I have noticed that the market offers many more low budget (less than 300 bucks) audio USB interfaces than microphone preamps.
Some of them may work as a standalone mic pre, having often balanced or unbalanced line outputs.
Could it be possible to power them with an external battery pack via USB or in the AC plug?
Do you think that using one of these devices as a pre to upgrade the quality of a pocket recorder (like Edirol R09HR and others) can be a good idea?
Any suggestion of a particular device working better than others in the price range?
Thank you
c