Perhaps you are confused. The Twin Q is not an audio interface as the term is commonly used. It is a dual preamp or dual channel strip box.

An audio interface in it's simplest form, is a device with analog inputs & A/D converters that interfaces to a computer.

Indeed, as AudioGaff says, it isn't an Audio interface, however if you buy an inexpensive audio interface with S/PDIF IN, you can take the digial feed from the converters in the TWIN-Q and send it to the interface, that way you have WAY better pre's and better converters than the $200 dollar interface hooked up to your computer.

Signal-->TWIN-Q--(S/PDIF)-->Audio Interface--(USB)-->Computer

The twinQ and a basic audio interface will still put you under a grand. But remember, GET A DECENT MIC!

thanks for telling me , yes i thought it was an audio interface when i read about it on joemeek website. can you suggest me any audio interface with good mic preamps i don't want many inputs our outputs.

You'll have to pick the device that is most suited to your needs. Presonus makes some decent firewire devices at the entry level, so does m-audio (also being pro-tools compatible if thats important....). Small steps up would be the T.C. Electronic devices... However if you are using the Joe Meek you won't need to worry too much about the pres built into the interface....