Feasibility of mounting , reading and writing to an external drive (Octatrack)

Hi All. This is my first post so I apologize if I break any rules. I'll try to be succinct.
I have tried to search for this on google but given the topic and my inexperience, I'm not sure the correct phrases to be searching. Anyways,
I have an Octatrack (which is a music sampler), which uses a CF card as storage for audio samples. I am currently building and external MIDI controller (which I think I have a decent handle on at this point) but I thought it would be handy to also have the ability to pass wav files back and forth to the CF card on the Octatrack from an SD card on the controller. The Octatrack mounts itself as an external drive via USB on the PC much like a media card reader, without drivers, so I assume it's class compliant (if that is even applicable in this case). Before I start putting together Frankenstein's monster, I would like to know if anyone knows if it is feasible to use an Arduino to access the CF card through the Octatrack. I have UNOs, Megas, Pro minis and a Due kicking around. If you need further information, please let me know. Thanks so much!

Hi,
Hopefully someone with better knowledge of USB connected drives can help.

There is how-to and code for running an ATA type drive in the book JUNK BOX ARDUINO by Jim Strickland (Apress).

DISCLAIMER: I am a technical reviewer in the book.

Thank you Terry. I appreciate the response. I am in South Korea at the moment so getting books is a bit of a mission. Should it come to that, I'll see if I can order it. Thanks again

You can get USB connected Memstick/SD/CompactFlash readers/writers on Ebay for about $3USD. No Arduino required, just two USB ports on your PC.

CF works just like SD, only has different pin-outs.

I think my original post wasn't entirely clear. I'd like to move files back and forth between an SD card and a CF card without a pc involved. In other words, Id like to be able to mount the Octatrack (which acts as a CF reader/writer) via USB to an arduino which is also connected to an SD card. I just want to know if that is possible. I'm still poking around and finding tidbits here and there. Thanks for your reply though.

This would be a much more straightforward problem if you used a Raspberry Pi.

With an Arduino you can read/write SD cards easily enough but USB is a much more complicated problem. I don't think this would be practical without a USB Host Shield.

Well perhaps I could dig up a usb host shield. That would do the trick for now. Thanks for pointing that out!