The problem with doing this on the Arduino are:-1) you can not open more than one file on an SD card at any one time and there is not enough SRAM to buffer them.2) as mentioned lack of a D/A, you have to use an external one and you have to bit bang the SPI interface because the SD card is using the hardware SPI Pins.
Take a look at https://github.com/TMRh20/TMRpcm It demonstrates quite clearly that you can open, access, and read from multiple files on a single SD card and play them back simultaneously using only a 328 based board and no shield.
Using similar methods on a Teensy or a Due would extend the capabilities quite a bit as well.
Interesting. Have you got any example videos of two files playing at once? The Yoda speaking video was not too impressive and that was only one sample at a time.Using the PWM timers as a D/A output connected directly to a speaker with no filtering but the "natural" frequency response of the speaker is a bit of a hack.I suppose if you reduce your expectations of what constitutes "work" you can work wonders.
Arduino Uno sound playback using PWM technique - I quickly abandoned that idea because the sound quality was really bad.
In this thread, http://forum.arduino.cc/index.php?topic=276594.0reply #3and he only wanted speech.So it is not just me that thinks this.
We find some links ,but, we don't know whether them are what we find for.here's links :https://www.sparkfun.com/products/8894http://188.8.131.52/~ruggedci/html/flexible_midi_shield.htmlhttps://www.sparkfun.com/products/12000If you could give me better alternative, please help.