The ADA Definition Preamp is a preamp/boost pedal for guitar and bass. Its headline feature is a footswitch-activated boost of up to +16 dB, and Vintage Guitar reported that it can deliver boost ranging from clean to full saturation, so it covers everything from a transparent level lift to a push that drives an amp's front end1. Players looking at other options in this category can compare it with the wider field of boost pedals and preamp pedals.
Circuit and what it does to your sound
ADA's design intent, as Vintage Guitar reported it, is a Class A circuit that "turns the first stage of a tube amp into a distortion stage"1. In practice that places the pedal as a preamp rather than a standalone distortion pedal: it shapes how the amp's own gain stages respond, from a clean boost up to full saturation depending on where it is set1.
Because the boost is footswitch-activated, the +16 dB of extra level is available on the fly mid-song, which is the classic use for a boost: lifting a solo above a band or kicking the amp into overdrive for a heavier section1.
Input and power
The pedal's input is specified at 3 megohms with a low-capacitance input1. A high input impedance of this kind is intended to avoid loading down a guitar's pickups, which is where treble loss usually comes from when a pedal sits first in the chain.
Power runs from 9 to 18 volts DC1. The 9V end of that range suits standard pedalboard supplies, while the 18V option is there for players whose supply offers a higher voltage rail.
Vintage Guitar's report covers both a guitar and a bass version of the Definition Preamp/Boost, so bass players considering it alongside other bass pedals have a dedicated option in the same announcement1.
Build
The pedal is housed in an all-steel enclosure1, the standard hard-wearing choice for a pedal meant to live on a floorboard underfoot.
Questions
How much boost does the ADA Definition Preamp provide?
Vintage Guitar reported that the Definition Preamp offers a footswitch-activated boost of up to +16 dB. That boost is engaged from the footswitch, so a player can lift the pedal's output for solos or louder passages and switch back down without touching the controls.
What voltage does the ADA Definition Preamp run on?
The pedal operates on 9 to 18 volts DC, according to Vintage Guitar's announcement. That range lets a player run it from a standard 9V supply or at a higher voltage where a pedalboard power supply offers one.
Is the ADA Definition Preamp a distortion pedal or a clean boost?
It is a preamp/boost pedal rather than a dedicated distortion, but Vintage Guitar described its range as running from clean to full saturation. Its Class A design is intended to turn the first stage of a tube amp into a distortion stage, so it can act as a clean lift or push an amp into overdrive depending on the setting.
What is the input impedance of the ADA Definition Preamp?
Vintage Guitar reported an input impedance of 3 megohms with a low-capacitance input. A high input impedance like that is designed to keep a guitar's pickups from being loaded down, which helps preserve high-frequency detail going into the pedal.
What is the ADA Definition Preamp enclosure made of?
The pedal is housed in an all-steel enclosure, as reported by Vintage Guitar when the pedal was announced.
Sources (1)
- ADA Offers Definition Guitar and Bass Preamp/Boost, Vintage Guitar magazine, 2014-11-27