The Jetter Gain Stage Red is an overdrive pedal from Jetter Gear, sitting in the same family as the maker's other drive circuits such as the JetDrive and Red Square. Its main claim to attention today is its place in Jetter's history: MusicRadar's review of the Red Shift states that "The Red Shift is developed from the earlier Gain Stage Red pedal," making the Red the circuit behind one of Jetter's current overdrives1. Like all of the company's drives, it belongs to the broader world of overdrive pedals, where it sits apart from the distortion and fuzz categories by keeping an amp-like clipped character.
The circuit and its DIY layout
Much of what is documented about the Gain Stage Red in public comes from the DIY community. The Guitar FX Layouts blog posted a vero (stripboard) layout for the circuit on 30 January 2012, tagged simply as an overdrive2. Stripboard layouts let players build the circuit themselves on perforated copper board, and the comment thread under this one became a working record of how the pedal behaves on a breadboard-style build.
One correction mattered enough to be spelled out. The original layout had the Drive pot wired backwards, and the builder noted, "I needed to swap (Drive 1) and (Drive 3) to get clockwise gain increase," with the layout corrected on 10 February 20122.
If you build from the original January 2012 layout, the Drive pot's outer lugs need swapping so that turning clockwise increases gain. The corrected layout dates from 10 February 20122.
Another builder, Benno, confirmed the fix the same month: "Otherwise works like a charm. Sounds tops!!"2.
Op-amp choices builders found
Because the layout exposes the op-amp position, builders tried different chips in the same circuit. Ross's audition, posted 11 February 2013, compared three2:
| Op-amp | What the builder heard |
|---|---|
| OP275 | "Super clear and articulate," his favorite2 |
| LM833 | "Dark, but clear enough to play chords with"2 |
| LM358 | "Muddy, almost fuzzy quality. The clear loser."2 |
For anyone building or modifying the circuit, that makes the OP275 the chip builders gravitated to, with the LM833 as a darker but usable alternative2.
Bass use
The same thread records the Gain Stage Red working beyond guitar. Ross reported: "WOW. This one's actually a killer bass drive. I used 1N4148s for D1 and D2, a 1N34 for D3, and 2N7000s for Q1+2."2. That is a specific parts substitution, not a stock setting, so a player wanting a bass version of the circuit would follow that recipe: silicon 1N4148 diodes in the D1 and D2 positions, a germanium 1N34 at D3, and 2N7000 transistors for Q1 and Q2. Players browsing bass pedals more broadly will find dedicated bass circuits elsewhere on the site.
The family: Red Shift and Gain Stage Green
The Gain Stage Red's legacy runs through the Red Shift, which MusicRadar identifies as its descendant1. Jetter's overdrive range has also grown around it: Premier Guitar noted that "Jetter now offers six overdrive pedals, catering to a wide variety of distortion tastes," including the Gain Stage Green and the GS3 Dual Overdrive3. Of the Green, Premier Guitar's reviewer found that "the Gain Stage Green does lean toward the British side of the tonal spectrum," and that with the gain set between off and 9 o'clock, "the Green operates almost as a clean boost, with just a hint of 'give'"3. Players wanting a cleaner foundation under any of these drives can look at boost pedals, while Jetter's later Pedal X took a different approach to gain altogether.
Videos
ProGuitarShopDemos
bjeter
bjeter
Questions
What is the Jetter Gain Stage Red?
The Gain Stage Red is an overdrive pedal from Jetter Gear. MusicRadar describes it as the earlier pedal from which Jetter developed the Red Shift, its later overdrive. A stripboard layout for the circuit was posted on the Guitar FX Layouts blog in January 2012, where builders worked through the circuit and shared their results.
Which op-amp did builders prefer in the Gain Stage Red?
In an op-amp audition on the Guitar FX Layouts blog, builder Ross found the OP275 super clear and articulate and called it his favorite. The LM833 was dark but clear enough to play chords with, while the LM358 was muddy with an almost fuzzy quality, which he called the clear loser.
Can the Gain Stage Red be used for bass?
Yes, according to a builder on the Guitar FX Layouts blog. Ross reported that with 1N4148 diodes for D1 and D2, a 1N34 for D3, and 2N7000 transistors for Q1 and Q2, the circuit worked as what he called a killer bass drive.
What is the Jetter Gain Stage Green?
The Gain Stage Green is another overdrive in Jetter's range. Premier Guitar's reviewer found it leans toward the British side of the tonal spectrum, and noted that with the gain set between off and 9 o'clock it operates almost as a clean boost, with just a hint of give.
Why do the Drive lugs need swapping on the Gain Stage Red layout?
On the stripboard layout posted at Guitar FX Layouts, the builder needed to swap lugs 1 and 3 on the Drive pot to get clockwise gain increase. The layout was corrected, and another builder confirmed that after the swap the pedal worked correctly and sounded good.
How does the Gain Stage Red relate to the Red Shift?
The Red Shift is Jetter's later overdrive, and MusicRadar's review states it was developed from the earlier Gain Stage Red pedal. Players interested in the Red Shift's voicing can read its own page for the full picture of how the circuit evolved.
Sources (3)
- Jetter Red Shift review, MusicRadar, 2011-04-21
- Guitar FX Layouts: Jetter Gain Stage Red, Guitar FX Layouts (tagboardeffects.blogspot.com), 2012-01-30
- Jetter Gear Pedal Reviews: Gain Stage Green & GS3 Dual, Premier Guitar, 2009-09-18
