Audix
Audix MB8450
MicroBoom system: the M1250B miniature cardioid condenser on an 84" (2134 mm) carbon-fibre boom with gooseneck and stand clutch, for choir, theatre and orchestra
Approximate Some readings for this mic are uncertain; see the graphs.
Power Phantom 18-52 V (48 V recommended).
- Type
- Condenser
- Pattern
- Cardioid
- Sensitivity
- −40 dBV/Pa computed
- Self-noise
- 21 dB(A)
- Among 258 condensers: quieter than 19%
- Among 272 mics: quieter than 19%
- Max SPL
- 140 dB SPL
- Among 277 condensers: takes louder sound than 62%
- Among 343 mics: takes louder sound than 56%
- Rated range
- 50 – 19k Hz
vs 104 end-address condensers
Quieter than 15% of 104 end-address condensers.
Each stripe is one end-address condenser with a published self-noise, and each bar counts them; further right means quieter. This mic is in blue.
vs 110 end-address condensers
Takes louder sound than 64% of 110 end-address condensers.
Each stripe is one end-address condenser with a published max SPL, and each bar counts them; further right means it takes louder sound. This mic is in blue.
Proximity effect: the bass it gains up close
From the m1250b spec sheet, p. 2.
Titled "Frequency response", the cardioid line (yellow) of four capsules; relative dB (axis labelled "dBm", +10 to -10). Distance, room and smoothing not stated.
Dashed: outside the rated range, or simulated (other angles and distances). Hover or tap the graphs for values.
Polar pattern
From the m1250b spec sheet, p. 2. Approximate
Titled "Polar patterns", the "Cardioid" plot of four; full circle, 0° at the right. Scale "dBSPL" from 0 at the outer circle to -36 at the centre. A small image (circle radius 88 px). Measuring conditions not stated.
Approximate: reading error up to about 1.5 dB; some frequencies are identified by reasoning, not by the legend: 250 Hz, 500 Hz, 1k Hz.
In practice
All specs
| From the m1250b spec sheet | ||
|---|---|---|
| Capsule | 12 mm gold-vapour diaphragm, threaded modular capsulePage 1: "12 mm gold vapor diaphragm"; the A&E spec: "a modular threaded capsule". | p. 1 |
| Sensitivity | −40 dBV/Pa (10 mV/Pa)1 kHz. Not stated by the manufacturer: Converted from "10 mV (C/HC), 11mV (O/S) / Pa @ 1k" (20·log10 0.010). | p. 2 |
| Self-noise | 21 dB(A)"Equivalent Noise Level 21 dB (A-weighted)". | |
| Max SPL | 140 dB SPL0.5% THD; stated as "≥140 dB". "Maximum SPL ≥140 dB"; the A&E spec: "a maximum SPL level of ≥140 dB with THD of 0.5%". | |
| Signal-to-noise ratio | 73 dB | |
| Dynamic range | 119 dB | |
| Output impedance | 150 ohmat 1 kHz. "150 ohms"; the A&E spec: "nominal output impedance shall be equal to 150 ohms at 1 kHz". | |
| Rated frequency range | 50 Hz to 19 kHz | |
| Powering | phantom 18-52 V (48 V recommended)"Power Requirements 18-52 V"; Operation: "will NOT operate without phantom power voltage (48 Volts recommended)". The product page: "18 – 52 V phantom power". | |
| Current draw | 6.1 mAat 48 V | |
| RF immunity | Immune to RF interference from mobile phones and GSM devices | p. 1 |
| Microphone | M1250B: machined brass, black finish, 16 g, 54 × 12 mm | p. 2 |
| UseAudix | Cardioid: area miking or group vocals at 2-3 feet; speech or single voice 8-10 inches; instruments 3-12 inches | |
| From the spec sheet | ||
| Connector | mini XLR-3 male at the foot of the boom; 7.6 m cable to XLR-3 male"Connections: mini-XLRm (bottom), mini-XLRf (top)"; the mic has a "3 pin mini-XLRm" (M1250B sheet). Cable CBLM25: "25' shielded mic cable with mini-XLRf - XLRm connectors". | p. 2 |
| Weight | 127 gNot stated for the system: boom 111 g ("Weight MicroBoom™84 111 g / 4 oz") plus the M1250B 16 g (its spec sheet, page 2). | |
| Dimensions | 2134 × 7.4 mmBoom length × rod diameter: "2134 mm / 84 in", "7.4 mm / .2 in". The M1250B is 54 mm long, 12 mm in diameter (its spec sheet). | |
| Finish | black (MB8450) or white (MB8450W) | p. 1 |
| Models | MB8450: black, M1250B cardioid. MB8450W: white. MB8450HC / MB8450WHC: M1250BHC hypercardioid. MB8455 (W, HC, WHC): M1255B high-output capsules. The same systems with 24" (MB2450...) and 50" (MB5050...) booms | |
| Boom | Carbon-fibre rod with flexible steel gooseneck; shielded cable inside; the mic plugs into a mini-XLR at the tip (push-button release) | p. 2 |
| Stand adapter | MCBOOM: thumbscrew and wing-nut adjustments for angle, rotation and position of the rod | |
| Warranty | The MicroBoom sheet says "1 year warranty" in its features and 3 years in its warranty text; the M1250B sheet says 3 years | p. 1 |
| From the product page | ||
| Supplied accessories | MCBOOM mic stand adapter (clutch); CBLM25 7.6 m (25 ft) cable; WS1218 windscreen"The MICROBOOM System comes with a carbon fiber boom (24″, 50″ or 84″), microphone (M1250B, M1250BHC, M1255B, or M1255BHC), clutch assembly, 25′ shielded cable and windscreen." The MicroBoom sheet lists MCBOOM as supplied and CBLM25 as optional (page 2). | p. 1 |
| Price | $739 (cardioid), $789 (hypercardioid), as listed on the product page on 2026-10-19 | |
Documents
- MicroBoom Carbon Fiber Boom Armsver 6, 04.18
- M1250B Miniature Condenser Microphonever 3.2 09-16
- MB8450 Miniaturized Condenser Microphone w/84" Carbon Fiber Boomaudixusa.com
Copies kept by Mic Archive (manufacturers move and drop their documents). Each is © Audix, unchanged, with its original address.
Recommended for
By recording guides, engineers and mic makers, for this mic or an earlier version of it.