Marshall Amplification JH-1 User manual

JH-1 Jackhammer
Jackhammer Suggested Settings
Owners Manual
CLASSIC CRUNCH (Amp: Clean)
CLASSIC DRIVE (Amp: Slightly Overdriven)
ULTRA CRUNCH (Amp: Clean)
ULTRA LEAD (Amp: Clean)
Whilst the information contained herein is correct at the time of
publication, due to our policy of constant improvement and
development, Marshall Amplification plc reserve the right to alter
specifications without prior notice.
7 / 05
Marshall Amplification plc
Denbigh Road, Bletchley, Milton Keynes,
MK1 1DQ, England.
Tel : [phone] Fax : [phone]
www.marshallamps.com

WARNING!
IMPORTANT Precautions
Refer all servicing to qualified service personnel. Servicing is
required when the apparatus has been damaged in any way,
such as liquid has been spilled or objects have fallen into the
apparatus, the apparatus has been exposed to rain or moisture,
does not operate normally, or has been dropped.
WARNING
Do not expose the apparatus to rain or moisture. Do not expose
the apparatus to dripping or splashing. No objects filled with
liquids should be placed on or near the apparatus. Do not use
this apparatus near water.
Clean only with dry cloth.
Changes or modifications not expressly approved by Marshall
Amplification plc could void the user’s authority to operate the
equipment.
Heed all warnings.
Follow all instructions.
Keep these instructions.
European Product Only
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From The Chairman
I would like to personally thank you for
selecting one of our effects pedals.
For over 40 years the Marshall name has been synonymous with the
greatest guitar tones in music. We have worked hand in hand with
guitarists from all levels throughout the world to maintain and
improve that special ingredient, ‘The Marshall Sound.’
Our range of effects pedals gives the opportunity to augment the
classic Marshall tone to add Marshall character to a guitar set-up.
All our pedals are made with the same utmost attention to quality, in
both materials and manufacture as our world renowned amplifiers,
cabinets and combos, in order to provide you with optimum
reliability and tone.
I would like to wish you every success with all of your musical
endeavours and also your new Marshall effects pedal, which I am
sure you will find a pleasure to play for many years to come.
Yours Sincerely,
1
ENGLISH

2
Introduction
Since we 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 our valve amps by
cranking it up to full volume. As time went by our Master Volume
heads allowed the generation of more extreme levels of distortion as
the pre-amps valves were driven into overdrive. Our 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. It contains our 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 aggresion and gain than any other
Marshall pedal, we never forget our heritage. The sounds contained are
always natural and realistic, like a super high-gain valve head pushed
to the max.
The Jackhammer features two modes; Overdrive and Distortion.
Overdrive delivers an open crunch for that classic Marshall roar,
whereas Distortion gives you a smooth and singing compressed high
gain tone.
The Jackhammer features a passive bypass for the main signal path, to
ensure complete tonal integrity and has a quality of tone matched only
by its versatility.
Here follows a complete run down of the Jackhammer’s features for
your information. We have also enclosed a number of suggested
settings to help guide you. It should be remembered that these are
only suggested settings and you should experiment as much as
possible.
If you take the time to explore the many different overdrive and
distortion characters of the Jackhammer, you won’t be disappointed.
Features
1. Jack Socket
This is the output of the Jackhammer and is for connection to the
amplifier or to another effects pedal.
2. Mode
Allows for selection of the Jackhammer’s two modes; Overdrive and
Distortion. Overdrive gives you traditional Marshall open roar,
similar to JCM 800 style Master Volume models with more bite and
dynamics. Distortion Mode delivers a more saturated high gain
compressed tone, similar to the high gain channels on JCM 2000
models.
3. Gain
This increases the amount of distortion, taking you from vintage
Always use good quality shielded leads.
Always use 9V regulated DC supply with centre negative.
Although it may seem obvious the first action in achieving a good
effected sound (be it duration / compression etc.) is to find the
perfect bypassed sound. This will then allow the correct level to be
set with the effect unit to allow a cut or boost in volume and a
realistic tone.
On clean channels it is advisable to set the gain (or volume) to a
setting of no less than one quarter maximum so as not to get
unrealistic results due to any volume dependent tonal shaping on
the amplifier preamp.
Setting Up
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breakup, ideal for big crunchy chords, sweet singing blues and classic
rock on Crunch mode; and from powerful overdrive to full on high gain
distortion and compressed super saturation on the Lead mode.
4. Volume
Adjusts the volume of the Jackhammer, allowing you to set the pedal
for a boost or cut in volume when in operation, should you so wish.
5. DC Input
For input of a 9V DC adaptor (as detailed previously) should you not
wish to use batteries
6. LED
Indicates when the Jackhammer is in operation.
7. Treble
Adjusts the Treble frequencies in your tone.
8. Bass
Adjusts the bass frequencies of your tone.
9. Contour Freq.
By adjusting the Contour Freq. you can govern exactly which
frequencies the Contour control (item 9) will scoop. With the Contour
Freq. set at 12 o’clock the Contour acts like a traditional Marshall
Contour control. Turning the Contour Freq. anti-clockwise cuts lower
mids and bass from your tone, while turning the Contour Freq.
clockwise will cut upper mids and treble.
10. Contour
The Jackhammer features a stunning Contour control, modelled on the
acclaimed Contour circuitry found on our Valvestate models. This
allows you to ‘scoop’ certain frequencies from your tone. This item
controls the amount of scoop in your tone. Turning clockwise will
scoop out more mid. When full counter-clockwise the Contour section,
including the Contour Frequency control, is bypassed.
11. Jack Socket
This is the input jack, for connection from your guitar or from another
effects pedal if you are linking pedals together.
12. Foot Switch
For switching the Jackhammer on and off.
WHAT IF
NO
OUTPUT
SOUND TOO
TREBLY OR
FIZZY
UNUSUAL
HUM
BASS
FEEDBACK
SOUND TOO
MUSHY OR
BASSY
UNUSUAL
FEEDBACK
INDICATOR
LED NOT
ON
NOISE IN
BYPASS
CHECK BATTERY CHECK LEADS CHECK PEDAL CONTROLS DC INLET CHECK AMP CONTROLS
CHECK GUITAR
REDUCE
TREBLE
REDUCE
TREBLE
INPUT
LEAD
Trouble Shooting
33
3
3
3
3
3
3333
3
333
3
3
33
333
MOVE AWAY
FROM AMP
PICKUPS
MAY BE
VIBRATING

76
ESPAÑOL
Battery Replacement
1. To replace the battery, open the
easily accessed coin screw
battery cover plate by loosening
screw as shown, then
disconnect the battery connector
lead.
2. Use PP3 or equivalent battery
(for improved battery life use
alkaline type)
3. Always ensure that the battery is
removed when the pedal is not
in use for long periods.
4. Dispose of old battery in a safe
place.
Technical Specification
Power: 9V DC Centre Negative Regulated
Current Draw: 13mA
Controls: Overdrive & Distortion Mode, Gain, Volume, Bass, Treble,
Contour & Contour Frequency controls
Switches: On/Off Switch
Indicators: On/Off LED
Jacks: Input/Output ‘Jacksockets’
Input Impedance: 1M Ω
Output Load Impedance: < 20k Ω
Dimensions: 120mm x 65mm x 55mm
Weight: 510 grammes
Unas palabras
del Presidente
Quiero agradecerte personalmente el haber elegido uno de nuestros
pedales de efectos.
Desde hace más de 40 años el nombre de Marshall es sinónimo del
mejor sonido de guitarra. Hemos trabajado mano a mano con
guitarristas de todos los niveles y de todas partes del mundo para
mantener y mejorar este ingrediente especial: “El sonido Marshall”.
Nuestra gama de pedales de efectos te da la oportunidad de
aumentar el clásico tono de Marshall o añadir personalidad a
cualquier equipo de guitarra. Están fabricados prestando tanta
atención a la calidad de los materiales como el resto de la gama de
amplificadores y combos Marshall, para ofrecerte gran fiabilidad y
tono.
Quiero desearte grandes éxitos en todas tus empresas musicales y
con tu nuevo pedal de efectos Marshall, que estoy seguro te
resultará un placer utilizar durante muchos años.
Sinceramente,