..it seems to be so...
..almost at the first sight..
I've read on yampp3 website that there is a package which contains everythink you need to build yampp3/usb yourself,
it costs about 140? (without screen, keyboard hard disk etc.), plus hard disk and emulator...
With about 200? I can buy a great mp3 car stereo...
...but probably the package is too much expensive than the singles pieces...
I'm going right now to the shop to know how much  do they cost...
I've got no idea 
I hope less than I read... because I wanna try to make it!! 
Thanks for advices.

...another thing...
can Vitat's emulator be interfaced with other mp3 player different from yampp3?
or it's exclusively designed for yampp3?
...because the price of yampp3 seems to be bigger than a new car stereo with mp3 player capability!
..even if I like the idea of building something by myself...

Hi,
does anybody know how much does it cost
to make a yampp3/usb (components, etc. etc...) by yourself?

Hi Spumanti,
thanks a lot for the explanation.

I'm going to work on it right now!!

Bye, Dalailama.

Hi Vitat,
you're my only hope.
Can you tell me where I can find the circuit of the emulator, the list of components to do it,
and (if it is possible) how to interface it to IDE hard disk?
Another thing... are there any firmwares already done to program the device?
Thanks, Dalailama.

Hi, I'm a newby.
First of all I'm sorry if my english is not so correct.
I'm very interested of the circuit which emulate cd changer over ip-bus.
I want to make an Mp3 player which stores songs on an hard disk and to be able to control it by my pioneer DEH-P7300R HU.
I know it is possible because I saw somebody have done it yet, but I've get lost too many times during the search of what I have to buy, which is the circuit and how to make it work.
Could you help me?