converting midi tracks to audio tracks

Hi all,
If this has been answered a million times, please just point me in the right direction to read the answer. I’ve got a Roland synth that I’ve got midi’d through a Tascam US-600 interface to my laptop. I bought the Tascam and got Cubase LE5 as the sequencer software. I’ve successfully completed a midi composition (I added one audio track of guitar) and now I’d like to say presto and have the whole project export to a wav or mp3. Simple huh? As you might guess, my exported wav only includes my guitar audio track and none of the midi audio. Cubase support referred me to Tascam, since it’s OEM software and omg the video that Tascam referred me to on youtube made me want to claw my eyeballs out trying to understand wtf it was talking about. Surely…SURELY this is not a difficult process. Can someone please walk me through this, or like I said if it is already posted a million times just refer me to the answer? Thanks in advance. Btw - the documentation was a joke and does not cover this at all.

Export it by itself first.

I guess you are using a small mixer to combine the sound from cubase and your synth?

Record the synth/ midiparts back into cubase AS AUDIO, so record the L/R audio output of your keyboard back into cubase as stereo audiofile. So connect the keyboard L/R out to your soundcard stereo in, create a stereo audiotrack, assign the keyboard output to it and record the sound. Now if you playback or bounce keyboard audio + guitar track (mute the midi, you don’t need it anymore) from cubase you will get a full mix.

You can record all midi at once, just record the L/R output of the keyboard. You could use this as a " reference mix" to any experiments with separated outputs:

You could record part by part ( just solo a miditrack) and end up with multiple audiotracks, to process the separate sounds further in cubase…If you record sounds dry for example, without effects from the keyboard, you can use better sounding effects from cubase instead of those of the keyboard. You can also use level/eq/panning on every part much easier this way, in the cubase mixer. Just make shure all the midi sounds you want to process separate are recorded as multiple audiotracks.