The Audio Kitchen The Small Trees is an all-valve, Class A clean boost and line driver: a pedal that lifts a guitar or bass signal by about 16dB without changing its character, and then drives it down the line with a tube output stage. It is built around a single ECC82 valve and runs from a 12-volt adaptor, with one Gain knob doing all the work12. Guitar World's reviewer, Trevor Curwen, described it as "an all-valve Class A clean boost based around a single ECC82 and powered by a 12-volt adaptor. There's 16dB of clean boost"2.
What it does to your signal
The circuit has two stages, each with its own job:
| Stage | What it does |
|---|---|
| First stage | 16dB of clean boost1 |
| Second stage | Valve line driver, for pushing the signal down a long cable or into studio gear1 |
The measured distortion is low: less than 0.3% with an input of 0dBm, which is what keeps the boost clean1.
Audio Kitchen describes the effect as "a magical lift to the sound that creates its own space in a mix," and points to uses beyond guitar amps1:
- Creating an exciting DI guitar sound in the studio
- Adding harmonics to a bass signal
- Enlivening the output of a soft synth or sampler
The single Gain control is marked so that 12 o'clock is unity gain, which makes it easy to judge exactly how much level you are adding1.
Where it came from
The Small Trees began life inside another Audio Kitchen pedal. Users of the company's TBTs kept telling the maker that the green side of that unit was invaluable as a guitar and bass front end, so Audio Kitchen developed it as a standalone pedal1. Essentially, The Small Trees is the green side of the TBTs housed in a smaller enclosure and powered via a 12V adaptor1.
The DI version
There is a sibling pedal, the Audio Kitchen Small Trees DI, which Audio Kitchen describes as a "Class A, all valve, clean gain boost, line driver and DI." The two versions line up like this3:
| The Small Trees | Small Trees DI | |
|---|---|---|
| Gain control | Unity at 12 o'clock3 | Unity at 12 o'clock3 |
| Boost | ~16dB3 | ~16dB at line output3 |
| Distortion | Less than 0.3% at 0dBm input3 | Less than 0.3% at line output3 |
| Power | 12VDC @ 1000mA3 | 12VDC @ 1000mA3 |
| Enclosure | Die-cast aluminum3 | Die-cast aluminum3 |
| DI output | None | Sowter transformer3 |
As the maker puts it, "Suffice it to say, FoH will love you"3.
Power, size and practicalities
The power requirement is the one thing that rules out casual placement on a pedalboard. The Small Trees needs 12VDC at 1000mA1, which is beyond what a standard 9V output on most pedalboard supplies delivers, and it is far too current-hungry to share a daisy chain.
The Small Trees runs on 12VDC at 1000mA, not the 9V that most compact pedals use. It needs its own suitable adaptor and will not run from a typical 9V pedalboard supply output or a battery.
Physically it is compact for a valve pedal:
| Specification | Value |
|---|---|
| Dimensions | Approx 116mm x 91mm x 55mm (4.6" x 3.6" x 2.2")1 |
| Weight | 482g (1 lb)1 |
| Enclosure | Durable die-cast aluminum1 |
The price from the maker is £325 + VAT, or £390 including VAT, for the standard BLUE tolex finish, excluding shipping. Audio Kitchen notes that VAT is only applied to sales within the UK, and buyers outside the UK are subject to import tax at their customs border1.
What reviewers said
Guitar World's review, by Trevor Curwen, confirms the core specification: the all-valve Class A circuit, the single ECC82, the 12-volt adaptor power and the 16dB of clean boost2.
Videos
AudioKitchenAmps
Joe Perkins
Questions
Does the Audio Kitchen Small Trees use a tube?
Yes. The Small Trees is an all-valve, Class A clean boost built around a single ECC82 double triode tube. It runs the valve at higher internal voltages from a 12VDC adaptor rated at 1000mA, which is why it needs its own supply rather than a standard 9V pedal supply or a daisy chain.
How much boost does the Small Trees give?
About 16dB. The first of its two stages provides 16dB of clean boost, and the second stage acts as a valve line driver. The single Gain knob is set so that 12 o'clock is unity gain, so anything past that point pushes the level up.
What power supply does the Small Trees need?
A 12VDC adaptor rated at 1000mA. That is a higher voltage and current draw than most compact pedals, so it will not run from a standard 9V pedalboard supply output or a battery.
Is the Small Trees a boost or a preamp?
Both, in a sense. Audio Kitchen describes it as a clean boost and a valve line driver: two stages, the first giving 16dB of clean boost and the second driving long lines or downstream gear. Players have also used it as a guitar and bass front end.
Where is the Audio Kitchen Small Trees made?
Audio Kitchen builds The Small Trees by hand at its workshop in West London, in the UK, in a die-cast aluminium enclosure.
Sources (3)
- Audio Kitchen, musically inspiring amp design, Audio Kitchen
- Effectrode Blue Bottle Inductorized Booster review, Guitar World, 2020-08-20
- Audio Kitchen, musically inspiring amp design, Audio Kitchen
