The PastFx Preamp Crunch is a stand-alone recreation of the preamp section of the BOSS CE-1 Chorus Ensemble. PastFx says it came about after many requests to have the CE-1's bypass channel, the part of that pedal many players used on its own as a preamp and clean boost, available in a single enclosure, and calls it the most faithful recreation of the CE-1's preamp1. BOSS discontinued the CE-1 over 30 years ago, but the company notes it remains widely used by many players for its characterful preamp2.
Where it comes from
The BOSS CE-1 Chorus Ensemble is best known as a chorus pedal, but its bypass channel carries a preamp that players have long used on its own for lift and color. PastFx states that the Preamp Crunch is the only recreation of the CE-1's preamp with the correct internal voltages, the exact peak level LED indicator circuit, and a buffer circuit that can be added or removed as desired1. The pedal runs off the same bipolar voltages as the original CE-11.
Controls and the buffer switch
The original Preamp Crunch keeps things simple: one Level control and a normal/effect footswitch1.
| Control | What it does |
|---|---|
| Level | Sets the preamp level1 |
| Buffer switch | Adds or removes the built-in buffer circuit; only available when the effect is activated1 |
| Normal/effect footswitch | Engages or bypasses the effect1 |
The buffer switch matters because the original CE-1 could lose high frequencies at high input sensitivity. PastFx includes the buffer to remedy that, and leaves it to the player to add or remove3.
"On some amps it can almost sound like a fuzz, and on others a more traditional crunch sound! This is the same experience"
PastFx describes that range of character as the same experience as the original pedal: pushed hard with the Level control high, it can read as a light fuzz on some amps and a more traditional crunch on others1.
Power
The pedal operates off industry standard 9VDC negative tip, 2.1mm power, or a 9V battery1. PastFx notes it can draw up to approximately 55mA, so a power supply rated at 100mA minimum should be more than adequate; that draw is worth keeping in mind when sharing a daisy-chain supply1.
Preamp Crunch and Preamp Crunch Plus
PastFx also makes an expanded version, the Preamp Crunch Plus, described as an expansion of the Preamp Crunch Classic, which is the isolated preamp from the PastFx Chorus Ensemble in its own enclosure3.
| Preamp Crunch Classic | Preamp Crunch Plus | |
|---|---|---|
| Level control | Yes1 | Yes, determines crunch, overall tone, gain level and volume output3 |
| Master volume | No | Yes, compensates for higher gain settings or achieves unity gain at any point in the Level sweep3 |
| Pot Mod switch | No | Internal switch between two potentiometer values for the Level control, allowing the signal to clip and crunch earlier3 |
| Bypass | True Bypass1 | True Bypass or buffered operation, selectable via the on/off switch3 |
| Power | 9V DC or 9V battery, up to approximately 55mA1 | 9V center negative supply drawing 55mA, or 9V battery3 |
The Plus also comes in a new version with premium toggle switches3. With the Master Control set fully clockwise, the Plus operates with the same stock circuit as the Classic, so the extra control does not change the core voicing unless used3.
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Questions
Is the PastFx Preamp Crunch true bypass?
Yes. The manual for the Preamp Crunch lists it as true bypass. On the Preamp Crunch Plus, PastFx makes bypass selectable: the pedal can run true bypass or buffered operation, chosen via the on/off switch. The buffer itself is there to remedy high frequency loss some users experienced with the original BOSS CE-1 at high input sensitivity.
Can the PastFx Preamp Crunch run on a battery?
Yes. The manual says the pedal runs on a standard 9V DC pedal power supply or a 9V battery. Note that it can draw up to approximately 55mA, so a power supply rated at 100mA minimum is described as more than adequate. A 9V battery is also listed for the Preamp Crunch Plus.
What is the buffer switch on the Preamp Crunch for?
The built-in buffer switch adds or removes the pedal's buffer circuit. PastFx includes it to remedy the high frequency loss some users experienced with the BOSS CE-1 on high input sensitivity. On the original Preamp Crunch, the buffer switch is only available when the effect is activated.
What is the difference between the Preamp Crunch and the Preamp Crunch Plus?
The Plus is an expansion of the Preamp Crunch Classic. It adds a Master Control for setting overall volume, an internal Pot Mod switch that swaps between two potentiometer values for the Level Control so the signal can clip and crunch earlier, and selectable true bypass or buffered operation. With the Master Control fully clockwise, the Plus operates with the same stock circuit as the Classic.
What polarity and connector does the Preamp Crunch use?
The manual specifies an industry standard 9VDC negative tip, 2.1mm barrel connector, the same center negative arrangement used by most pedal power supplies. The pedal can also run from a 9V battery.
Sources (3)
- PastFx Chorus Ensemble Mini Manual final, PastFx, 2020-12
- BOSS - BP-1W | Booster/Preamp, BOSS (www.boss.info)
- Preamp Crunch Plus, pastfx.com, 2026
