Buying a pair of external mics is highly recommended. Depending which external mics you choose you’ll take one of two general routes.
External mics that can be powered by phantom power (I.e. power provided by a recorder or preamp through XLR cables that’s in the 24/48 V range). This is the case for most (all?) full bodied mics as well as setups where the microphone capsule is separated from the body/preamp (known as an “active setup”). The latter is preferred by many here, but the kit needed for this is definitely not cheap. In terms of the recorders you mentioned, the DR-40 can provide phantom power through its XLR jacks while the R-07 cannot. If you were to run mics requiring phantom power you would need an external pre amp capable of providing phantom power if you wanted to use the R-07. Keep in mind that providing phantom power can quickly drain batteries, so you’ll also have to consider providing adequate power to the recorder or preamp itself.
Other mics (such as the Church Audio series) are smaller and require less voltage. These mics can be run on what is called “plug in power” which is somewhere in the 5V range. This level of power can be provided by the R-07, but it is highly recommended to use an external preamp or battery box as while the voltage most recorders provide can power the mics enough for them to function, they don’t provide enough power for the mics to function to their maximum potential. Specifically, at the power most recorders provide microphones will become overloaded at higher SPLs leading to audible distortion.
Given that you’re looking to go with a smaller profile rig, I suggest looking at the mics made by Church Audio or the AT-853s. Church audio always makes a few different battery boxes/preamps that you might consider. If you have a significant amount of money available to spend, you’ll be served well going with an active setup. If you choose to go the active route, make sure to do a lot of reading about the gear needed to do so.
I also recommend listening to as many tapes as you can find of different types of mics before making a purchase.
Hope this answered some questions you may have and that it also raised new ones. Taping is a technical hobby, but that makes it all the more rewarding. There’s some excellent information on all of this (and more) on the forums. Poke around a bit and you’ll find a lot of useful info. The crew here are a generally helpful and accepting bunch, so don’t hesitate to ask questions.
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