How to process audio?

I was thinking about the SoundPuddle ( project was posted in the OffTopic forum. The LEDs have already been demonstrated by devhammer and ransomhall.

The audio aspect I first thought could be handled by the MusicModule, but on second thought a Ogg Vorbis recording stream doesn’t seems to be the “right” way of doing in it. It’s compressed and the audio data is in containers, rather than just a raw stream.

I’ve had other projects mind that would do basic audio processing - low sample rates due to the relatively limited processing speed of FEZes. For example it would be neat to make a very basic graphic analyzer - maybe 4 frequencies only.

So I am looking for some help on this - any suggestions on boards/modules/chips that would take a mic or line-in signal and produce info about the sound being captured?

Take a look at Parallax Propeller:


On that page there’s a project and he said he’s using a MCP3208 to the ADC.

A google search lead to this: Arduino Playground - MCP3208

On that page it has this:


1-8 - chan 0-7 -> the 8 levels to be measured
10 CS chip select -> D10
11 Din MOSI -> D11
12 Dout MISO -> D12
13 CLC clock -> D13
14 AGN -> GND
15 Vref -> reference voltage (that gives max adc reading)
16 Vdd -> supply voltage, max 5.5V so Arduino 5V is fine 

Would one just connect the microphone input into pin 1? (the + of the input, I guess the gnd would go to ground???)

FWIW - This seems helpful :

Here’s a microphone to use?

So I guess the Propeller would accept the audio signal and output the values via serial output.

I located another chip for the task on Sparkfun: MSGEQ7

This: lead to this: Christmasqualizer Is The Next Light Switch Rave | Hackaday

That lead to this: MSGEQ7 by J Skoba » NueWire . It’s an article about connecting that 7 channel EQ chip to an Arduino. The hackaday articles connects the Arduino to a couple different strands of xmas lights.

btw, there was a code snippet for rpl on the panda to do fast fourier transform(fft). That basically does spectrum analysis, for as many channels as you define, and have cpu time for.

Im mobile, so i cant search the forum to find the code.

It will probaly run a blast on Cerberus and family…

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Good point.

There are actually two submissions:

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Thanks for the info!