Can't say thank you enough for your willingness to share!
Was wondering how you approach guitar amp micing?
You mentioned you like using a combo of a 57, 421, 87 & 38
With the 57 & 421 placement do you have a go to starting placement? Or is it more generally listening for something sweet for each mic?
How much do you consider phase interactions when placing mics?
When tracking do you record a buss that is a blend of all your mics or do you track everything and blend in post?
Depending on how loud the amp is I'll place the 57, sometimes touching the grill, pointing right at the center of the speaker or just a little off axis. The more it's pointed at the center the brighter it is, and if the amp is loud enough, you'll get enough bottom. Taking it away from the center will add the appearance of more bottom. The 421 is placed off axis (on the same speaker) and pointing at the center. You'll need to experiment with the exact placement of that 421. Likewise with the C-38, you should experiment with it placed back about a foot. You can use the same speaker or try another. Most of the time I like to find the right balance between all the mics and print it on one track. Since it's all going to one track, if there is any phase concerns, you'll hear it. Sometimes the phase interactions can be desirable.