Did anyone DIY Headroom electronic module by yourself before? I believe I am the first one and the only one did this. This is one of my little project as SUPER HEADROOM FAN at least one year ago.
Before upgrade, stock '04 Premium Module.
After I upgraded it to '05 Max module level , the changes are all 0.1% tolerance Vishay Dale metal Thin film resistors throughout the circuit board, deep and full(including output buffer stage) class A biasing as '05 Max module, best tiny caps for power rail decoupling.........
The only thing I can change at any time but not change is the 2134s. I still haven't upgrade them to OPA627 yet but I think it is not cost effective to me any way as it does not have dimond buffer as '06 MAX does.
Side Note: This is not the picture of the final module board, I did not even clean up the module board yet. I am lazy, I don't want to open up my MOH again.
To me this upgrade is for fun. Some challenges at implementation stage are soldering temperature control when dealing with certain type of caps, also developed my own procedure for desoldering whole module board off from the main AMP board......