Frequency (2 channel common ref.) or Coherence training (bipolar montage)?

[Guest guest]

Dear Listmates,

Can someone clear up for me which is the preferred training regimen at

locations F4 and C4: 2 active-channel (frequency training), A2 common

reference~ F4/A2/Cz(g)/C4/A2 window squash, with 12-15Hz in the window; or 1

Channel Bipolar montage~ F4/C4/A2 rewarding 12-15Hz?

Which is more effective to impact training-the Coherence training in the 1

Channel bipolar montage (with the understanding by training under a bipolar

montage you are either increasing or decreasing the 12-15 Hz amplitude but you

are increasing the coherence and communication between these sites) or the 2

Active-Channel Windowed squash focusing solely on increasing the 12-15Hz

bandwith at these locations?

Thanks!

Mike