The Marshall Jackhammer JH-1 is built in a tough roadworthy light gray enclosure which is shared across the whole Marshall line of stomp-boxes. It has 1/4 inch input and output sockets, on/off switch with LED indicating "On" position. There are controls for "Mode", "Gain", "Volume", "Treble", "Bass", "Contour" and "Contour Frequency". The Marshall Jackhammer JH-1 can be powered via a 9 volt battery or a 9 volt adapter (not supplied).
The Marshall Jackhammer JH-1 is a dual mode stomp-box, it can operate either as an overdrive or as a distortion pedal. According to the manual the overdrive mode gets close to the character of a JCM800, while the distortion is close in voicing to the JCM2000 series Marshall amps.
Manufacturers Quote The Marshall JH-1 JACKHAMMER Guitar Effect Pedal, Ultragain Overdrive. Create your own truely awesome, extreme Marshall distortion tones.
The Marshall JH-1 JACKHAMMER delivers the extreme distortion effects you crave. Since Marshall began in 1962, the Marshall name has been synonymous with high quality distortion tones. Initially, the way to get classic Marshall distortion was to naturally overdrive one of their valve amps by cranking it up to full volume. As time went by the Marshall Master Volume heads allowed the generation of more extreme levels of distortion as the pre-amp valves were driven into overdrive. Marshall's first generation pedals simulated these various valve amp type distortions in convenient, cost effective stomp boxes. The Jackhammer is the next step on from previous Marshall distortion pedals. The JH1 pedal contains Marshall's most extreme distortion levels to date, combined with a Contour section that allows you to not only scoop out the mids, but also choose the frequencies at which the scoop occurs. This means that you can tailor your sound to your own individual requirements. Although the Jackhammer has more aggression and gain than any other Marshall pedal, thay never forget their heritage. The sounds contained are always natural and realistic, like a super high-gain valve head pushed to the max.
In Use
The Gain and Volume controls are stacked on top of each other, as are consequently the bass and treble controls, and the contour and contour frequency knobs. This makes the operation a little cumbersome at first but looking at the size of the unit it is amazing that Marshall have managed to put so much tonal control in a box of this size. The controls are little hard to get used to, due to their diminutive size, especially when a minor adjustment might need to be made in the middle of a show.
The build quality seemed tough and this enclosure is the same as the others from Marshall's line of pedals - metal enclosure with quality jacks. The review unit could not power from batteries but worked via power supply - a manufacturing defect that should not be a problem considering the pedal's warranty.
I was actually amazed how "Marshall" this small box sounded - right after plugging into it the Marshall character was instantly recognizable. The overdrive provides plenty of tonal options from blues to hard rock, while the distortion takes things further into metal territory. The overdrive works wonderfully for juicing up a tube amp - in this case my Marshall JCM900 and Marshall VS8100 amps benefited from the extra boost and sustain from the overdrive setting. The distortion mode also sounded great through an amp's clean channel and the contour allowed enough control that there was always enough flexibility to dial in a convincing sound. On certain amps the pedal on the distortion setting felt a bit bass heavy, but again - most of the time I managed to dial this out by using the amps' and pedals' eq control.
The Bottom Line
Overall the JH-1 is a very versatile unit and for those musicians looking for a distortion unit and an overdrive at the price of a single pedal this unit is a definite must!
Pros- Overdrive and Distortion in a Single Pedal
- Marshall sound
- Versatility
- Price
Cons- Small Control Knobs
- Could sound overly bassy on some amps
- Manufacturer Defect on review unit
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Marshall Jackhammer JH-1 Pedal
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