#4) Adonis Pro:
It qualifies for both FM/Am synth and is available as freeware. Here two individual voices can be synced and features 4 waveforms with fine pitch, tuning and level. The two multimode filters with 4 LFo’s varies in shape aliasing. The CV sequencer and modulation matrix of voices sets each one of them to separate levels. VST plugins for fl studio work well with the sine wave being actually quite refreshing. For free VST plugins download the plugin below.