I would not push the levels on the JB3 EVER. What you will notice, even at say, +4dB line-in boost, is some beeping periodically in the recording. It is not too pronounced, but it is there. If you get a good signal, get a preamp, that is the only way to do it unless you boost post recording. But even then, if the signal is tooo weak, you have problems boosting to listenable levels without it sounding like ass.