I contacted Tom at Tascam yesterday about the op amp chips and here is his response:
"You are looking at the wrong side of the PCB. The 4 mic pres use NE5532 op amps. The output stage and the 1/8" input for Channels 1/2 use the 4580s."
Well don't I feel like a buffoon.
I will tear into the deck again today most likely and check this out and post more pics if needed. Based on this new information it would appear that the JWmod will require 7 chips instead of just the 3 originally noted. I am waiting for a response from Jim currently and have been in contact with him regularly talking about this mod so hopefully I hear something back from him today.
So does any of the JW's commentary/mod have anything to do with the mic input stage...or relevant to the quality of the NE5532? Doesn't sound like it.
Makes me wonder about the whole thing. Modding something he doesn't have a complete understanding of...?
His posts make it sound like he thinks the chips he swapped have something to do with the mic inputs - which apparently they don't.(if Im following this correctly)
And he does call it "misinformation from Tascam" - also misleading...and ironic.