Finally finished wiring up my T2, at least enough to try it.
Initial impressions are its a keeper, but letting it burn in right now.
My build is not per the instructions, I tend to always deviate, and I have no idea if my version is better or worse since I didn't try the original BOM.
I didn't buy the BOM walwart, and have no plans to buy it, so I will never know how it compares.
I decided to try a different walwart from Jameco, slightly higher current. I wanted something else from Jameco so I could combine shipping them.
My walwart is also higher voltage so I added a RC filter stage right after the switch, to drop the voltage down a few volts.
Its a linear walwart, so its output voltage depends on your house voltage, and I've found linear walwarts always run high at my house.
I've done this type of power input filter before for class a amps, since they are constant power and current draw, you can calculate what value resistor you need fairly easily.
I also have a bunch of power resistors in my junk drawer, so was able to do this without having to order more parts.
If you don't have a lot of diy experience, I would recommend sticking with the standard bom, and then you don't have to mess around like I did.
EDIT: EDIT again:
Wanted to add that I didn't install the input cap at first, and amp was really distorting.
I checked DC on my inputs, and found something like 5VDC, so I added the input caps and all was fine after that.
I thought there was an issue, but I forgot the pot grounds the signal, so I'm not sure why I have a 5VDC offset, need to figure it out still.
Keep thinking of more stuff.
If you use the PWB for the back panel, which is really convenient, there is a flex issue. Its a long, kind of skinny board, so I find if flexes quite a bit when I install my RCA cables into the input jacks.
My RCA cables are difficult to mate, so this will contribute to the amount of flex. Right now, I don't have a cover on it, so I can hold the back while installing RCAs to limit flex.
I'm thinking about adding a bracket in the middle of the back, or maybe right next to the input RCAs. I'm not using the output RCA's, didn't even install them.
Pulling out the RCAs is fine because you can push against the back when to remove so it doesn't flex out. When you install, if the cover is on, then you can't keep the board from flexing in.
Or you can use the metal back and should be fine, but you have to drill the holes for the RCAs and power input jack.
Also, if you care, my T2 is using 340 mA's. This is 40 mA above what is consumed by the 150 mA bias current for both channels.
FYI, 5.1V (voltage set across the bias resistor) / 150 ma = 34 ohms
you have two 68 resistors in parallel to get the 34 ohms, but my resistor values were a little low, and this would add a mA or so to the bias current.
Rest of current is likely consumed by the other parts in the circuit.