With the SP-303, its cool how you can resample and record externally at the same time. I love the 404's features, but I'm frustrated you can't do this on it. So, I found a workaround.

If you have any recording device with its own mic (4-track, handheld digital recorder, etc), connect its output to the SP-404 mic input. Then keep your headphones plugged into the SP-404. With a sample/loop playing on the SP-404, you can listen to it and jam along on your keyboard or guitar (or whatever) feeding into your other device's mic or line input. WIth your headphones into the SP, you can hear everything at once, and if you want...preview how it will sound in the mix compressed or with effects. Whenever you are ready, hit record on the recording device and play whatever you want to play, all the time monitoring on the SP. THen, simply record your new recording into the SP. Instead of playing guessing games or recording loops out of the SP, since you jammed with the loop live, the recording will be right in time.

me no comprehendo but need to figure this out