I was using it). I then proceeded to unplug everything on that circuit, especially things like refrigerators and fish tanks, both for their juice and possible electromagnetic interference as their external sound interference from fans and running water.
  • We have lots of hard tile floors, which doesn’t make for a good audio recording environment unless you are going for an echo chamber in a large hall type of sound. So I pulled shades down wherever I could covering glass windows.
  • I grabbed piles of fleece blankets and draped them over furniture in my recording vicinity and put throw rugs down on the floor.
  • It’s been cold here some days so before I start recording, I take my laptop outside and sit it on a table and let it run outside for 10-15 minutes in the cold. I’m literally chilling my laptop so that my fan if it is running will stop and so that it will be chilled when I bring it in so that it won’t kick in too fast if at all.
  • I put my laptop on one table and my microphone and mixer on another table.
  • I make sure my laptop is plugged in so that power saving features do not kick in and mess with the processor mid recording. Same thing goes during editing and rendering of the final file!
  • I take two dining room table chairs and stretch another fleece blanket over their backs, and I place these between the table holding my microphone and the table holding my laptop. This is to block any processor or fan noises coming from my laptop should it make noise. It also helps block mouse or typing noises if I have to scroll through a script or if I’m doing a screen cast.
  • Some of those last items made significant improvements in the quality and probably got me about 40% of the way to my goal, but the big one was going into recording settings on my laptop and disabling the check box that gives control to any program (such as my recording program) plus, I turned down the microphone boost option to ZERO and turned down the mic input levels on the laptop to about 40%. This then makes the mixing board settings the main source for input levels. I can’t turn my computer to 0% but I definitely can’t have this digital setting higher than 40%. Still dabbling through trial and error with even lower settings but I’m not seeing a big return in this effort.
  • Finally, on my particular mixer I have an RCA (red and white plug like on the old VCRs) and instead of going from the normal Aux out to the 1/8″ adapter to my laptop mic input that I mentioned above, I instead use an RCA adapter that plugs directly into my mic input (this was a suggestion from Joe whose never physically seen my setup and options, but had the keen insight that I might get cleaner output out of this cable and from RCA in particular. He was right. This helped a lot. In retrospect, I think the 1/8″ adapter from the 1/4″ phone jack might be a weak link along with the very flimsy male/male cord that runs from the adapter to my microphone input. As a result I’ve ordered 2 new cables from Art Pro Audio via Amazon. One is a XLR to USB cable, no adapter just the cable and the other is a usb to T connector (aka 1/4″ phone jack plug). These will hopefully open up 2 new audio clean up options for me. One a direct connection from my microphone to my usb plug, no mic input at all. The other being a direct connection from my headphone jack on my aux output of my mixing board. Those last two cables are still being shipped, but with everythying else I’ve done already the audio is a whole lot cleaner!

Hope that might help you, if you are at your wits end, looking for some tips to clean up noise in your audio recordings. In addition, I’m also going to take these lessons learned and see if it helps improve my Dragon Naturally Speaking transcription results too!

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