Distortion (Distortion with switchable Overdrive mode and sweepable Contour)
The Marshall JH-1 Jackhammer is an analog distortion with switchable Overdrive mode and sweepable Contour pedal based on the TL072 op-amp gain stages with LED and 1N4148 diode clipping; sweepable Valvestate-derived Contour mid-scoop network, with Gain, Volume, Bass, Treble, Contour, Contour Frequency (six controls on four shafts, three dual-concentric) controls.
| Category | Distortion (Distortion with switchable Overdrive mode and sweepable Contour) |
| Circuit / based on | TL072 op-amp gain stages with LED and 1N4148 diode clipping; sweepable Valvestate-derived Contour mid-scoop network |
| Signal | Analog |
| Controls | Gain, Volume, Bass, Treble, Contour, Contour Frequency (six controls on four shafts, three dual-concentric) |
| Switches | Mode select: O/D (overdrive) / DIST (distortion); On/Off switch |
| Footswitches | 1 |
| Bypass | Passive bypass |
| I/O | 1 x 1/4" jack input, 1 x 1/4" jack output, 9V DC input; input impedance >1 MOhm, output load impedance <20 kOhm |
| Power | 9V DC centre-negative regulated, or 9V PP3 battery |
| Power draw | 13 mA |
| Battery power | Yes |
| Dimensions | 120 x 65 x 55 mm |
| Weight | 510 g |
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