A review of two new end-address small-diaphragm electret condenser microphones from Shure--the KSM141 and KSM137. The KSM141 provide two polar patterns (cardioid and omnidirectional), two attenuation pads (-15 dB or -25 dB), and two highpass filters (at 80 and 115 Hz). The KSM137 is identical, but provides only a fixed cardioid polar pattern.
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A review of two new end-address small-diaphragm electret condenser microphones from Shure--the KSM141 and KSM137. The KSM141 provide two polar patterns (cardioid and omnidirectional), two attenuation pads (-15 dB or -25 dB), and two highpass filters (at 80 and 115 Hz). The KSM137 is identical, but provides only a fixed cardioid polar pattern.

It has been a few years now since Shure debuted its KSM series of studio microphones. The KSM32 led the pack, followed by the KSM44 and KSM27. All three were side-address, large-diaphragm — or at least relatively large-diaphragm — condenser microphones. Now, with the introduction of the KSM141, KSM137, and KSM109, Shure has broadened the KSM range to include end-address, small-diaphragm condensers.

This review focuses on the KSM141 (see Fig. 1) but also applies to the KSM137. That's possible because the two microphones employ identical electronics and capsules, the difference being that the KSM141 offers switchable cardioid and omnidirectional polar patterns, whereas the KSM137 ($575) has a fixed cardioid pattern. The only sonic difference I could ascertain between the two models was in the resonant tone of their housings when tapped externally; in terms of cardioid sound capture, they sounded identical.


The KSM141 is an end-address, permanently polarized (“electret”) condenser microphone featuring a Class A, discrete, transformerless preamplifier and a ¾-inch-diameter, 2.5-micron-thick, 24-karat-gold layered Mylar diaphragm. The polar pattern is switched by turning a knurled ring just beneath the mic capsule. Below the knurled ring are two recessed, 3-position microswitches. The top one allows you to select one of two attenuation pads (-15 dB or -25 dB) or a 0 (unpadded) setting; the lower switch allows you to choose one of two highpass filters (at 80 and 115 Hz) or a flat setting. The microphone has a silver finish and weighs less than 6 ounces.

The KSM141 derives its polar patterns by traditional mechanical (porting) means, and switching between the two patterns is also done mechanically — the knurled ring moves a sliding cover that blocks or unblocks vents on the microphone, thus changing the polar response. The polar patterns are clearly marked on the rotating ring, and a very positive detent in the mechanism, as well as a visual notch, eliminates any ambiguity about which pattern you have selected. By the way, the KSM141 makes quite a bit of mechanical noise when you change polar patterns, so be sure to mute or lower the preamp gain before switching patterns.

The KSM141 comes packaged in a nice, hard-plastic carrying case complete with a nylon mic clip and foam-rubber windscreen. The overall fit and finish of the microphone is indicative of high quality and ruggedness. The KSM141 is manufactured in the United States and has a two-year warranty.


I received a pair of KSM141s for this review. All testing was carried out using the following equipment: a Neotek IIIc console, Urei 809 and Fostex NF-1 monitors, D.A.V. Electronics Broadhurst Gardens (solid-state) microphone preamp, Peavey VMP-2 (tube) microphone preamp, and MCI/Sony JH-24 multitrack and Studer A 80 RC 2-track recorders.

The first test I conducted was a comparison of the two KSM141s. By positioning the microphones as close together as possible and then reversing the polarity on one of the mics, I achieved a very high null, indicating that the microphones were well matched. I also checked out the KSM141s on a variety of sound sources.

According to the KSM141's frequency-response plots, in cardioid mode the microphone's low end starts rolling off at around 300 Hz and is down more than 5 dB at 20 Hz. The high end shows a smoothly rising presence boost between 4 and 14 kHz, peaking 2 dB up at 9 kHz. In omnidirectional mode, the low end practically inverts, rising smoothly from 500 Hz to 2.5 dB up at 20 Hz. The high end (in omni mode) shows a broader yet still smooth presence boost spanning from around 2 to 20 kHz and up nearly 3 dB between 6 and 8 kHz.

Acoustic guitar

I miked my Ricardo Sanchis Carpio classical guitar with the pair of KSM141s positioned in an ORTF spaced-pair configuration. A classical guitar with a tight-grained cedar top, the Sanchis Carpio is a well-balanced-sounding instrument with a forward midrange and a pronounced bass register.

The KSM141s sounded best with one placed in front of the sound hole about 6 inches away, aimed somewhat toward the bridge of the guitar, and the second suspended about 12 inches over the guitar and aimed toward the neck near the tenth fret. I experimented with both polar patterns, but preferred the sound of the microphones in cardioid mode for this application.

I liked the mic better on fingerpicked passages — its presence boost helped bring out the detail of fingers on the strings. On strummed passages, though, the KSM141 highlighted the pick sound more than I cared to hear. Overall, the sound was somewhat flat (one-dimensional), shy on the lows, and not particularly true to the sound of the instrument. Then again, given the KSM141's bass-shy response, it could be just the thing for an acoustic guitar with a boomy low end that needs some taming.

Snare drum

Unlike many engineers, I don't much like the sound of a dynamic microphone on a snare drum. Even though the donk sound that typically results is usually punchy and great for driving a reverb, I find that dynamic mics tend to homogenize the tonal differences between snare drums. I much prefer small-diaphragm condenser microphones, which I position close to the shell of the drum, sometimes right at the rim, and occasionally pointed at the head.

I tried the KSM141 in all three positions, both on a standard-size Ayotte Keplinger stainless-steel snare drum and on a maple Ayotte “piccolo” snare. I was a bit disappointed with the resulting sound. It was slower (in terms of transient response) and darker than what I am used to, and overall the sound was a bit boxy and dry — indeed, it reminded me of a dry '70s snare sound. The track was usable, just not my cup of tea.

A quick switch to an Audio-Technica AT4051 — one of my favorites for miking snare drums — showed that to be the case. Interestingly, the KSM141 sounded more like a Shure SM57 than your usual small-diaphragm condenser.


I experimented with both a single KSM141 and a stereo pair on a Rhythm Tech tambourine with chromed-steel jingles. (Incidentally, I didn't particularly care for the mic-stand adapters supplied with the KSM141s, as they were too shallow to thread all the way onto my stereo-miking bar. But I solved that problem easily enough by placing additional locking rings on the bar before attaching the stand adapters.)

In this application, I especially liked the results I got with a single KSM141 in omni mode. Positioned about ten inches away from the tambourine (and routed through the D.A.V. solid-state preamp), the microphone captured a nice bit of room sound along with a good dose of direct jangle. Though I have often found this particular tambourine to sound rather harsh, the KSM141's relatively dark presentation tamed the somewhat nasty nature of the steel jingles and resulted in a nice-sounding track.

Drum overheads

Again using the D.A.V. preamp, I miked the studio's GMS kit from above with the microphones positioned about five feet off the floor and slightly out in front of the bass drum. I set the KSM141s to cardioid mode and positioned them in an XY configuration with one aimed between the snare drum and hi-hats and the other at the floor tom.

I was not favorably impressed by what I heard. Everything sounded somewhat boxy and closed in, and neither the tonality nor the attack captured by the microphones conveyed what the drums actually sounded like. Undaunted, I moved the mics further back into the room. But they still sounded a tad pinched.

Next, I switched the microphones to omni mode. This helped considerably in bringing the sound of the kit together: the low end came up, and overall the frequency content was truer to the drum kit. However, the off coloration and less-than-stellar transient response remained. Both the low end and high end still sounded a bit rolled off, and the midrange had a hard, one-dimensional quality.

Room mic

Using the same setup, I pulled the microphones back into the room about 15 feet from the drum kit. Unfortunately, in this application the KSM141's rolled-off lows and highs and boxy-sounding midrange were even more apparent. Also, the sense of real space — admittedly one of the more difficult things for a microphone to capture — was never really there. I was surprised at how flat and one-dimensional the drums sounded, especially given the fairly live space I recorded them in.

Just to be sure, I double-checked my impressions by substituting a pair of Neumann KM 184s (also small-diaphragm condensers). Though the Neumanns are not my favorites — they have a somewhat bloated-sounding low end to my ear — they are very transparent and provide excellent transient response. At any rate, it took only a few moments of listening to the Neumanns to confirm my impressions of the KSM141s.


I positioned a KSM141 about 4 inches from the top head of my 12-inch Latin Percussion djembe and was pleased by the nice, round tone I heard upon playback. I also got good results by placing a KSM141 slightly inside the open end of the drum. This was one of the more flattering applications for the KSM141 — the microphone's overall midrangy sound was very complimentary to my djembe.

Guitar amp

Emboldened by the KSM141's 170 dB SPL rating (with the 25 dB pad engaged, that is), I fired up my Mesa/Boogie Dual Rectifier amp, plugged in a Fury Baritone guitar, and cranked out some truly wall-rattling tones. With the microphone positioned close to the grille cloth, aimed between the speaker's cone and surround, I got a huge, ballsy sound. However, though tonally the sound was excellent, it still seemed a bit slow compared with the sound of the amp.

A quick switch to a hypercardioid dynamic microphone I often employ on high-decibel amps yielded a less satisfactory sound as far as transient attack was concerned, and the amp sounded smaller to boot. Going back to the KSM141 and switching it to omni mode opened up the sound quite a bit, but also allowed some unwanted interaction with reflections from the floor. I was able to alleviate that problem easily enough, though, by putting a small, thick floor mat in front of the amp. The resulting sound was much more like the amp actually sounded.


The Shure KSM141 is a rugged, well-featured, and versatile small-diaphragm condenser microphone. Having two polar patterns — cardioid and omnidirectional — as well as a choice of low-cut filters and attenuation pads extends the mic's suitability for a range of applications.

Sonically, the KSM141 is not exactly transparent, nor is it airy and open sounding. Rather, it tends toward a darker, drier presentation than other small-diaphragm condensers I am familiar with. In fact, the KSM141 made me think of a Shure SM57 on steroids — it's a bit brighter and faster than that legendary dynamic, but it definitely has a 57 vibe. There's a kind of hard and flat (one-dimensional) quality in the midrange, and both the highs and lows — especially the lows — sound overly rolled off. In addition, the KSM141 does not exhibit exceptional transient response, at least as compared with similar condensers.

Just the same, the KSM141 did a nice job on a variety of instruments. I loved it on djembe, and its dark quality helped smooth out some harshness on a tambourine. Recordists with particularly bright sound sources — or overly bright recording spaces — may find the mic helpful for taming edginess. In general, I liked the KSM141 better in omnidirectional rather than cardioid mode — the lows are much better represented in omni. Still, to my ear the KSM141 does not sound as good overall as certain other comparably priced microphones, and it is considerably more expensive than many other small-diaphragm, electret-type condensers currently on the market.

Richard Alan Salzis a producer, engineer, and composer living in southern Vermont.


condenser microphone
$1,540 (pair)


PROS: Quality construction. Two attenuation pads. Two highpass filters. Quiet. Big dynamic range. High SPL handling. Relatively dark presentation can help tame overly bright or harsh sources. Comes with carrying case, mic clip, and windscreen.

CONS: Low end is underrepresented. Tends toward flat, one-dimensional sound. Electret rather than “true” condenser. Short threading on microphone clip.

Shure Inc.
tel. (800) 25-SHURE or (847) 866-2200

KSM141 Specifications

Elementfixed-charge backplate, permanently polarized (“electret”) condenserDiaphragm¾", 2.5µ, 24-karat-gold layered MylarPolar Patternscardioid, omnidirectionalFrequency Response20 Hz-20 kHz (+2, -5 dB)Dynamic Range131 dBSignal-to-Noise Ratio80 dBSelf-Noise14 dBMaximum SPL145 dB SPL (without pad)Highpass Filters80 Hz, 18 dB/octave; 115 Hz, 6 dB/octaveAttenuation Pads15 dB, 25 dBPower48V phantomDimensions5.75" (L) × 0.80" (D)Weight5.5 oz.