You need to attach some cable to reroute the sound back to your computer or attach speakers.
The usb/midi cable only transfers data to the device.

Okay, and what cable do i need? 😀

(I'm really bad with hardware)

And i thought i had all the cables i need 🙁

Probably something similar to this:

http://www.sweetwater.com/store/detail/IPMB2Q5/

Although I'd swear cables similar to those were much cheaper back when I was looking for them a few years ago!

@Deemster

FYI, the MIDI cable is meant to send and receive MIDI commands (which are only a few bytes), not to transport the audio output.

Thanks a lot for the answers guys!

I bought the right cable to connect my MT-32 into my microphone jack (Since my computers don't have a line-in jack) and it sounds fantastic! Even General Midi files (after sending mtgm.mid to the device of course) sound great 😀

By the way, is it true the UM-ONE usb-to-midi cable doesn't work on Linux? Because i use the latest Ubuntu on my laptop, and i would love to attach my MT-32 to my laptop too when i happen to be upstairs.

According to this http://alsa.opensrc.org/USBMidiDevices it should...but...the fastest way is to test it yourself...

Yeah bloodbat, you're right 😀 It's just, i have googled if the cable works on Linux and i found a few posts from people saying it didn't work. But i will try it tomorrow! I just worried since the disc that i got with my Roland UM-ONE cable only came with Windows and Mac drivers.. But i will see tomorrow if it works, and if not, then i will probably have to buy another cable. Anyways, i'm really excited to finally have a working MT-32! Munt is an awesome project, but it still doesn't sound quite te same..Especially the reverb. Plus you cannot send external sysex files to munt, especially THAT bothered me. Well thanks for all your advices, i now understand all i need to know. (I can still slap myself in the face, that i just assumed my MIDI CABLE would send audio back to my speakers :') )

"you cannot send external sysex files to munt"

What do you mean? I have several MIDs with separate sysex files, and they work perfectly.

+1
And, actually by now, the reverb _was_ inaccurate 😀 😀 😀 I eventually managed to recreate the exact model, it is in the final stage...
Btw, I think the most annoying thing should be unavailability of ROMs, but it seems this doesn't matter after all 😉

Hmm, then i guess i accidently had an older build of munt on my laptop ;o One final question about Munt though..

Some games exploit bugs on the first-gen MT-32. Does Munt play these tunes correctly as long as you have first-gen roms?
Or does it depend on other things than the roms?

Btw. Don't get me wrong, i have deep respect for Munt and it's creators. Creating such an accurate emulator without ANY support from Roland is the greatest emulation achievement ever done in my opinion. I'm just very nitpicky about the sound 😀

Well, there're several #ifdef's intended to reproduce the bugs in the old control ROM, not carefully tested so far. The problem with those bugs is we have now no access to an old MT-32. But the hope is to finish those soon. This is my priority #1 now after the reverb is completed.