hsc3-0.17: Help/UGen/sum4.help.lhs

    > Sound.SC3.UGen.Help.viewSC3Help "Sum4"
    > Sound.SC3.UGen.DB.ugenSummary "Sum4"

> import Sound.SC3 {- hsc3 -}

> g_01 = sum4 (sinOsc AR 440 0) (sinOsc AR 441 0) (sinOsc AR 442 0) (sinOsc AR 443 0) * 0.1

> g_02 = mix (sinOsc AR (mce [440 .. 443]) 0) * 0.1