I read somewhere that the single diaphragm LDC tend to be a bit more useful for 'distant' recording, such as a choir, and the dual diaphragm have better off-axis response for closer work. I've been doing a huge amount of reading these days, so can't remember where I saw it.
Keeping that in mind, a 2nd
AT4040 sounds good to have, just for a pair. Harvey Gerst pointed out the opposing view for using LDC as overheads, as they are less accurate, and impose a different sound on the kit. YMMV depending on if that sound is desired or not desired.
I have a set of C4 for my overheads, and absolutely nothing in recording mileage compared to Harvey. For me, "safe" techniques will produce decent results as I build experience. My
AT4040 was intended for voice, and is now complemented by an MXL V67M that I got from an HR member a few days ago.
I looked at the NT5, and really like their robust, physical build quality. Compared to the C4, the NT5 are single capsule, and tend to be more dark in the high end. I found the C4 to be a better value, overall.
The MXL603 review well, and appear to be a good choice for the absolute, rock bottom price range.
