Measurement first results (entirely done with the Parallella)
image #1
- measuring my home-theater speakers during testing (still work in progress so I'll move to the hifi system only after thorough testing)
- microphone is close to the speakers so there is limited room influence
image #2
- measurement of logsweep 2 millions samples 10-21000Hz sampling rate = 44100
- the first vertical line represents a sinewave of 10 periods 11025Hz to determine where the logsweep signal starts exactly (because 10Hz is way too low for the speakers to reproduce anything)
image #3
- the response after convolving the measurement with an inverse logsweep
Measurement sequence
- the Parallella generates the logsweep signal and simultaneously outputs it to spdif and extracts the spdif measurement data from the microphone
- data is saved to SD then analyzed: determine the logsweep start from the sinewave header, do the convolution and save the impulse response to SD