Shure
Shure SM137
Small-diaphragm cardioid electret condenser (end-address probe) for instruments, with a 15 dB pad
Approximate Some readings for this mic are uncertain; see the graphs.
Power Phantom 48 V DC.
- Type
- Condenser (electret)
- Pattern
- Cardioid
- Sensitivity
- −41 dBV/Pa
- Among 204 condensers: more output than 29%
- Among 311 mics: more output than 50%
- Self-noise
- 19 dB(A)
- Among 258 condensers: quieter than 29%
- Among 272 mics: quieter than 28%
- Max SPL
- 139 dB SPL
- Among 277 condensers: takes louder sound than 58%
- Among 343 mics: takes louder sound than 53%
- Rated range
- 20 – 20k Hz
- Released
- 2009
vs 75 end-address condensers
More output than 15% of 75 end-address condensers.
Each stripe is one end-address condenser with a published sensitivity, and each bar counts them; further right means more output. This mic is in blue.
vs 104 end-address condensers
Quieter than 27% 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 59% 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.
Instruments sources recommend it for most
5 of 7; all under Recommended for.
Proximity effect: the bass it gains up close
From the spec sheet, p. 11.
"Frequency Response"; relative dB. Distance, room and smoothing not stated (the user guide calls it "typical").
Dashed: outside the rated range, or simulated (other angles and distances). Hover or tap the graphs for values.
Polar pattern
From the spec sheet, p. 11. Approximate
"Polar Pattern, Measured at 1000 Hz" (as printed, though it shows six frequencies); two plots, 250 Hz to 1 kHz and 2400 Hz to 10 kHz; 0° at the bottom, 5 dB per ring from +5 dB (outer) to -20 dB. Measuring conditions not stated.
Approximate: reading error up to about 1 dB; some frequencies are identified by reasoning, not by the legend: 500 Hz, 1k Hz, 10k Hz.
In practice
All specs
| From the spec sheet | ||
|---|---|---|
| Capsule | 2.5 µm, 24-karat gold-layered Mylar diaphragm | p. 11 |
| Sensitivity | −41 dBV/Paopen circuit voltage, 1 kHz | |
| Self-noise | 19 dB(A)typical, equivalent SPL, A-weighted | |
| Max SPL | 139 dB SPL1 kHz, < 1% THD, 1000 ohm load; also 144 dB SPL, 2500 ohm load; also 154 dB SPL, 1000 ohm load, pad on; also 159 dB SPL, 2500 ohm load, pad on | |
| Signal-to-noise ratio | 75 dBreferenced at 94 dB SPL at 1 kHz. "S/N ratio is difference between 94 dB SPL and equivalent SPL of self noise, A-weighted". | |
| Dynamic range | 122 dB1 kHz, 1000 ohm load; also 128 dB, 2500 ohm load. The user guide (p. 4) prints the 2500 ohm figure as "128 dBV". | |
| Output impedance | 150 ohmactual | |
| Rated frequency range | 20 Hz to 20 kHz | |
| Powering | phantom 48 V DCUser guide (p. 3): performs best at 48 V "(IEC-268-15/DIN 45 596)" and works down to 11 V with slightly less headroom and sensitivity. | |
| Current draw | 5.2 mA | |
| Pad | −15 dB"Attenuator: −15 dB"; two positions, 0 and -15 dB. | |
| Connector | XLR-3 male"Three-pin professional audio (XLR), male". | |
| Weight | 195 g | |
| Dimensions | 24 × 162 mm"162 mm L x 24 mm" (diameter × length). | |
| Supplied accessories | swivel adapter; zippered pouch"Includes a swivel adapter and a zippered pouch". The 2009 user guide (p. 4) lists a 95C2313 storage bag, an A3WS windscreen and the A25D swivel stand adapter; the sheet lists the A25D as an optional microphone clip. | |
| Clipping level | 3 dBV into 1000 ohm, 9 dBV into 2500 ohm (20 Hz-20 kHz, 1% THD) | |
| Common mode rejection | > 50 dB, 20 Hz to 20 kHz | |
| Polarity | Positive pressure on the diaphragm gives positive voltage on pin 2 with respect to pin 3 | |
| Optional accessories | A55M, A55HM Shock Stopper isolation mounts; A53M isolation mount; A25D microphone clip | |
| From the user guide (Recording Hacks copy) | ||
| Rated load impedance | 1000 ohmrecommended minimum. "Shure recommends a minimum input load impedance of 1000 Ω". | p. 3 |
| Electronics | Class A, discrete, transformerless preamplifier; three-layer mesh grille as pop filter | |
| From the Recording Hacks page | ||
| Released | 2009 | |
Documents
- SM Wired Microphonesspec sheet for the SM range; SM137 on page 11
- SM137 Cardioid Condenser Microphone, User Guide27A12629 Rev. 1
- Shure SM137 | RecordingHacks.com
Copies kept by Mic Archive (manufacturers move and drop their documents). Each is © Shure, unchanged, with its original address.
Recommended for
By recording guides, engineers and mic makers, for this mic or an earlier version of it.