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Nessie Microphone from Blue Microphones

Blue cat in colored pencilI bought the Nessie Blue Microphone for less than $100 from Amazon.com and tested it today. Setting it up is a breeze. You just plug it into a USB port on your computer, open the Control Panel > Sound and tell your computer that you are using Nessie for recording. It has settings for recording the voice, musical instruments, and raw mode. If you record in voice or music mode the device does some processing to eliminate distracting sounds plosives (popping P sounds), rumbling and vibrations, and sibilants (harsh sounding consonants). It automatically adjusts to variations in the level of your voice. It has a built-in feature that reduces latency (delay) to zero if you are monitoring your recording through headphones. It also is mounted on a shock absorbing stand, and it is a one-piece device. If you want to do all the processing after you record,you can record in raw mode.

I opened Audacity and recorded several minutes of audio. I definitely have a voice for silent movies, but it did by far the best job of recording my voice of any of the many mics I have used, even better than my $275 Yeti Pro.The built-in pop filter is an awesome feature. I definitely give this great, inexpensive microphone, my unqualified recommendation.

Workflow for Removing Noise with Audacity

Suggested Workflow for Removing Noise with Audacity

In Audacity you can remove any kind of unwanted noise using the Remove Noise effect. These noises might include the popping sounds recorded when pronouncing the letter “p” or “b”, the sound of an air conditioner running in the background, the sibilant sounds often picked up when pronouncing the letter “s,” etc. In this brief tutorial I will detail a noise removal workflow I developed from my experiences in removing extraneous noises from hundreds of audio clips. I am assuming that the reader is familiar with the basics of Audacity, a free audio editing program. If you have never used Audacity, or need a refresher, I posted a tutorial covering the basic features of the program at this website: http://irt.austincc.edu/Audio/ . Let’s get started:
1. Import a clip into Audacity, using File > Import Clip or by holding down Control (Command on Mac) + Shift + I on a Windows keyboard.

2. Play the entire clip, noting the areas where there is noise. Vertical lines (|) indicate noise, usually created when the person who recorded the clip recorded the letter “p” or “b.” Figure 1 below shows what noise created when recording the letter “p” typically looks like.

3. Zoom in on the timeline to get a better look at the noise you want to remove by pressing Ctrl + 1 on the keyboard twice.

4. Select the first area with noise you want to remove. Don’t select only the noise. Select a second or two or audio before and after the part with the unwanted noise.

5. Press the space bar or the Play button and listen to the area you have selected. If the noise was created when pronouncing the letter “p” you should hear a “pppp” sound.

6. Select only the noisy area this time and listen to it. Areas of noise created when recording spoken speech are usually “p” or “b” sounds. As stated in Step 5, noise associated with the letter “p” will usually sound something like “ppppp.” Often when we record the word, between, you will hear something like “twtwtwtw.”

7. Now, we are ready to remove the noise we selected. In Audacity this is a two-step process.
7.1 From the menu at the top of the Audacity interface select Effect > Remove Noise. 7.2 Select Get Noise Profile. 7.2.1 Usually we want to reduce the noise by 24 DB (decibels) 7.2.2 Set the Sensitivity to 0.00. 7.2.3 Frequency Smoothing – 520 Hz is the default. Usually we don’t need to change this. When you
remove the noise and listen to the cleaned up area if it doesn’t sound good you may need to adjust this setting. 7.2.4 Attack / Delay Time – 0.00 is the default. I never adjust this setting. 7.2.5 Click OK.
7.3 Select Effect > Remove Noise again. 7.3.1 Do not change any settings. Click OK to remove the noise. The area that had noise should now be flattened.

8. Scroll through all the other areas of the sound wave or wave form that have noise and repeat Steps 4-7 to remove them.

9. Zoom back to the normal view of your clip by pressing the Ctrl + 2 keys or View > Zoom Normal on the keyboard.

10. Skip to the start of the clip by clicking on the Zoom to Start button ,, or by selecting View > Zoom Normal on the menu and listen to the entire sound clip again.
11. Remove any areas of noise you might have missed when executing Steps 4-7.

12. Select the entire clip by pressing Ctrl + A on the keyboard or by selecting Edit > Select > All on the menu.

13. Now, we are going to normalize the clip. Normalization boosts the sound to the loudest decibel level possible without clipping, or truncating, the highest sounds in the recording. From the menu select Effect > Normalize. 13.1 Accept the default settings. 13.2 Click OK.

14. Listen to the entire clip again to make sure it sounds good.

15. Sometimes when we normalize an audio clip we introduce additional noise. If this is the case, follow steps 4-7 to remove it.

16. The final step is to export the clip as an MP3 file. 16.1 Select File > Export or press Ctrl + E on the keyboard. 16.2 Save your clip in the location where you wish to store it. 16.3 It is a good idea to follow a systematic naming convention that makes it easy to identify what you have done to each clip. For example, I give my edited audio clips file names such as: Module_2_Slide_1_Edited.

NOTE: When I insert images into this post they are unrecognizable. You can view the document with the images inserted at this site:

http://irt.austincc.edu/Audio/noiseremovalworkflow.pdf

Guide for Buying Audio Equipment

If you just want to record your voice to add audio to your PowerPoint presentations, or perhaps to your lectures, you don’t need to buy much equipment, just an inexpensive microphone and headphones, perhaps a headset mic. You can turn your computer room at home into a decent recording studio by buying a few mobile panes such as the ones used for office cubicles and arranging them around it. You may like to convenience of having a small voice recorder to carry around with you, but our smart phones now do a pretty good job of recording the voice. This is the best online guide I could find for buying audio equipment for recording the voice:

If was put online by someone named Clark who is not related to me. Guide for buying audio equipment: http://www.ljclark.com/audio/audio-01.htm .

Recording Voice Memos on Your iPod

If you have an iPod Classic, Nano, or some older models, you can record voice memos. The Nano, 5th generation, has a built-in microphone. If you have the Classic, as I do, you can buy an inexpensive microphone that plugs into the dock connector on the iPod. I think the one I bought cost about $15-20.  You can also buy one that plugs into the headphone jack on your iPod. Before recording plug the microphone into the dock connector or the headphone jack.

1. Press the Menu option on the wheel device until the Voice Memos option appears.

2. You should see an option that displays “Start Recording“. Roll the wheel to select it.

3. A blue light should appear on your microphone, indicating you are ready to record.

4. Hold the iPod and mic a few inches from your face and speak into it.

5. At this point you can resume recording or save your recording.

6. Your recording should be listed, with a name similar to 3/20 8:30 am. You will have to plug headphones into the headphone jack of course to listen to your recording.

Calibrate Your Microphone in Camtasia Studio 8

Several years ago I wrote a tutorial on recording and editing digital audio in Camtasia Studio 8 and put it on the Digital Audio website (http://irt.austincc.edu/Audio/) . I am writing a more comprehensive tutorial for Camtasia Studio 8 which I should finish this summer. I just finished writing the section on calibrating (setting up) your microphone to make certain you are ready to record audio.

Calibrate Your Microphone

You should calibrate your microphone before recording to make sure it is ready to record audio and that it will record at the proper volume. You use the Audio Setup Wizard in Camtasia to accomplish this task. Plug a microphone into the microphone jack or a USB port on your computer. To calibrate your microphone:

  1. Choose Tools from the menu bar at the top of the screen, and then select Voice Narration.
  2. The Voice Narration dialog box opens. If the green horizontal bar is blinking in the area under “Source: Microphone” you should be read to record. Click the Start Recording button and speak into your mic.

3. Press the green Stop button to end the test recording. Save your file if you wish and press the space bar to listen to it. If you like the way it sounds you do not need to open the Audio Setup Wizard.

4. It is good practice to run the Audio Setup Wizard, though, and test your microphone. Click the Audio Setup Wizard button to begin the process.

5. If your microphone is not selected under Audio Device, click the down arrow and select it. Under Recording Source choose Microphone. Click the Next button.

5.1 Click the Auto Adjust Volume button.

5.2 Record the text blurb, “Since the Internet…”

5.3 If the input level is green, you are recording at a good volume level. If the top part of it is red, you should lower the input level or move away from the mic. When you are satisfied with your recording click the Finish button. You have completed the Audio Setup Wizard and are ready to record your voice narration.

My tutorial has several screen shots which I cannot copy and paste into this posting. I will post the link to the tutorial when I finish it

Total Recorder

Total Recorder is a versatile audio and video recording software program distributed by High Criteria. It is available in four editions: Standard Edition, Professional Edition, VideoPro Edition, and Developer Edition. The VideoPro and Develop Editions allow you to record, edit, convert, and play sound and video files. The Standard and Professional editions are designed to meet all your needs for working with audio.

Total Recorder supports the following audio formats: RIFF-WAV, Ogg Vorbis, FLAC, APE, and AAC within MPEG-4 and 3GP container formats. Total Recorder can record any sound passing through your computer’s sound card, and you can listen to the audio being recorded. You can record sound from a microphone, and external LP, cassette, CD/DVD player, radio, etc. You can also record sound from a digital source such as an Internet broadcast without having to plug special lines into your sound board, and with no loss of quality. You can convert media data to any format it supports.

It also allows you to edit your audio without any loss of sound quality even when you are editing compressed data. The program has other powerful features such as a time shift tool, the ability to split recordings on separate clips and on separate files, support for cue sheet files, tag support, a display timestamp, and it allows you to perform several operations on playlists. You can also apply normalization and fading effects and do batch processing.

You can download a free trial version of Total Recorder at: http://www.totalrecorder.com/productfr_tr.htm .  You can purchase a license for the Standard Edition for $17.95. A license for the Professional Edition costs $18.00 to upgrade from the Standard Edition. It costs $36.00 to upgrade to the VideoPro Edition from the Standard Edition, and $46.00 to upgrade from the VideoPro Edition to the Developer Edition.

Things Audacity Can’t Do

I have been using Audacity, the free digital audio recorder and editor, for a long time. It’s a great program, but there are some things it can’t do, such as:

  • It can’t record or play files in the MIDI format.
  • If you want to play or export files in proprietary or restricted file audio formats such as WMA (Windows Media Audio) or AAC (Advanced Audio Coding, supported by iTunes, iPad, iPod, YouTube, and others) you have to download and install additional plug-ins.
  • It has less plug-ins and effects that a specialized Digital Audio Workstation (DAW).
  • It can’t apply sound effects in realtime. You have to record the track and then apply sound effects to it.
  • It isn’t a specialized audio editing software package. There are some limitations on multi-track editing and mixing features.

Despite these limitations Audacity is a powerful and easy-to-use application that probably will meet the needs of most people who want to record audio, do some basic editing, and add special effects to it. Please contact me if you have any questions about it.

Getting Started with Digital Audio – What Equipment do I Need?

You need very little equipment to record digital audio. You will need a computer with a sound card. Unless you are a professional musician, or have some other special need, the sound card that came installed in your computer will probably work fine. Don’t even think about using the built-in mic on your computer or laptop or notebook computer for recording. The sound quality of your recording will be terrible. For $20-30 you can probably buy a desktop or headset microphone that will be adequate. I have aBlue Snowball Microphone Blue Snow Ball mic I bought from Amazon.com for $79 that I record a lot with. The audio quality of my recordings is pretty good, and my voice sounds natural. I also have a Sennheiser headset microphone I bought from Amazon for $170. I hate to have to admit this, but the Blue Snowball mic is just as good. If you have a microphone that did not come with a stand, you should buy one because you have to keep your mic steady to get a decent recording. That’s really all you need for recording audio except for a free software program such as Audacity for recording and editing. If you own an Apple computer it came with the Garageband audio program installed and it’s much more than adequate for anyone except a professional studio musician.

Getting Started with Digital Audio – What Equipment do I Need?

You need very little equipment to record digital audio. You will need a computer with a sound card. Unless you are a professional musician, or have some other special need, the sound card that came installed in your computer will probably work fine. Don’t even think about using the built-in mic on your computer or laptop or notebook computer for recording. The sound quality of your recording will be terrible. For $20-30 you can probably buy a desktop or headset microphone that will be adequate. I have a Blue Snow Ball mic I bought from Amazon.com for $79 that I record a lot with. The audio quality of my recordings is pretty good, and my voice sounds natural. I also have a Sennheiser headset microphone I bought from Amazon for $170. I hate to have to admit this, but the Blue Snowball mic is just as good. If you have a microphone that did not come with a stand, you should buy one because you have to keep your mic steady to get a decent recording. That’s really all you need for recording audio except for a free software program such as Audacity for recording and editing. If you own an Apple computer it came with the Garageband audio program installed and it’s much more than adequate for anyone except a professional studio musician.