Signal Inspector is a Mac OS X application that was created to suit my needs when doing some audio electronics work. It consists of a number of signal generation and analysis tools with simple interfaces.
Included tools are:
- Spectrum analyzer with variable size FFT.
- Spectrogram (waterfall) with selectable dynamic range.
- Oscilloscope with one channel and basic trigger capability.
- Level monitor with peak and average readings.
- Tone generator with sine, square, triangle, and sawtooth waveforms.
- Noise generator (currently limited to white noise)
- Pulse generator with control for rise and fall time.
The application uses either the built-in audio hardware or external USB sound cards and supports most sample rates and resolutions.
Somehow the oscilloscope trigger functionality has stopped working. This was due to a change in the core DSP library. The issue has been resolved and a fix will be included in the next release. A temporary workaround is to send the same data to all channels of the device selected in the oscilloscope.
For more detailed information about the progress of Signal Inspector please visit the news section.
Signal Inspector should work on any Macintosh computer running Mac OS X 10.4 or later.
Soundflower has been used successfully to patch audio devices internally, for example connecting a tone generator to a spectrum analyzer, and is recommended. Another similar system is Jack OS X. It is more complex but should work.
Signal Inspector is available as a universal binary which runs on both PowerPC and Intel based Macintosh Computers. Currently no localized versions are available.
Please understand that this is a development version so glitches and bugs are to be expected.
Any comments or questions are much appreciated. If you have found a bug please describe exactly what you did to trigger it. My email is email@example.com. Please allow me a few days for an answer.
License & Disclaimer
Please understand that this application has been developed as a hobby project on my spare time. I am a programmer, not an audio professional, and I do not have extensive knowledge of the instruments I have implemented. Thus I cannot guarantee the correctness of the behavior of the instruments or of the obtained results.
Copyright © 2008, Jens Lindblad. All rights reserved. Unmodified copies of this software may be freely distributed but not sold.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.