The PastFx OG-1 Overdrive is a limited-run overdrive pedal that recreates the early version of the Boss OD-1 and then adds an SD-1 mode on top of it. PastFx describes it as "a PastFx limited run of the 3403 early version OD-1 with bonus SD-1 addition"1. The pedal was built around the 14-pin 3403 op-amp IC that the original early OD-1 used, a chip Guitar Pedal X calls "next to uobtanium now"2. The initial motivation, according to PastFx, was to reward "PastFx V.I.P" customers with something unique to thank them for their loyalty1.
For a player, that means one box that covers two classic circuits: the OD-1's overdrive, and the SD-1's overdrive with a working tone control. Guitar Pedal X describes the pedal as combining "OD-1 and SD-1 modes with a rare JRC3403 14-pin OpAmp, clipping, Presence, Tone and bass options"2.
An early OD-1 with an SD-1 mode added
The Boss OD-1 OverDrive was produced from 1977 to 1985 and is now discontinued3. It came in two versions: the original 1977 "quad version" and a later "dual version"4. The early version used a 14-pin op-amp, the RC3403, which TONEHOME calls "fantastic sounding"3. Aion FX notes the OD-1 was a precursor to the Tube Screamer4. The OG-1 recreates that early 3403 version rather than the later dual-op-amp revision.
The SD-1 side of the pedal has its own lineage. Guitar World reports that Boss developed the SD-1 as an improved version of the OD-1 by adding a tone control and making a few tweaks to the circuit5. TONEHOME notes the SD-1 uses the same asymmetric overdrive circuit as the OD-16. So the two modes on the OG-1 are closely related circuits, with the tone control being the main functional difference between them.
Guitar Pedal X reported in March 2026 that the OG-1 and the PastFx RetiKlon were largely invitation only, with a tiny number possibly appearing on the All Things Strings! Reverb.com store targeted at Americans2. By July 2026 the same site reported that "you can also now get the OG-1 too (OD-1 + SD-1)"7.
PastFx states that USA customers can purchase the OG-1 direct for a short time, with tariffs covered by PastFx1. The pedal is a limited run, so availability is not guaranteed to last.
The controls and switches
The OG-1's control set covers both modes plus several modifications PastFx added on top of the original circuits21.
| Control | What it does |
|---|---|
| Level | Sets output volume2 |
| Gain | Sets the amount of overdrive2 |
| Mode (OD / SD) | Switches between OD-1 and SD-1 circuits2 |
| Tone | Tone control, only active in SD mode1 |
| Presence pushbutton | Press in for additional high frequencies1 |
| SYM pushbutton | Press for symmetrical clipping; default is asymmetrical1 |
| 3-way Bass switch | Middle is stock, up is bass boost, down is bass cut1 |
The clipping behavior is worth understanding. By default the pedal clips asymmetrically, which is how both the original OD-1 and SD-1 circuits work1. Pressing the SYM pushbutton switches to symmetrical clipping, giving a second clipping character without opening the box. There is also an internal LED brightness control1.
The tone control's behavior follows the history of the two circuits: since the original OD-1 had no tone control at all, the Tone knob only works when the pedal is in SD mode1.
Power: 9V, with a big current gap between modes
The OG-1 runs on 9V DC through a 2.1mm Boss style negative tip jack, the same connector arrangement as a standard Boss pedal1. The notable spec is the current draw, which differs between the two modes:
Guitar Pedal X lists the pedal's power as 9V DC at 80mA2. If you power a board from a supply with limited current per output, size your allocation for the higher of the two mode figures rather than the lower one.
The 80mA SD mode draw is modest by digital pedal standards but well above a typical analog overdrive. Check your power supply's per-output capacity before daisy chaining the OG-1 with several other pedals.
Videos
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Questions
Is the PastFx OG-1 true bypass?
Yes. PastFx lists true bypass switching as one of the OG-1's features on its product page. The related Analog Man Colby OG-1 manual also specifies true bypass switching for that circuit.
What chip does the PastFx OG-1 use?
It uses a 14-pin 3403 IC, the same type of op-amp as the early Boss OD-1. Guitar Pedal X notes that this original Boss OD-1 14-pin chip is nearly unobtainable now, which is part of why the pedal is a limited run.
Does the tone control work in OD mode on the PastFx OG-1?
No. PastFx states that the tone control is only active in SD mode. In OD mode the pedal behaves like the original OD-1, which had no tone control at all.
What does the SYM button do on the PastFx OG-1?
The OG-1 clips asymmetrically by default, like the original OD-1 and SD-1 circuits. Pressing the SYM pushbutton switches the clipping to symmetrical, which changes the character of the overdrive.
How much current does the PastFx OG-1 draw?
PastFx lists approximately 10mA in OD mode and approximately 80mA in SD mode, both on 9V DC. The SD-1 mode draws roughly eight times the current of OD mode, so plan power supply headroom accordingly.
Can US customers buy the PastFx OG-1 directly?
For a short time, yes. PastFx states that USA customers can purchase direct, with tariffs covered by PastFx. The pedal was originally made to reward PastFx V.I.P. customers and was largely invitation only.
Sources (7)
- OG-1 Overdrive, PastFx, 2026
- Guitar Pedal X, Guitar Pedal X, 2026-03-04
- TONEHOME, TONEHOME
- Parhelion Vintage Overdrive / BOSS® OD-1 Overdrive, Aion FX, 2021-03-19
- Boss SD-1 Super Overdrive: what makes it a classic pedal, Guitar World, 2023-01-16
- TONEHOME, TONEHOME
- Guitar Pedal X, Guitar Pedal X, 2026-07-24
