Phase alignment

Starting two oscillators how can I sync them to start at the same time one on each channel?

More info?

I'm not sure where your difficulty is. If you have two oscillator opcodes in the same instrument, they should automatically start in sync. If I'm misunderstanding. please explain further.

One oscillator per stereo channel

Like Pete G., I am not sure I understand what you are asking, but here is an example of what I think you want :

instr 1 ; stereo two oscillators
isine ftgen 0,0,512,10,1
aLeft oscil 5000,440,isine
aRight oscil 5000,660,isine
outs aLeft,aRight
endin