From my brief experience with "converters" and their software...they all want to record and convert to mp3, which is shit quality compared to wav...when you got the levels up and the music is pumpin, it's the difference between audio tape and vinyl, so I used to record into wavepad/audacity and choose to record as a wav file for its lossless quality. My Numark USB deck wouldn't work without itunes being installed and would only save in mp3 unless I routed it through other software...you may find you get a nicer copy from cassette to PC if you just use the analogue audio input...although it's also fair to say here that the small stereo jack plug is a shitter compared to phono/line ins.
I use an old Technics tape deck, there is a certain, but small, amount of adjustment that can be made to the head by tightening or slackening the screws that hold it on, this helps with finding the optimum position to read/record old tapes that have gone baggy/slack or may have been recorded on a million times....obv this is propper Heath Robinson but seems to work.
