1590BB · 3 knobs
Valv-e-tizer
- Category
- Preamp / Amp-in-a-box
- Price
- €8.06in stock
From the vendor
A real 12AU7 / 12AT7 / 12AX7 dual-triode preamp stage in a 1590BB enclosure, powered by a CD40106-based voltage multiplier — from ultra-clean warmth to tube-driven distortion on a standard 9 V pedalboard supply. The Valv-e-tizer allows you to build a real tube pedal for your pedalboard. Based on the tube and part values chosen it can range from ultra-clean to heavy distortion. The circuit was inspired by Juansolo’s BoobTube design; credit for the original topology goes to him. Board V1.5 adds extra mounting holes to support the tube socket during tube insertion and removal. The intention is a board that can be used to try out most basic tube-amp circuits without the lethal hazard of working
Schematic
The schematic is in the vendor's build document. Open the build document. No KiCad fragment has been drawn for this circuit yet.
Parts list 42 rows
Report a wrong parseGot parts in a drawer? See what you can build with them.
| Ref | Value | Normalized | Type | Notes |
|---|---|---|---|---|
| Resistors 7 | ||||
| R1 | 2k7 | 2.7k | Metal film ¼ W. Charge pump oscillator frequency resistor. | |
| R2 | 100k | 100k | Optional V1B grid stopper. Fit for ultra-clean voicing; see voicing table. | |
| R4 | 1M | 1M | V1A grid-leak resistor to GND. | |
| R5 | 150k | 150k | V1A anode load resistor. | |
| R6 | 100k | 100k | V1B anode load resistor. | |
| R7 | 100k | 100k | V1B grid-leak resistor to GND. | |
| R8 | 2k2 | 2.2k | LED series current-limiting resistor. Test LED brightness with your specific LED first — a value between 1k5 and 3k3 is typical. | |
| Capacitors 18 | ||||
| C1 | 47 n | 47n | Box film (MKP/MKT), 80–100 V rating minimum . Multiplier chain and grid stopper caps. | |
| C2 | 47 n | 47n | Box film (MKP/MKT), 80–100 V rating minimum . Multiplier chain and grid stopper caps. | |
| C3 | 47 n | 47n | Box film (MKP/MKT), 80–100 V rating minimum . Multiplier chain and grid stopper caps. | |
| C4 | 47 n | 47n | Box film (MKP/MKT), 80–100 V rating minimum . Multiplier chain and grid stopper caps. | |
| C5 | 47 n | 47n | Box film (MKP/MKT), 80–100 V rating minimum . Multiplier chain and grid stopper caps. | |
| C6 | 47 n | 47n | Box film (MKP/MKT), 80–100 V rating minimum . Multiplier chain and grid stopper caps. | |
| C8 | 47 n | 47n | Box film (MKP/MKT), 80–100 V rating minimum . Multiplier chain and grid stopper caps. | |
| C10 | 47 n | 47n | Box film (MKP/MKT), 80–100 V rating minimum . Multiplier chain and grid stopper caps. | |
| C16 | 47 n | 47n | Box film (MKP/MKT), 80–100 V rating minimum . Multiplier chain and grid stopper caps. | |
| C7 | 1 n | 1n | Box film. Charge pump oscillator timing cap. | |
| C11 | 22 n | 22n | Box film. Input coupling cap. Some voicings use 100 n — see voicing table. | |
| C12 | 47 n | 47n | Box film. V1A anode / grid-stopper cap. Some voicings use 22 n or 10 n — see voicing table. | |
| C13 | 47 n | 47n | Box film. TONE control series cap. | |
| C15 | 150 n | 150n | Box film. V1A cathode bypass. Bypasses cathode above ≈ 1.3 kHz. Ultra-clean voicing only. | |
| C17 | 150 n | 150n | Box film. V1B cathode bypass. Active when R3 = 820 R. | |
| C9 | 220 µ | 220u | Electrolytic, rated ≥ 16 V. Power supply filter cap. | |
| C14 | 1 µ | 1u | Electrolytic. V1B output coupling cap. Empty (not fitted) in ultra-clean voicing — see voicing table. | |
| C18 | 1 µ | 1u | Electrolytic. Optional extra V1A cathode bypass for ultra-clean voicing. Empty in clean / distortion builds. | |
| Diodes 7 | ||||
| D1 | 1N4148 | 1N4148 | Fast signal diode. Voltage multiplier chain. Must be rated for repeated reverse voltage; 1N4148 is fine. | |
| D2 | 1N4148 | 1N4148 | Fast signal diode. Voltage multiplier chain. Must be rated for repeated reverse voltage; 1N4148 is fine. | |
| D3 | 1N4148 | 1N4148 | Fast signal diode. Voltage multiplier chain. Must be rated for repeated reverse voltage; 1N4148 is fine. | |
| D4 | 1N4148 | 1N4148 | Fast signal diode. Voltage multiplier chain. Must be rated for repeated reverse voltage; 1N4148 is fine. | |
| D5 | 1N4148 | 1N4148 | Fast signal diode. Voltage multiplier chain. Must be rated for repeated reverse voltage; 1N4148 is fine. | |
| D6 | 1N4148 | 1N4148 | Fast signal diode. Voltage multiplier chain. Must be rated for repeated reverse voltage; 1N4148 is fine. | |
| D7 | 1N4148 | 1N4148 | Fast signal diode. Voltage multiplier chain. Must be rated for repeated reverse voltage; 1N4148 is fine. | |
| ICs 2 | ||||
| IC1 | CD40106N | CD40106N | Hex Schmitt-trigger inverter, DIP-14. Drives voltage multiplier. HEF40106BP 74HC14 | |
| IC2 | uA7806 / 78M06 | UA7806 / 78M06 | 6 V positive linear voltage regulator, TO-92 or TO-220. Sets tube heater voltage. Or substitute a 6 V switching module. LM7806 78M06 | |
| Potentiometers 3 | ||||
| GAIN | B50k | B50k | 16 mm PCB-mount linear pot (B taper). Controls signal level between V1A and V1B stages. | |
| TONE | A100k | A100k | 16 mm PCB-mount log pot (A taper). Passive high-cut treble control after V1B. | |
| VOL | A100k | A100k | 16 mm PCB-mount log pot (A taper). Master output level. | |
| LEDs 1 | ||||
| LED | LED 3 mm | LED 3 MM | Super-bright 3 mm LED. Mounted from PCB underside through hole in Noval socket for internal glow effect. | |
| Jacks & sockets 1 | ||||
| S1 | Noval PCB socket | NOVAL PCB SOCKET | 9-pin Noval print socket. Ensure socket has a centre hole if using LED-glow-through mounting. Leave space between socket and PCB. | |
| Other 3 | ||||
| BIAS1 | 5k or 10k | 5K OR 10K | 6 mm cermet trimmer. Sets V1A quiescent operating point. Adjust for clean headroom or desired breakup. | |
| BIAS2 | 5k or 10k | 5K OR 10K | 6 mm cermet trimmer. Sets V1B quiescent operating point. Some voicings use 250 k — see voicing table. | |
| V1 | 12AU7 | 12AU7 | 9-pin Noval dual-triode. Ultra-clean and clean voicings use 12AU7 (ECC82); distortion voicing uses 12AT7 (ECC81). 12AX7 (ECC83) also fits for maximum gain. 12AU7 / ECC82 12AT7 / ECC81 12AX7 / ECC83 | |