Here's a few terms I use frequently. I'll add more and organize this over time. This glossary in in response to a post I made at HomeRecording.com in an MXL 990 thread...

Headbasket - The shaped wire mesh and frame that surrounds the capsule. Provides AC hum, Radio Frequency Interference (RFI) shielding and some protection from environmental contamination. There is a direct correlation between shielding efficacy and acoustical transparency. Less wire mesh equals greater open area percentage, less internal reflection and thus faster transient response settling time and a "more-open", less colored sound. 

Headbasket shape - There is a correlation between headbasket shape and internal reflection amplitude, settling time and distribution of standing waves vs. frequency. A cylindrical / flat-top headbasket as used in the MXL 990 has more accumulation of internal standing wave coloration than the classic, angled M 49 / U 67 / U 87 shape pioneered by Neumann to reduce headbasket coloration effects.

"Popular SDC Capsule" - I use this term as a catch-all to describe the capsule found in the 990, 770, MCA-SP1, Nady SCM-800 and a host of "MXL 693-like" pencil mics. Outside diameter is about 22mm with an 18mm diameter diaphragm.

Capsule Diaphragm Set-Back - These popular SDC capsules are designed in a such a way that the diaphragm is located some distance away from the front edge of the capsule housing. This "set back" creates a resonant chamber in front of the diaphragm that imparts coloration to the sound pick up. In addition the setback creates some acoustic shadowing and imparts some unevenness to the off-axis response. By contrast, mics like the Neumann KM 184 have the capsule diaphragm located much closer to the front edge of the capsule housing to reduce set-back coloration to a minimum.

Capsule Diaphragm Resonant Tuning - A condenser capsule diaphragm is a piece of thin material (most often Mylar) wth a thin layer of gold applied to create one plate of the "condenser" (capacitor). The gold-coated material is stretched over a mounting ring (usually round, but there are other shapes) and pulled up to the desired resonant frequency (like a drum head) and secured in place.

K67 capsule - Neumann's "second generation" LDC capsule. Designed with an intentional, narrow-band HF peak. Functions as the first stage of a pre-emphasis / de-emphasis system in the U 67 and U 87 mics. This topology offers increased headroom, sibilance reduction and a degree of control over frequency response. The K 67’s peak HF response is centered in the sibilance range then fedback inversely to provide an anti-sibilance response in the U 67 and U 87 mics.

The K67 capsule requires the proper HF attenuation to restore proper timbre-balance and not sound excessively bright or sibilant. It is this second stage “anti sibilance” feedback network that is missing in most low-cost K 67-type capsule mics that use a simpler “flat response” circuit.

Flat Response Circuit – The circuit that follows the capsule which provides high-to-low impedance conversion of the capsule’s signal and line-driving capability. The most frequently seen type of circuit in low cost mics is a close approximation of a flat response, transformerless topology pioneered in Schoeps microphones. This circuit was adopted primarily to avoid the cost associated with a high quality output transformer. Unfortunately, the flat frequency response of this highly regarded circuit (clever design, fine sound, excellent transient response) is not the correct match for the HF peaked response of the K 67-type capsule which is often found ahead of the circuit.

K47 Capsule – Neumann’s first generation LDC capsule found in the U 47 and M49 mics. No HF peak, but rather a gentle and broad “presence mound” in the upper midrange. Achieves proper timbre balance with a flat response circuit as used in the U 47.

Ceramic Capacitor – an extremely low cost capacitor frequently seen in the critical capsule-to-FET (or tube) location that provides coupling of the capsule’s audio signal into the FET gate (or tube grid) while blocking the diaphragm polarization voltage from reaching same. Unfortunately, this capacitor type – used in this location, handles the entire low level capsule signal and imparts an edgy, grainy or harsh sound to the audio. Higher quality mics use capacitors with better electrical parameters and thus better sound (Mylar, Polypropylene, Polystyrene, Silver Mica).

Electrolytic Capacitor – often used to provide relatively large capacitance in a small size to pass low frequency audio and block DC. These can introduce cross-over distortion again heard as harshness, edginess or lack of detail.

more to come...