Guitar Hero: Warriors of Rock

You need to be in Quickplay+ for this achievement. A standard band is a band with no duplicate instruments, e.g. you can't have two guitars. I presume it can be done on "Bleed it out" by Linkin Park with an expert guitarist and expert bassist. On "Bleed it out", for the two gold medals in a standard band you need to hit 1,070+ notes and score 170,000+. You should do this achievement early in the game because you will need a song that has no medals earned on the band challenge. It can be done however on any difficulty.

To do this solo you'll need a guitar and mic/headset. Put the mic on expert and the guitar on medium or higher. Medium is the minimum at which this will work and you'll need to hit every star phrase there is. Using the "fan method" on the mic play No Sleep Til Brooklyn from GHWT import. Hit every star phrase and hold until after the second or third flaming phrases which will give x3 for the band. When a spot opens up for you to hit the button for star power on the mic controller do it and immediately follow up with the guitar star power. There should be enough to get gold for the Bandx5 challenge if you've hit all the phrases and kept them banked. The score challenge will be no problem either.

If you have already unlocked 2/3 the band challenges than a useful workaround (without moving your save file) is to load up the game using another account (silver works) and play the guitar on your main account as the second player. This lets you acquire the 2 golds all over again.