I have tried all of the soft general midi synths recommended here and have to say that the Roland TTS-1 sounds the best on all of my hardware. That being said you can now compliment that sound with other sound modules both soft and hard. I got ez drummer and liked it so much I moved up to Superior Drummer to replace the drums. In my opinion better than real drums. I also have built up a collection of soft synths and sound modules. The vintage organs gives me a b-3 that's a heck of a lot lighter than the original and capable of being played just like the real thing. I also have picked up the legacy series of synths from korg. This gives me access to an M1, wavestation, poly 61 etc. I find I don't use these as much with BIAB but after transfering the BIAB file to a regular daw (You have a free one with Real Band) you find it a lot easier to add these to your arrangement and the sounds are not just good but excellent to fantastic. One of my favorite soft synths is an older copy of FM7 which is exactly like a Yamama DX7. The FM8 is the same but with more features.

Yes, BIAB doesn't sound good with the 5 cent sound card in your laptop. But with the soft synths that are out there it can really be made to sound great.

Dell 610 dual Monitor, win 7-10, Sonar Plat, ProTools 10 & 11, Reaper 4, BIAB/real Band 2022, Easy Drummer, Superior Drummer, Kontact Essentials, Personnel Orchestra, Korg Legacy Analog & Digital