The BO Effects OxyTone EPX is a two-channel low gain overdrive pedal from BO Effects, a French company. It puts two circuits in one box: one channel is based on the preamp section of the Echoplex EP-3 tape echo, and the other replicates the maker's popular Oxy Drive circuit, slightly modified to sit well with the preamp. Each channel has its own footswitch, and Delicious Audio's Paolo De Gregorio describes the two as fine-tuned to interact when stacked, spanning boost to overdrive1.
The two channels
The preamp channel takes its cue from the Echoplex EP-3, a tape echo unit whose preamp was prized as much for its tone conditioning as for the echo itself. Dunlop notes that guitar players were hooked by the way the EP-3's preamp sweetened their sound, often running it into an amp with the echo effect not engaged2. MusicRadar's Trevor Curwen describes the EP-3 as a tape echo with a FET-based preamp, used "before your amp - but not necessarily with the echo effect engaged"3. Aion FX, which builds its own EP-3 preamp recreation, records that the original ran on a 20V supply and came in two versions: an early version that was brighter, and a later version that was a little darker and fatter, the difference being a single capacitor added to the first JFET stage4.
On the OxyTone EPX, that preamp circuit gets a volume control and, notably, a gain control that Delicious Audio says will bring a break and extra grain to the popular preamp sound1. The drive channel is described as a transparent low gain overdrive based on the OxyDrive, tuned to work with the preamp channel1.
The controls
The pedal carries three knobs per channel, one white and two black on each, plus the two footswitches1.
| Knob | What it does |
|---|---|
| Preamp | Determines the output level of the preamp1 |
| Body | Controls the overall tone of the signal1 |
| Dirt | Finely adjusts the clipping ratio of the signal1 |
| Level | Determines the output level of the overdrive1 |
Delicious Audio describes the pedal's overall response as running from clean boost to overdrive through the gain boost, responding well to attack on the strings and playing nuances1. For where this kind of circuit sits, see the site's pages on Preamp Pedals, Boost Pedals and Overdrive Pedals.
Power and build
The OxyTone EPX has no internal housing for a battery, so it needs an external supply. It takes a standard Boss-style 2.1mm center negative DC input at 9 to 18 volts, and the maker notes that running at higher voltage brings more body and gain1.
The pedal is built in an aluminum housing, which Delicious Audio describes as offering lightness and robustness for a pedalboard1. The components list includes PETP and NOS Cornell Dubilier Silver Mica capacitors1. The pedal is manufactured, wired and assembled by hand in France1.
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Questions
Does the OxyTone EPX take a battery?
No. According to Delicious Audio's product page, the pedal has no internal housing for a battery, so it runs only from an external power supply. It uses a standard Boss-style 2.1mm center negative DC input and accepts 9 to 18 volts, with the maker noting that higher voltage brings more body and gain.
What is the EP3 Echoplex preamp sound?
The Echoplex EP-3 was a tape echo unit whose FET-based preamp was prized as much for its tone conditioning as for its echo. Players ran it into an amp with the echo off simply to sweeten their sound. Aion FX notes there were two versions: an early, brighter version and a later, darker and fatter one, the difference being a single capacitor added to the first JFET stage.
Is the BO Effects OxyTone EPX true bypass?
Yes. Delicious Audio describes the OxyTone EPX as having a true bypass on/off switch with no degradation or loss of signal when the pedal is off.
Where is the BO Effects OxyTone EPX made?
BO Effects is a French company, and the OxyTone EPX is manufactured, wired and assembled by hand in France, according to Delicious Audio's product page.
Sources (4)
- BO Effects OxyTone EPX Low Gain Drive, Delicious Audio, 2021-11-17
- ECHOPLEX® PREAMP, Dunlop (jimdunlop.com)
- Dunlop Echoplex Preamp review, MusicRadar, 2018-08-24
- Ares Vintage Preamp / Echoplex EP-3 Preamp, Aion FX, 2019-10-18
