AKG
AKG D 20 B
Dynamic, cardioid, studio and broadcast mic from the D 12 line, with a three-position bass attenuation switch and built-in steel suspension; discontinued
Approximate Some readings for this mic are uncertain; see the graphs.
Power None (passive). Low output: it needs a lot of preamp gain.
- Type
- Dynamic
- Pattern
- Cardioid
- Sensitivity
- −55.9 dBV/Pa computed
- Max SPL
- 128 dB SPL
- Among 343 mics: takes louder sound than 13%
- Rated range
- 30 – 16k Hz
vs 36 dynamics
Takes louder sound than 3% of 36 dynamics.
Each stripe is one dynamic with a published max SPL, and each bar counts them; further right means it takes louder sound. This mic is in blue.
Instruments sources recommend it for most
Proximity effect: the bass it gains up close
From the spec sheet, p. 1. Approximate
Data sheet p. 1, no title, distance or room stated; the solid upper line is taken as 0° and the dashed lower line as 180°, as on the labelled leaflet graph (p. 2). Relative dB.
Approximate: reading error up to about 1 dB.
Dashed: outside the rated range, or simulated (other angles and distances). Hover or tap the graphs for values.
In practice
All specs
| From the spec sheet | ||
|---|---|---|
| Technical data, D 20 B column (p. | ||
| Sensitivity | −55.9 dBV/Pa (1.6 mV/Pa)unloaded, 200 ohm version; also −60.9 dBV/Pa, 60 ohm version (D 20B/60), from 0.09 mV/µbar (leaflet, p. 2). Not stated by the manufacturer: Stated as "0.16 mV/µbar (-77 db re 1 v/dyne/cm²)"; converted: 0.16 mV/µbar = 1.6 mV/Pa, 20·log10(0.0016) = -55.9. The printed -77 dB does not match 0.16 mV (-75.9 dB); the leaflet (p. 2) gives "-76 dbv" for it. 1). | p. 1 |
| Max SPL | 128 dB SPL1% THD. "Max. Sound Level (for 1% thd): 500 µbar (128 db)". | p. 2 |
| Output impedance | 200 ohm±15%; 60 ohm version on order. "200 ohms, 60 ohms if specified"; the leaflet (p. 2) adds ±15% and the order numbers D 20B/200 and D 20B/60. 1). | p. 1 |
| Rated load impedance | 1000 ohmminimum, 200 ohm version; 300 ohm for the 60 ohm version. "Min. Actual Load Impedance for D 20B/60: ≥ 300 ohms; for D 20B/200: ≥ 1000 ohms". | p. 2 |
| Rated frequency range | 30 Hz to 16 kHz±2.5 dB related to the published curve; also [30, 18000], D 20 B leaflet (p. 2). "Frequency range: 30 ... 16 000 cps"; "Frequency response: ±2.5 db rel. to published curve". The leaflet reads "30...18 000 cps". 1). | p. 1 |
| Powering | none (passive)A dynamic mic; no supply is mentioned. | |
| Low cut | 0 dB, -7 dB, -12 dB; 50 Hz"Bass attenuation switch: 0, -7, -12 db at 50 cps"; p. 2: "Provides clear response at close talking". 1). | |
| Connector | AKG 3 S 17 B (pins 1-2 moving coil, 3 ground); the D 25 B has a fixed 5 m cable with free ends"AKG connector 3 S 17 B (supplied), 1-2 = moving coil, 3 = ground". 1). | |
| Weight | 730 gnet; also 630, leaflet, D 20B/60 (p. 2). "1 lb. 9.6 ozs. net (730 g)"; the leaflet gives "630 g" for the microphone. The D 25 B: 840 g. 1). | |
| Dimensions | 186 × 77 × 54 mm"7 5/16" x 3 1/16" x 2 1/8" (186 x 77 x 54 mm)", order not stated; the D 25 B 200 × 150 × 80 mm. 1). | |
| Supplied accessories | 3 S 17 B connector; SHZ 4 thread adapter (3/8", 1/2" and 5/8"-27); wooden case"The D 20 B is delivered in case, with 3 S 17 B connector"; stand connector "built-in thread adapter SHZ 4"; p. 2: "supplied in elegant wooden case". | |
| Front-to-back ratio | Better than 20 dB at 180° | |
| Noise voltage | 0.26 µV weighted (CCIF 1954 filter, DIN 45 405); 0.2 µV unweighted | p. 2 |
| Suspension | Built-in steel suspension (shock mount); the D 25 B has a rubber suspension in a swivel frame | p. 1 |
| Grille | Rugged wire mesh with built-in pop screen; the front (sensitive side) is marked by a light coloured grille | |
| Magnetic shielding | Effective magnetic shielding, for pickup at very low sound levels | p. 2 |
| Versions | D 20B/60 (60 ohm) and D 20B/200 (200 ohm); D 25 B for booms, same specifications except the cable | |
| Accessoriesoptional | Floor stands St 200 and St 101, St 102 boom, table stands St 301 and St 10, studio-matching transformers U 3027 and U 3053, MSH 30 flexible shaft | p. 1 |
Documents
- D 20 B / D 25 B Dynamic Cardioid Microphones (data sheet), with the D 20 B Dynamic Studio Microphone leaflet
- "All the World's a Stage..." - Sound by AKGcompany history booklet
Copies kept by Mic Archive (manufacturers move and drop their documents). Each is © AKG, unchanged, with its original address.
Recommended for
By recording guides, engineers and mic makers, for this mic or an earlier version of it.