�������� ���������������

We first met Boris Drazic and ZoranTodorovic of Canadian audio firm SonicFarm in our July 2013 issue, when welooked at the 2DI4 tube direct box and Inoted Sonic Farm’s iconoclastic design phi-losophy. In a nutshell: As long as the endresult sounds right to their ears, they don’tcare if it takes tubes, transistors, IC chips,or op amps to get there—these guys willdo whatever it takes to get the right tone.They are also unconcerned with recreatingclassic gear of yesteryear, so you’ll find noclones or copies on this Farm.Sonic Farm products are all about tonal

choices and versatility. The company’sflagship device, the Creamer, offers multi-ple flavors of solid-state and tube tones inone box, their Creamliner tube line con-ditioner offers a choice of pentode or tri-ode modes, and a similar design wasused in the 2DI4. The Silkworm preampkeeps this tradition going, giving you mul-tiple flavors of sonic coloration; it’s SonicFarm’s first all-solid-state product, and itsfirst 500 Series module.

Look and feel, fit and finishThe Silkworm is a single-channel 500

Series microphone preamp/instrumentDI. It is well built from top to bottom andis one of the heavier 500 Series modulesI have ever used. This is due to therebeing a pair of large transformers insideits enclosure.The Silkworm features all-metal con-

struction and is clothed in the same redand black enamel finish as the rest of theSonic Farm line, with white lettering andaccents. Its large white Gain knob has anice balance of glide and resistance andits toggle switches are similarly solid andfirm.The Silkworm is fully enclosed on all

sides, which is how I wish all 500 Seriesdevices were built. A full casing makes it somuch easier to seat in your 500 Series rack(in my case, it’s the Radial EngineeringWorkhorse that I use for most reviews), andit keeps internal components from gettingbent or bumped when doing so.

The signal path and some specsThe Silkworm uses a fully discrete op

amp gain stage; there are no capacitorsanywhere in its all-DC signal path; SonicFarm says this results in a natural low endfree of phase shifts, “something no tube pre-amp can do.” It also makes use of servocontrol for minimal DC offset. Its signal pathstarts with a low-distortion Cinemag trans-former input stage, and then offers a choiceof output stages. You can choose betweena second Cinemag Fe output transformer ora balanced IC-based output stage.Additionally, the Silkworm offers multiplecharacter voicings as well; we’ll talk aboutthe Vibe switch in a moment.The Silkworm’s maximum microphone

gain is 66 dB while its instrument input offersup to 42 dB. Its maximum output level is 28.7dBu. Further tech specs include gain stageTHD under 0.0005% at 1kHz, minimum out-put load of 600 ohms. See the Sonic Farmwebsite for detailed Total Harmonic Distortionfigures as a function of frequency for the inputand output transformers.

Controls and features explainedThe Silkworm’s Gain knob trims the

input signal with respect to the initial levelset by a 3-position toggle switch markedH (high), M (medium) and L (low). Theunit is equipped with a single bi-color LEDwhich glows from green to red to indicatesignal and clipping.There are two columns of toggle controls

down the front of the unit. The left columnhas the aforementioned Level switch, inbetween two switches marked SS/OT andVibe. The SS/OT switch chooses the outputstage signal path, either IC only (SS standsfor “solid state”, a bit of a misnomer sincethe Silkworm has no tubes anyway) or withthe output transformer in place (OT). TheVibe switch uses changing capacitance andresistance to alter the sonic character of thesource. The switch is cryptically labeled S, Pand W. The P setting stands for Presence,and is essentially the Silkworm’s most neu-tral, flat frequency response. S stands forSmooth; as its name implies, it offers a

B Y P A U L V N U K J R .

Sonic FarmSilkworm 500 Series Mic PreampTweakable tonal response gives this 500 Series pre extra flexibility

Excerpted from the September edition of RECORDING Magazine 2014©2014 Music Maker Publications, Inc. Reprinted with permission.5408 Idylwild Trail, Boulder, CO 80301 Tel: (303) 516-9118 Fax: (303) 516-9119 For Subscription Information, call: 1-954-653-3927 or www.recordingmag.com

��� ����������������� ��

round rolled off top end. The last choice isW, which stands for Warped; it opens upthe top end slightly with an 8–10 kHz boost.The right column of controls includes more

mic preamp standard fare such as 48Vphantom power, phase (polarity), and amic/instrument switch that selects betweenmicrophone input and a 1/4" instrumentinput on the front panel. Also on this side isa 15 dB pad switch; while pads are usual-ly nothing to write home about, this one isnot only pre-input transformer but it also low-ers the microphone impedance as well.

In useI put the Silkworm to work immediately at

the start of two new recording projects,both primarily acoustic in nature. The firstwas a world-music influenced version of theProclaimers song “500 Miles (I WannaBe)”. Other than the multi-miked groupbacking vocals, I tracked the whole songentirely through the Silkworm, one soloinstrument at a time. I instantly favored theforward push of the W setting coupled withthe OT output setting, and that is where itstayed for the whole song. Instrumentstracked included multiple acoustic guitars,lead vocals, three separate Irish bodhrans,and a kick drum. The results were full andsolid, and the Silkworm did well to capturethe raucous nature of the track.The next Silkworm session was a young

female singer/songwriter with a Martinacoustic guitar played as she sang. Forher vocal, I stayed with the OT output set-ting but this time put the Vibe switch in Pmode. I used the Silkworm with aPearlman TM-47 mic (also reviewed inthis issue) and was very pleased with theweighty and sonically pleasant nature ofthe recording.I did try the S setting for both sessions

and found it a tad too rolled off for mytastes. I later found this setting useful onshrill sources or for imparting a purpose-ful dark vibe to a track.

Sounds like?I find this a hard mic preamp to pigeon-

hole as sounding like this pre or that pre.On its website, Sonic Farm mentions a sim-ilarity to a Neve 1073LB, but since I don’thave one on hand to compare it with, Iwon’t go out on a limb and corroboratethat claim. I do have a Great RiverMP500NV mic preamp in my collection,which is known to hint at a Neve flavor,and I can say that these two preamps didshare sonic similarities. Overall I would eas-ily put the Silkworm in the classic consolemic pre category with a solid forward feel.Even though it has the option of a trans-

formerless output, thanks to its trans-formered input it still has weight and char-acter. Some say that switching off thetransformer output gives the Silkworm thesound of a completely clean “wire withgain” preamp as you would expect from

firms like Millennia Media, GML, orGrace Design, but as a longtime Millenniaowner I hear—and like!—the difference.Removing the transformer in the output

stage widens the sonic spectrum by a hairand subdues the weight of the mids whilegiving a touch more openness to the lows.As such, it is similar to designs by Dakingand Focusrite, putting it in great company.

ConclusionsIf I have any small complaint at all

about the Silkworm, it would be with howits Vibe and output staging controls arelabeled. I mentioned how odd it is to havea “Solid State” setting on a device with notubes. In addition, on the Vibe control, S isindeed Smooth, but the neutral settingshould be called that, not Presence, whichmakes one think of enhanced highs andhigh mids. For that tonal response, insteadwe have “Warped”, which implies distor-tion or other strangeness that isn’t there.[Zoran Todorovic agrees. The originaldesign had a “Warm” setting; early testusers asked that it be tweaked to the cur-rent sound, but the front panels werealready made... so the Sonic Farm folksjust changed what “W” meant.—Ed.]That quibble aside, what I like most

about the Silkworm is that it retains itsbase sonic signature, while the outputand Vibe switches offer great variationson a theme rather than trying to be two orthree mic preamps in one. Users will hap-pily live with the naming conventions ifthey have a chance to use a preamp thatsounds this good!The Silkworm is a great-sounding, solidly

built, and highly versatile entry into theworld of 500 Series preamps. It evokes aclassic preamp sound with being too heavy-handed, and its wonderful sonic alterationstake it over the top. Another product towatch for, from a firm to watch for!

Price: $700

More from: Sonic Farm, www.sonicfarm.com

Excerpted from the September edition ofRECORDING Magazine 2014©2014 Music Maker Publications, Inc. Reprinted with permission.5408 Idylwild Trail, Boulder, CO 80301 Tel: (303) 516-9118 Fax: (303) 516-9119 For Subscription Information, call: 1-954-653-3927 or www.recordingmag.com