mp3 through tx and rx?

is it possible to do it? and how would it be done? like to read an sd card through spi and sent through tx and rx to another arduino?

well... it's not decoded mp3, itll be more like just the file, and then i have a decoder that would do the rest of the work for me, would that be any easier?

ok, =) well thank you for clarifying =)

2) There is the practical limit of the speed of the serial communication which would limit you to rather low-rate MP3.

If he is doing communication between two microcontrollers, he can set UBRR to 0 on both microcontrollers, with a 16 MHz Arduino, this should be about 2 mega-bits per second. I bet the MP3 decoder will only run SPI at 2 MHz anyways. In the end, by doing this, the best possible bit-rate is halved in the best-case scenario.