The Pendulum SPS-1
by Michael Ross
Guitar Player Magazine, August 1995

   So you just laid out a couple of grand for a top-of-the-line acoustic that you plan to use onstage. If you perform solo or don't move around too much, you can probably get away with a good stand-mounted mike, But if you're in a band, you'll need a high-quality pickup system - most likely a saddle pickup plus internal mike or a soundhole/saddle-pickup combo - and a good preamp/mixer to blend and EQ the transducer signals. The Pendulum Audio SPS-1 stereo preamp system ($1,095) is the latest addition to this New Jersey based company's line of audio products (Pendulum introduced the first rackmount acoustic preamp in '88). The SPS-1 is a single-rackspace unit designed to be used with just about any configuration of pickups, internal or external mikes, and onboard preamps. Its front panel features two channels, each with independent input-gain attenuation, overload LEDs, three stages of fully parametric EQ, and an in/out switch for instant comparison of flat and EQ'd sounds. The EQ's overlapping frequencies are a smart ideal. The low range covers 35 to 880Hz, the mid 180Hz to 4.2kHz, and the high 840Hz to 19kHz, so you can, say, grab the low band to notch out annoying boom and still boost the upper low end with the mid band.

   The SPS-1 features a pair of pan pots that permit you to place your pickups anywhere in the stereo field, a master-level control, and a phase-reversal switch for controlling feedback. A pair of LEDs indicate the active effects loop and when all outputs (except the tuner's) are muted. A footswitch is provided for both of these functions. The front panel monitor section sports a level control, phase reversal switch,, monitor-input switch (stereo mix or pickup-only for feedback control), and a 1/4" stereo headphone jack.

   The rear panel houses each channel's XLR input, phase reversal switch, external mike switch and gain control, 48-volt phantom-power switch, 1/4" pre-EQ line-in jack, mono effects send/return jack (for effects needed only on one channel, such as compression or additional EQ), and 1/4" TRS-balanced direct-channel out. Channel 1's input-mode switch allows you to send the mike and pickup signals into channels 1 and 2, or combine them in channel 1, thus freeing up channel 2 for an external instrument or vocal mike. Other rear-panel details include a true stereo effects loop and a switch that offers a choice of series or parallel effects. There's also a pair of 1/4" monitor outs, dual XLR master outs, and ground-lift and power switches.

   The Pendulum's unique endpin preamp modules provide studio-quality buffering and stereo mixing at a point as close to the pickups and/or mikes as possible (one module is included with the SPS-1). The module plugs directly into your guitar's endpin jack and come in single pickup, mike and pickup, and two pickup versions. Additional single-source modules run $125; dual-source versions are $165. The latter feature a balance control for the pickup and mike (or second pickup), a master volume, and two recessed gain trimmers. It connects via a special screw-on XLR cable (included) that also supplies the device with power from the rack unit.
We auditioned the Pendulum SPS-1 using a rich-sounding Mossman Tennessee flat-top fitted with a Duncan Sadducer piezo saddle pickup and a crown internal mike. We also had a new Guild D40C cutaway tricked out with a Bartolini 3A soundhole pickup and a Joe Mills internal mike. We ran the Pendulum's output to an SSL 4000E board and listened to the results through Tannoy System 8 and Westlake Audio monitors.

   In this setting, the Pendulum's sound was impressive, to say the least. Its sonic transparency allowed not only the personalities of our guitars to shine through (no generic acoustic sound here), but also the character of the individual mikes and pickups. Preamped through the Pendulum, the Guild's Joe Mills mike sounded beautifully crisp and detailed, and by itself the Bartolini 3A was warm and jazzy. This combination of magnetic pickup and mike yielded incredibly rich, articulate and accurate acoustic tone. Our Mossman also sounded very good initially, but during the course of our testing we had a chance to speak with Counting Crows axman and Pendulum user David Bryson, who suggested rolling the highs off the Duncan to reduce harshness, and reducing the Crown mike's low end for more volume before feedback. After dialing the SPS-1's EQ appropriately, we saw Dave's logic: the Mossman's superb warmth and woodiness was retained, yet we still had the punch and clarity necessary to cut through a loud band. At all times, it was a snap to get exactly what we wanted from the SPS-1, and that says a lot about the care and attention that's gone into this unit's design.

   Bryson's only quibble concerned the module's vulnerability is some live situations - remember, you've got an object about half the size of a pack of cigarettes extending from your endpin jack. Pendulum's floor-mounted and internal units are worth considering if you're a certified acoustic thrasher. Each provides the same mixing/buffering functions. However, the internal module requires phantom power (which means you can't plug the instrument directly into a tuner), and the remote module necessitates a sound-degrading length of cable from the pickup and/or mikes. All modules are compatible with any mixing board that provides 48 volt phantom-power capability.

   The Pendulum SPS-1 is an elegantly designed and superbly flexible acoustic preamp. Its ultra-transparent sound, studio-quality EQ, and advanced features have made it the choice of players such as James Taylor, Phil Keaggy, Leo Kottke, and Bob Weir. Courtesy of its high-quality mike preamps, the SPS-1 can also be used with a DAT or multi-track recorder as a stand-alone stereo mike preamp/EQ for instruments or vocals. At $1,095, the SPS-1 is way more expensive than a Fishman Blender or Rane AP13 - both fine-sounding units in their own right - but its $900 less than Rane's MAP33. In short, if you wish to wring the last drop of tone from your amplified acoustic and can live without MIDI, the SPS-1 is an ideal choice.

   We'd like to thank Gary Brawer Stringed Instrument Repair (San Francisco, California), Paul Robinson at Different Fur Studios (San Francisco, California), Howard Johnson, Mark Slagle, and David Bryson for their assistance.