125B · 3 knobs
Svenson Preamp
Based on the Benson Preamp· 3 other boards clone it
- Category
- Overdrive· Preamp overdrive/boost/fuzz
- Controls
- Drive · Treble · Bass
- Difficulty
- Intermediate (Requires Biasing
- Price
- €9.90out of stock
Heads up Builders widely report inconsistent quality from PCB Guitar Mania boards, and whether a given board works is a gamble. Read recent forum reports before ordering.
From the vendor
Project overview
This JFET preamp overdrive/distortion/fuzz is a Benson Chimera 30 Watt amplifier inside a box that has it all. It delivers a clean boost, soulful-bluesy overdrive, and even fuzz and distortion; all this versatility reached effortlessly.
Introduction
The Svenson Preamp is a circuit that captures the Chimera amplifier soul by substituting vacuum tubes for JFET transistors, like we have seen in many other preamps in a box or in Wampler Plexi.
This circuit is a jack of all trades, so better be ready to have all in one pedal: this circuit adds thickness to your tone and gives a blues drive-like sound without going to metal. Enriches your sound by incorporating harmonics and a very musical EQ into your signal chain. Delivers rusty overdrive/distortion waves while maintaining all your guitar’s original character. All of this, with the ability to dial effortless in the exact feature you want!
Controls
• Drive
• Treble
• Volume
• Bass
For further analysis on this circuit take a look at this thread on Free Stomp Boxes Forum.
For any technical questions regarding this build don’t forget to check out our Facebook Group and our forum at Free Stomp Boxes.
Svenson Preamp – Building Docs
Svenson Preamp – Drilling Template
Schematic
The schematic is in the vendor's build document, page 5. Open the build document. No KiCad fragment has been drawn for this circuit yet.
Parts list 37 rows
Report a wrong parse| Ref | Value | Normalized | Type | Notes |
|---|---|---|---|---|
| Resistors 14 | ||||
| R1 | 1m | 1M | ||
| R2 | 220k | 220k | ||
| R3 | 1m | 1M | ||
| R4 | 1k | 1k | ||
| R5 | 470k | 470k | ||
| R6 | 10k | 10k | ||
| R7 | 470k | 470k | ||
| R8 | 1k | 1k | ||
| R9 | 10k | 10k | ||
| R10 | 100k | 100k | ||
| R11 | 1k | 1k | ||
| R12 | 10k | 10k | ||
| R13 | 47k | 47k | ||
| R14 | 4k7 | 4.7k | ||
| Capacitors 12 | ||||
| C1 | 100n | 100n | ||
| C2 | 22n | 22n | ||
| C3 | 250p | 250p | ||
| C4 | 470p | 470p | ||
| C6 | 22n | 22n | ||
| C8 | 22n | 22n | ||
| C9 | 22n | 22n | ||
| C10 | 2n2 | 2.2n | ||
| C12 | 100n | 100n | ||
| C5 | 10u | 10u | ||
| C7 | 10u | 10u | ||
| C11 | 100u | 100u | ||
| Diodes 1 | ||||
| D0 | 1n5817 | 1N5817 | ||
| Transistors 3 | ||||
| Q1 | J201 | J201 | ||
| Q2 | J201 | J201 | ||
| Q3 | J201 | J201 | ||
| Potentiometers 3 | ||||
| DRIVE | 1MA | A1M | Potentiometer | |
| TREBLE | 250KA | A250k | Potentiometer | |
| BASS | 1MB | B1M | Potentiometer | |
| Trimmers 3 | ||||
| TRIM1 | 50K | 50k | Trimmer | |
| TRIM2 | 50K | 50k | Trimmer | |
| TRIM3 | 50K | 50k | Trimmer | |
| Jacks & sockets 1 | ||||
| J201 | Q1 | Q1 | ||
Other boards based on the Benson Preamp
- Chimera PreAmp Fuzz Dog · 1590B · £42.00
- Svenson Preamp SMD PCB Guitar Mania · 125B · €19.90
- Son of Ben Preamp PedalPCB · 125B · $8.00