Hey,
I have an RGBW Emerald, and found this to be pretty close to a Deep Purple; however, the color necessarily gets dimmer as you lower the settings on each channel:
R: 12
G: 0
B: 44
W: 0
I just use R: 10 and B: 44 for the pulsing effect.
Good Luck!
Thanks! I'll give it a shot.