Blend sound effects and recorded sounds together?

Projects General Guidance
1

Hi,

I have looked through many tutorials, but I am just not getting this figured out. All of this talk of synthesizers, voices, midi, tones, sampling, etc. has left me confused.

I need to be able to do two basic things: 1) Generate sounds like beeps, swooshes, crashes, hum, i.e. sounds from science fiction machines. 2) Play a recorded human voice from an SD card, for example "self destruct sequence activated."

Can anyone explain to me the basic approach to use Arduino to do both of these things on the same speaker? I assume that I can use Arduino software and existing Arduino output pins to do #1, and I have an SD shield for #2, but I don't have specific instructions to accomplish either of them. Can I take the output from two digital output pins and send them into an amplifier to blend the two sound sources together? Does it work like that?

Please help me and other forum users by describing the overall process, then point me to some short software examples to do this stuff. I keep finding info on synthesizers, but I am not trying to play music or reproduce musical instruments.

2

Creating a sound other than a PWM output requires processing to be occurring.
Reading from SD cards requires processing to be occurring.
Arduino's are only capable of processing 1 thing at a time.

What you can do is control playback of sounds from a "sound shield"
http://www.mdfly.com/index.php?main_page=advanced_search_result&search_in_description=1&zenid=42dad9120d382ce716cc25db9b836b44&keyword=mp3&x=-310&y=-103

and mix that in the analog domain (basically, 2 resistors) and amplify from there. Here you can see 8 outputs going thru 1uF caps, then a resistor, thru a potentiometer, out to a amplified computer speaker.

So fire off the command to have external card play a voice/whatever the SD card, and have the arduino make your whooshes, beeps, whatever.

PianoTest.JPG
PianoTest.JPG1209×558 137 KB

3

Thanks. I ordered a GinSing shield, which gives me all sorts of knobs and buttons for making special effect noises in a windows software tool, and then gives me the code that I need to place in my Arduino sketch to make that same noise in the embedded tool. The GinSing shield does all the processing so that I can do other stuff with Arduino. I don't know if it will blend playback sounds from an SD card yet, but it will at least do synthesized voice.