Sennheiser
MD 421-II
Dynamic · Cardioid · 30–17,000 Hz · a rider regular
- The five-position bass roll-off wheel runs M to S — music to speech — and the setting between them is the one nobody agrees on.
- The MD 421 has been in production in essentially the same shape since 1960; the MD 421-II is the current version of it.
Frequency response
Redrawn from Sennheiser’s published response graph (approximate, ±2 dB) on the fixed MicSense scale — 20 Hz–20 kHz, −20 to +15 dB — so two microphones can be compared at a glance. No image is copied; it is a guide to the shape, not a measurement. Drawn for: bass control "M" (solid curve); the dotted bass-cut positions are not used. The maker’s graph (FREQUENCY RESPONSE graph, product specification p.2 (dBV, normalised to 0 dB at 1 kHz)).
Polar pattern
Generated from the first-order directivity formula for cardioid. It illustrates the pattern type — it is not a measurement of this individual model.
Specifications
| Manufacturer | Sennheiser |
|---|---|
| Model | MD 421-II |
| Type | Dynamic |
| Form factor | End-address |
| Polar pattern | Cardioid |
| Frequency range | 30–17,000 Hz |
| Sensitivity | 2 mV/Pa · ≈ -54.0 dBV/Pa |
| Max SPL | — not published by the maker |
| Self-noise | — none (passive capsule) |
| Impedance | 250 Ω (electrical impedance) |
| Connector | XLR3M |
| Powering | None (dynamic) |
| Weight | 385 g |
Specifications: Sennheiser specifications page · last checked 2 Oct 2026. These are the maker’s published figures for this model. A dash never means zero: “not published by the maker” means the maker’s documents give no figure; “not yet checked” means MicSense has not confirmed one yet. Spotted an error? Tell us.
MicSense notes
| Price tier | Pro |
|---|---|
| Introduced | — not recorded |
Price tier and “a rider regular” are MicSense’s own judgement, not the maker’s.
What it gets used for
- Toms
- Guitar cab
- Horn / brass
- Bass cab
- Broadcast
MicSense tags microphones by the job on a live stage, not by studio category — so you can filter for “kick in” or “monitor vocal” instead of working backwards from “large-diaphragm condenser”.
MD 421-II alternatives: closest in published specs
Based on published specifications only — always listen at soundcheck. These are the microphones in the MicSense library whose datasheet figures sit closest to the Sennheiser MD 421-II’s for the same live job, with the reasons. It says nothing about how they sound.
Not compared for the Sennheiser MD 421-II: max SPL not published by the maker.
-
Shure
SM57
- Same job: toms, guitar cab, horn / brass
- Same type: dynamic
- Same cardioid pattern
- Same form: end-address
- Similar published response shape (≈ 1.5 dB apart on average, 100 Hz–10 kHz)
- About the same output — within the datasheets’ tolerance
-
Audix
i5
- Same job: toms, guitar cab, horn / brass
- Same type: dynamic
- Same cardioid pattern
- Same form: end-address
- Similar published response shape (≈ 1.7 dB apart on average, 100 Hz–10 kHz)
- About the same output — within the datasheets’ tolerance
-
sE Electronics
V7 X
- Same job: toms, guitar cab, horn / brass
- Same type: dynamic
- Same form: end-address
- Similar published response shape (≈ 1.2 dB apart on average, 100 Hz–10 kHz)
- About the same output — within the datasheets’ tolerance
- Supercardioid instead of cardioid — deepest rejection at ±126°, not 180°: check where the wedge sits
Compare it against the alternatives.
MicSense lets you put up to four microphones side by side — spec table, overlaid response curves and polar diagrams on one screen. Free with a free Squaresmile account.