Spectrum Analyzer Mac
For Mac OS X, Snow Leopard & Lion.
Available on the Mac App Store
Only USD$1.99 
Also available for iOS Devices
Sound You Can See !
Sound View is an Audio Spectrum Analyzer & Spectrograph App. It analyzes sound from the built in microphone, or from the Line in input device, and displays the results in three separate views.
The waveform view displays the raw input signal as a continuous wavy line, where each wave is a pulse of sound.
The spectrum view displays the frequency distribution as vertical bars, each bar represents a group of frequencies, the height indicating the strength of those frequencies within the audio signal.
The spectrogram view displays a two dimensional view of audio spectrum frequencies, over time. Each pixel represents a group of frequencies, it's color indicates the strength of those frequencies. The vertical rows represent different frequencies, and the horizontal columns represent time.
Frequencies range from 0 hertz to 22050 Hertz or 22K, this is half the sample rate of 44100 audio samples per second. That is the same sample rate as a compact disc audio recording.
Since it uses the microphone, it works well with iTunes. Any sound the mic can pick up is analyzed and displayed, so you can play music on your computer, or use a different sound system and see the frequency distribution, spectral density, and waveform.
Full screen display is available for each of these three views. Select the View menu item, then Full Screen Display, or you can use the Command-F keystroke. This will put the key or active window into fullscreen display mode. You can return to the windowed view by hitting the escape key.
In the waveform view, you can dynamically adjust the display width and height. The spectrum view allows similar adjustments, but you can also drag the display left and right, to see the frequencies that interest you.
The spectrogram view has controls for color intensity, and vertical zoom. It also allows you to drag the display up and down to see desired frequencies.
What's New in Version 1.1.0
- Enhanced for OS X Lion. You can now go to fullscreen mode with the OS X Lion window gadget, as well as the Cmd-F keystroke.
- Enhanced App Security. SoundView now uses the OS X App Sandbox for app security. SoundView will not be misbehaving.
- Minor Bug Fix. Waveform display in milliseconds was incorrect, it is now accurate.
Recording a Spectrogram
You can record a spectrogram for later viewing too. By selecting View -> Recording Control Panel you can start and stop recording and save your data.
Both the Spectrogram and Waveform information is saved to a jpeg image. The saved image can be quite large, the dimensions are: Width, 20 pixels per second of recording. Height, Spectrograph height + 100 pixels for waveform data, + 28 for caption text.
An 11 minute spectrogram has been successfully recorded on a MacBook Pro with 4 Gig ram, it handled it easily.
Preferences, Waveform & Spectrum Views
By selecting SoundView -> Preferences from the main menu, the following panel is displayed.
For the Waveform View, You can also choose any color for the waveform display. Also you can check whether or not to have the waveform view launched at startup.
For the Spectrum View, you have a number of options to choose from.
The Fast Fourier Transform Algorithm selection, allows you to choose between our algorithm for determining the heights of each spectrum bar, or the OS X Accelerate algorithm. The OS X Accelerate algorithm, is included in Apple's Accelerate Framework on your mac. Both algorithms perform very well, but do have slight differences in their output. Give them both a try !
The Number of Spectrum Bars selection, allows you to select from 8 to 1024 spectrum bars in the display.
The Spectral Flames checkbox, turns on and off the fire. An image of a flame is scaled for appropriate height for each spectrum bar.
The Upper & Lower Spectrum Color selections allow you to spread color over the height of the spectrum bars, for a great looking effect.
The decay rate slider allows you to control how fast the bars fall back to the bottom of the display. The control gives you full control, as the far left will let the value bar fall immediately, and the far right will not allow it to fall at all.
The autostart checkbox allows you to start this view at Sound View startup.
Preferences, Spectrogram View
For the Spectrpgraph View, you have a number of options to choose from.
The Fast Fourier Transform Algorithm selection, allows you to choose between our algorithm for determining the heights of each spectrum bar, or the OS X Accelerate algorithm. The OS X Accelerate algorithm, is included in Apple's Accelerate Framework on your mac. The Spectrum View and the Spectrograph View can use different FFTs, so set the options to your preference.
The Width & Height selections allow you to control the spectrograph resolution. Choose from 128 to 1024 on each selection. The Height selection is passed to the FFT, like the number of bars field is passed to it in the spectrum view.
You can customize the color range, by selecting your own color preferences for the base, first, second, and peak color plateaus. These color selections spread their gradients in a linear fashion.
The autostart checkbox allows you to start this view at Sound View startup.
Help
Application Help is availble from the main menu under the Help item, and also from the help button on the preferences panel.
Enjoy The App !!
