Royer Labs SF-1

Royer Labs is a small company dedicated to reviving ribbon microphones for the digital-recording era. I reviewed the company's flagship mic, the R-121,

Royer Labs is a small company dedicated to reviving ribbonmicrophones for the digital-recording era. I reviewed the company'sflagship mic, the R-121, for the May 1999 issue of EM, andI was so impressed that I purchased one for my studio. Since then,that mic has acquired most-favored status at the studio for anumber of applications, especially miking guitar amps and brassinstruments. My colleagues were impressed, too, and honored theR-121 with an Editors' Choice award in 2000.

The inspiration for the SF-1 came from the Speiden SF-12, astereo coincident ribbon microphone originally hand built by BobSpeiden but now manufactured by Royer (see Fig. 1). TheSF-1 is the mono version of the SF-12 — if you sawed an SF-12in half and doubled the electronics, you would essentially have twoSF-1s.

The SF-12 and SF-1 have thinner ribbons than the R-121 (1.8µm compared with the 121's 2.5 µm) and different magnetstructures. According to the manufacturer, those design aspectscontribute to superior transient response (for which ribbon micsare already prized) and improved high-frequency response, albeitwith increased fragility of the ribbon element itself. Of course,all ribbon microphones need to be shielded from powerful blasts ofair and handled with care. The SF-1's output level is comparable tothat of other ribbon mics, requiring 15 to 20 dB more gain than anaverage condenser mic.

Like its predecessors, the SF-1 comes in a beautifully craftedwood box with a nylon mic clip and a lifetime warranty to theoriginal owner (for repair or replacement at Royer's option). Themic body is fashioned from ingot iron and has a matte black finish.Optional accessories include the Audio-Technica AT-84 shock-mount($72), which Royer supplied for this review; a PS-100 metal-meshpop filter ($47.50); and a Sonosax SX-M2 stereo mic preamp($1,250), which Royer also supplied. Royer sells the preamp as anaccessory because of its high-gain and low-noise characteristics,which are desirable for ribbon-mic use. The SX-M2 is a well-built,portable, and compact unit not much larger than a Sony Walkman. Itprovides 76 dB of gain and can be powered by battery or DC current.The SX-M2's performance lived up to its impressive specs,exhibiting very low noise and a somewhat smoother sound than mymain test preamps.


To get a sense of the SF-1's sonic character, I did somecomparison testing. I set up a three-mic cluster: the SF-1, a RoyerR-121, and alternately a Coles 4038 ribbon mic and an Oktava MC 012small-diaphragm cardioid condenser mic. I used BLUE Kiwi microphonecables and Focusrite Green preamps and recorded to a Sony PCM-8008-track digital recorder.

First, I performed a standard loudspeaker test. Although theR-121 did work some magic on the bass end of my boom box source,the SF-1 was more faithful to the source on a selection of mixes.The SF-1 highlighted ambience and percussive details pleasantly;after a number of listening passes, I rated the SF-1 tracks as thebest of the group.

Frequency charts posted by the manufacturer show the SF-1'sresponse deviating less than 3 dB from 40 Hz to 15 kHz; theresponse is flatter than the R-121's, which a comparison of the twocharts makes clear (see Fig. 2). Some EQ sweeps confirmedthe flatness of the SF-1's frequency response — it was easyto hear the effects of boosting in sweeps throughout the bass andtreble ranges, and there were no evident weak or dead spots.However, in this test and on instrument tracks, I noticed a bump inthe SF-1's response around 200 Hz.

Next, I compared the SF-1's off-axis response to that of theother mics by positioning the boom box several feet away at about a90-degree angle to the mic cluster's side. Impressively, the SF-1retained solid low-end characteristics that were lost on the R-121and the small condenser. Both mics also emphasized unusual timbresin the source, indicating a less-than-flat response, and soundedthin or diffuse.

Last, I compared the two SF-1s to hear how similar they sounded.For the sake of thoroughness, I used three solid-state preamps: theSonosax SX-M2, a Focusrite Green, and a Sytek MPX-4. I perceivedonly a minor difference in the high-end “air” betweenthe pair of SF-1s. Other than that, the microphones soundedidentical and perfectly matched.


For perspective, I left the mic cluster intact for theinstrument tests. First up was an acoustic guitar strummed andfingerpicked at close range. The SF-1 sounded flatter than theR-121 but overall was less flattering to the instrument: althoughthe high end was slightly clearer, the bass notes soundedindistinct. The Royer mics were comparable in terms of self-noise(very low) and preamp gain required (about +55 dB). If I had tochoose between the two on acoustic guitar, I would opt for theR-121's tangy flavor over the SF-1's relative neutrality. However,of the three microphones in the cluster, the Oktava MC 012condenser mic was my favorite in this application.

On a bright, close-miked acoustic slide-guitar part, the SF-1'shigh end was closer in character to the Oktava 012's. But there theribbon mic's softer sound was an advantage, despite theduller-sounding upper range and the somewhat boomy and unfocusedlows. With both mics strapped in the AT-84 suspension shock-mounts,the SF-1 proved to be more immune to foot stomping and stand-bornevibration than the R-121.

At a distance of two feet, the SF-1 provided a full low end andrealistic highs for an assortment of guitar styles. A cut at 220 Hztook out a slight boominess in the sound and let my inexpensiveHyundai guitar sound much richer than it did through the othermicrophones. Not surprisingly, in the high end above 8 kHz, therewas still no comparison with the crisp timbre of the Oktavacondenser.

SE-1 Specifications Acoustic Operating Principle electrodynamic pressure gradient Generating Element 1.8 µm aluminum ribbon Polar Pattern bidirectional (figure-8) Frequency Response 30 Hz-15 kHz (± 3 dB) Sensitivity -52 dBV (1v/Pa ±1 dB) Output Impedance 300• @ 1 kHz (nominal) Maximum SPL >130 dB Dimensions 5.6" (L) × 1" (W) Weight 9.3 oz.

During a session with a Martin Backpacker mandolin, the SF-1added a warm, supportive character. The performer, guitaristMichael Bizar, praised the microphone's qualities, and I agreedthat the SF-1 warmed up this instrument very nicely.


Because the R-121 has become a first-pick microphone forrecording electric guitar at my studio, I was eager to see if theSF-1 could match or perhaps even beat it. It didn't. Positionedabout two feet from a cranked Fender tube amp with two 12-inchspeakers, the SF-1 conveyed a hollow midrange and too much low-endmud. A 4 dB boost at 2.5 kHz brought the SF-1 closer to the R-121'scharacter, but the SF-1 still didn't have the presence andready-to-rock tone that have made the R-121 so popular amongguitarists and engineers.

Likewise, on a mellow, amplified jazz guitar, the SF-1 was murkysounding compared to the other ribbons. In this application, itsextended high end brought out some amp noise but no specialqualities. As much as I appreciate the SF-1's virtues as a flat andextremely warm mic, for electric guitar I usually want a mic withsome attitude. The SF-1 has a neutral quality that makes the R-121and Coles 4038 seem aggressive in comparison.

On the other hand, during a session with guitarist John Shiurba,the SF-1 worked wonders on a small, solid-state Vox guitar amp. Itmanaged to add punch and authority yet smooth out rough edges onthe challenging array of textures Shiurba created. I also tried theSF-1 directly on another of Shiurba's guitars, an unamplifiedhollow body, as he played in the same room with other musicians.This time the mic provided incisive high-end detail. Also, themic's off-axis pickup, which was readily apparent when I brought upthe acoustic instrument track in the ensemble setting, wasremarkably uncolored. Often during multiple-mic sessions, bleedfrom condenser mics creates muddiness, unwanted room sound, andnarrow-band coloration throughout the frequency range. But in thiscase, the leakage was not a problem, especially after I equalizedsome “thump” out of the guitar with a 4 dB cut at 200Hz.

I experimented with the SF-1 on two keyboard-and-amp rigs (solidstate) as the players ran the gamut of samples, synth patches, andindustrial noise. During tracking and mixing, I was impressed bythe SF-1's immediacy and its sympathetic treatment of pure synthtones, high-resonance peaks, and low-end material in the 40 to 80Hz range. I didn't compare any other mics during this session, andI didn't feel compelled to, either. Under demanding conditions theSF-1 reproduced diverse, full-frequency sources perfectly, with noharshness or dulling. In the mix, the tracks needed minimal EQ— just a small amount of 4 to 8 kHz sweetening or theoccasional low- or upper-midrange cut around 1 kHz.

Brass instruments are a traditional favorite for ribbon miking.I tried the SF-1 on trumpet and received great results. Despitesome raspiness in the high end, the SF-1 gave the trumpet a biggersound and an enhanced sense of low-end air movement compared withthe R-121 and Coles 4038 ribbon mics. On open horn, the Coles 4038had less fizzle, but the SF-1 displayed a touch more warmth. OnHarmon-muted trumpet, the SF-1's overall response was a real boon,supplying clear, high-harmonic richness and an authoritative lowend.


The SF-1 improves markedly on the R-121's already formidablecapabilities as a percussion mic. On tambourine, the R-121 soundeddull and crunchy in comparison, and the small-diaphragm condensersounded a bit too bright and piercing. The SF-1 rendered thetambourine in a detailed and surprisingly listenable way; indeed,it sounded superior to any ribbon mic I've tried in thatapplication.

On shaker, though, the Oktava MC 012 was my favorite, and theSF-1 offered obvious improvements on the R-121 in terms of high-endpickup and transparency. Yet on jingling keys, miked from two feetaway, the SF-1 proved much more accurate than the condensermicrophone. Interestingly, when I moved the keys to about one footfrom the mic cluster, the SF-1 sounded almost identical to theOktava 012. For that source sound, I found the condenser's slighthigh-end advantage to be a sonic disadvantage, because it providedtoo much stimulation to my middle-aged cilia. The SF-1 is truly thefirst ribbon microphone I have ever considered for delicatehigh-end percussion duties, and I looked forward to trying it ondrums.

Fortunately, fellow engineer Karen Stackpole was reviewing anAyotte drum set for Onstage (EM's sisterpublication), so I was able to evaluate the SF-1 pair in XYcoincident and split-overhead configurations. At approximatelyseven feet above the floor, the XY and spaced arrangements of theSF-1 pair underrepresented the cymbals and sounded too tubby.Compared with the Oktava 012 XY pair, the SF-1 grabbed a greatsnare sound and painted a much more robust and immediate picture ofthe kit's drum portion. But even with EQ, the cymbal sound was justtoo dull.

Remembering my experience with the key test, I moved thesplit-overhead SF-1s closer — nearly on top of the left andright cymbal clusters — so that no cymbal was more than threefeet from the mics. Suddenly, the sound of the drums snapped intofocus: not only was there much more detail from the cymbals butalso a remarkable combination of punch and clarity also emergedfrom the floor tom and snare. With a little high-end boost, thatsetup could provide a big and distinctive sound for jazz or funkrecording.

I also experimented with the SF-1 as a mono drum overhead,comparing it with a single Oktava 012. Placed above the center ofthe kit and about five feet from the floor, the SF-1 picked upviable cymbal sounds and captured a huge snare tone that soundedmuch truer than what the condenser mic captured.

When raised two feet higher, the single SF-1 produced a soundsurprisingly comparable to the Oktava 012. With a high-frequencyshelving boost of +3 dB and a broad low-end cut of 3 dB at 200 Hz,the SF-1 nearly matched the small-diaphragm mic's crispness andprovided a butt-kicking low end to boot. It took a little gettingused to, but toward the end of the listening session, I reallybegan to like the full sound emerging from the SF-1, and I decidedto experiment with it further in upcoming sessions.

During the listening evaluation, Stackpole noted that the SF-1sounded “better and brighter when the mics got closer, andthey did seem to give the drums some beef.” Although in theend Stackpole preferred the drum sound captured by thesmall-diaphragm condenser pair, she remarked that “the Royersare definitely usable — not a bad sound, justdarker.”


As a frequent and enthusiastic user of the Royer R-121, Iapproached this review with great curiosity. Could the SF-1actually improve upon the R-121's upper high-end response? Theanswer is an unequivocal and resounding yes. Is the SF-1 a greatribbon mic? Once again, the answer is yes. As I learned from mytests, the SF-1 does some things better than other ribbon mics(including the R-121). But not surprisingly, there are also thingsit doesn't do as well.

I was impressed by the SF-1's potential as a percussion and drummic. With proper placement and a few EQ nudges, its clarity rivaleda small-diaphragm condenser mic that I regularly employ. The SF-1also sounded wonderful on trumpet, and I would expect it to performas well or better on other members of the brass family. Inaddition, I was literally moved by the superb bass response andpunch of the SF-1 — it reproduced powerful low-end airmovement in a way that only a few high-end condensers can.

With this new entry into the underpopulated world ofstudio-grade ribbon mics, Royer has created yet anotherdistinctive, versatile, and great-sounding microphone. Not only isit an excellent complement to the R-121, but the Royer Labs' SF-1also has a voice and capabilities all its own.


Royer Labs

ribbon microphone


PROS: Flat frequency response. Better upper high-endresponse than most ribbon mics. Superb bass response and punch.Great for some small percussion. Viable for drum set. Excellent onkeyboard amps and brass instruments. Remarkably uncolored off-axisresponse. Low self-noise. Beautifully crafted wood case. Lifetimewarranty to original owner.

CONS: As with most ribbon mics, attention to placementand EQ required for best results. Increased fragility due to thinribbon. Prominent boost around 200 Hz noted on many sources.Low-end response can sound murky or unfocused on some acoustic andelectric guitars.

Royer Labs
tel. (818) 760-8472