Pigtronix brings Acoustic Guitar tone to life with Bob Weir Real Deal Signature Preamp pedal

Bob Weir’s Real Deal Acoustic Preamp by Pigtronix (RRP £349) provides crystal-clear, super-loud acoustic guitar tone, while faithfully maintaining the organic wooden sound of the instrument like no other pedal has ever done. “A real acoustic guitar has three-dimensional depth. The only way to capture that is with a microphone,” says Weir. “We’ve figured out how to cut out 90% of the feedback that comes with the microphone, whilst keeping the depth and dimensionality at appreciably high volume levels. We think you’re gonna like this.”

In collaboration with long-time Grateful Dead tech guru and personal front-of-house engineer, Mike McGinn, Weir and Pigtronix developed the Real Deal in an effort to crank Bob’s acoustic guitar loud enough in a live mix, whilst retaining the natural, unplugged sound of the instrument. The technology developed to achieve this goal employs a pair of complimentary filters to split the acoustic guitar signal into low and high frequency bands, with independent preamp gain applied to each signal path. A mastering stage then combines the various inputs into a single mono output, resulting in a powerful world-class acoustic guitar tone.

Bob Weir challenged Pigtronix to design a pedal to perform this unique type of processing using a low-noise, all-analog circuit to deliver the ultimate live acoustic guitar sound. The engineering challenge of recreating a realistic, amplified acoustic guitar sound is no small undertaking; to begin, the cutoff points of the two filters must be precisely matched and calibrated to avoid undesirable dips or bumps in the frequency response at the pedal’s output. Secondly, in order to optimise the acoustic sound from venue to venue, and guitar to guitar, the cutoff points where the two filters overlap have to be variable across a huge frequency range.

As a solution, Pigtronix created a totally unique tracking filter, allowing the musician to adjust the cutoff point of both filters with a single knob, sweeping over a full decade of frequency range from 300 Hz to 3 kHz. The analog filter array – at the heart of the Bob Weir’s Real Deal acoustic preamp – uses Pigtronix custom-made optical components and 18VDC power to achieve the ultra-low noise and high headroom required when processing acoustic guitar.

Bob Weir’s Real Deal acoustic preamp is universally-compatible with any type of acoustic guitar pickup – from a simple, passive piezo element, to complex active systems that use internal microphones, contact elements and/or magnetic pickups. A Source switch determines whether the high and low bands are fed by independent sound elements (such as mic and piezo installed in one guitar) or a single pickup, that is then split and sent through both filters. Single-source mode allows the Real Deal to be used to process the sound of an electric guitar or any other instrument. An additional TRS balanced input, equipped with switchable 48V phantom power, allows external microphones of all types to be incorporated as well.

“Bob Weir’s one-of-a-kind sonic ambition has challenged the Pigtronix design team to reach beyond the realm of conventional guitar effects,” says Pigtronix president David Koltai. “As an artist and a mentor, Bob has inspired our most cutting-edge work for over a decade. Pigtronix is honoured to have been selected to contribute to Bob’s continuing legacy innovation, fulfilling the promise of an analog future where acoustic guitar can be made to sound intimate and wooden, even when cranked up to rock concert volume levels.”

Bob Weir’s legacy of sonic innovation dates back to the late 1960s, when the Grateful Dead and their associates revolutionised the technology of live sounds, redefining the rock & roll experience. Over 50 years later, now in partnership with Pigtronix, Bob Weir is still innovating. 


  • Single (TS) or dual-source (TRS) input
  • Balanced (TRS) input for external mic
  • Low-noise 24db/octave optical filters
  • Crossover sweeps from 300Hz to 3kHz
  • 60db gain on microphone channel
  • Phantom power & phase inversion
  • 18VDC power supply included