Korg monotron DUO Reviews
This is an astounding and inspiring little device, which easily facilitates analog modulation between two independent VCOs along with a filter. Us (very much) older synth-heads would have been in heavenly bliss to even imagine owning such a thing -- in a palm-sized package. There is nothing better than learning the characteristics of analog sound and the principles of modulation than an analog synth.
I have given this one to my 10-year-old nephew who is just exploring music and its appreciation. He (and his dad) could not put it down for hours.
Portable True-analog Ribbon Synthesizer with Dual Oscillators, Cross Modulation, Classic Analog Filter, Internal Speaker, Aux Input, and Headphone Jack