Guitar Preamplifier Design
0:30
Considering schematic tools.
Analyzing the schematic.
Current schematic blocks
| Block | Function | Main parts |
|---|---|---|
| Input network | Guitar input, grid leak, stopper, coupling into first tube stage | 12AU7 first triode section |
| First gain stage | Initial voltage amplification | 12AU7 |
| Vox tone stack | Classic AC30-style EQ after stage 1 | treble/bass cut network using resistors and capacitors |
| Second gain / recovery stage | Recovers loss from tone stack and adds drive | 12AT7 |
| Output stage / driver | Sends preamp signal onward to the power amp or next section | remaining 12AT7 or remaining 12AU7, depending on final topology |
| B+ supply feed | High-voltage rail feeding tube plates through dropping/filter nodes | AC30-style preamp B+ ladder |
| Heater supply | Tube filament power | 6.3 V heater rail for 12AU7 and 12AT7 |
Main power connectionsDiagram
Diagram
Practical connection summary
| From | To | Purpose |
|---|---|---|
| Guitar input jack | 12AU7 first grid through input network | First amplification |
| 12AU7 first plate output | Vox tone stack input through coupling capacitor | EQ shaping |
| Tone stack output | 12AT7 grid | Gain recovery after insertion loss |
| 12AT7 plate output | Output coupling capacitor | Send signal to next stage |
| B+ rail | Plate resistors of each triode stage | Tube high-voltage supply |
| Heater rail | Filament pins of 12AU7 and 12AT7 | Tube heating |
Reviews
Polish Tube Amplifier with PreAmp
Properties
Properties describe core aspects of the project.
Pricing & Availability
Distributor | Qty 1 |
|---|
Controls
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