Help with first DIY Amp Objective 2

[sofaspud]

Looking at the schematic, resistors R1 & R2 bypass the diodes D2 & D6 and limit the recharge current to the batteries to a reasonable level.
Regarding your OP, you ought to use a sacrificial pair of headphones when testing. IOW, something like those $1.50 types commonly offered.
You can use regular 9V batteries in the O2 for test and play, but do not leave them connected if the AC adapter is also used.
With soldering, it's important to know the difference between a good joint and a bad one. Then set about making good ones. Redo the ones that are bad. My position is that unless a person has some mental or physical handicap, it well within anyone's capabilities. Even with a <$10 iron.
I'll note also... the front leg of the S2 gain switch can short to the nearby via (beside R21). I used small wire cutters (not flush cutters!) and it was easily removed, no problem. Also, take care soldering the J2 input jack - the pin closest to the edge needs to be trimmed short and minimal solder used. These things are in the official docs but bear repeating.

[jschristian44]

I don't remember reading any of that, thank you. I know about the piece of jumper wire that I should hard wire to the case to create a solid ground rather than a virtual one, but i never heard of the things you just said. Can you point me towards them?

[sofaspud]

At least some of those things have been discussed here in the forum's main O2 thread. I think they have all been incorporated into the O2 Details page. Look for the Construction Tips section near the top, where NwAvGuy has several bullets addressing various issues.