Marshall Amplification Rear panel 1959RR front panel features, 1959RR rear panel features

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Front panel - Randy’s preferred settings shown

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Rear panel

1959RR front panel features

 

 

1. POWER SWITCH

The change is very simple but effective and involves ‘cascading’ (feeding the

This is the On/Off switch for mains power to the amplifier. It will light up when

output of the first stage into the input of the second stage) the two halves of

your amplifier is receiving the correct mains power and is switched on. It will not

valve 1. Traditionally, each half would serve as input buffer/first gain stage for the

be lit when the amplifier is switched off and/or is not receiving mains power.

two channels, i.e. one half for channel 1 and the other for channel 2, from there

Note: Please ensure the amplifier is switched off and unplugged from the mains

they would separately feed the respective signals to the next stage which would

mix them, further amplify them and feed them to the tone stack.

electricity supply whenever it is moved.

Cascading valve 1 results in the guitar signal being increased by around 36dB or

2. STANDBY SWITCH

60 times, much larger than it would normally be at this point in the circuit.

The Standby Switch is used in conjunction with the Power Switch (item 1) to ‘warm

Subsequent stages then try to amplify this larger signal by similar amounts and

up’ the amplifier before use and to prolong the life of the output valves. When

quickly run out of headroom causing the waveform to distort severely. The two

powering up the amplifier always engage the Power Switch first, leaving the

channel volumes still remain functional after the modification but adopt different

Standby switch on ‘Standby’. This allows the application of the voltage required

roles for their affect on the tone, allowing control of the extra gain and volume.

to heat the valves to their correct operating temperature. After approximately two

Plugging into channel 2 routes the guitar signal through the whole cascade circuit

minutes the valves will have reached the correct operating temperature and the

while plugging into channel 1 allows you to bypass the cascade and use the amp

Standby Switch can be engaged. In order to prolong valve life, the Standby

in its standard format where ‘Volume 1’ will function as it normally would.

Switch alone should also be used to turn the amplifier on and off during breaks in

Standard Channel 2 format is sacrificed due to the modification.

a performance. Also, when switching off, always disengage the Standby Switch

7. VOLUME I

prior to the main Power Switch.

Note: The following four controls - PRESENCE (4), BASS (5), MIDDLE (6) &

This controls the overall output level of Channel I, turning it clockwise increases the

volume. This channel is voiced for a higher treble response. In full cascade mode,

TREBLE (7) - are all shared, meaning that they all work on both Channel I and

this controls the amount of signal amplified by the second half of valve 1, thereby

Channel II. The Treble, Middle and Bass controls are highly interactive and

acting as a crude master volume for the whole cascade circuit and can also be

altering one control can change the way the other two behave. For this reason,

thought of as a further gain control for the boosted signal to the subsequent

experimentation is recommended.

stages of the preamp. In standard mode i.e. guitar plugged into channel 1, it

Randy’s preferred settings are shown on the panel above.

functions just like a normal unmodified 1959 Super Lead volume control.

This control operates in the 1959RR’s power section and adds high frequencies to

Full cascade mode. This controls the amount of signal amplified by the first half of

3. PRESENCE CONTROL

8. VOLUME II

your sound by altering the power amplifier’s negative feedback. Turning this

valve 1 that is fed to the second half, thereby acting as a gain control for the

control clockwise adds more edge and ‘sparkle’ to your sound, making it crisper

cascade circuit itself.

and more cutting.

9. HIGH SENSITIVITY INPUT FOR CHANNEL

4. BASS CONTROL

This is the ‘high sensitivity’ guitar input for Channel I - the brighter of the two

This adjusts the bottom end, turning it clockwise increases the amount of low

channels - and is the most commonly used input on standard unmodified models.

frequencies in the sound.

Always use a high quality screened guitar lead. NOTE - Plugging into this input

5. MIDDLE CONTROL

bypasses the cascade and the amp functions in standard format.

This adjusts the level of those all-important mid-range frequencies. Turning it

10. LOW SENSITIVITY INPUT FOR CHANNEL

clockwise increases the mids and fattens your sound, giving it more punch.

This is the ‘low sensitivity’ guitar input for Channel I. It is 6dB lower (half) than the

Turning it anticlockwise reduces the mids.

‘high sensitivity’ input and results in less gain capability which may be required for

6. TREBLE CONTROL

guitars with very hot output pickups or active circuitry onboard. NOTE - Plugging

into this input also bypasses the cascade and the amp functions in standard format.

This adjusts the top-end. Turning it clockwise increases the amount of high

11. HIGH SENSITIVITY INPUT FOR CHANNEL II

frequencies (treble) present in the sound, making your tone brighter.

Tone/Tech talk - The modified Valve 1 stage

Plugging into this input enables the full cascade.

Unlike a standard Marshall 1959 Super Lead amplifier your Randy Rhoads

12. LOW SENSITIVITY INPUT FOR CHANNEL II

model contains a modification that increases gain and therefore extra distortion

Plugging into this input enables the full cascade. It is 6dB lower (half) than the

within the circuit. This modification ‘hot rods’ the amplifier making it easier to push

‘high sensitivity’ input and results in less gain capability which may be required for

it into the saturation levels necessary for the sound that Randy needed for his

guitars with very hot output pickups or active circuitry onboard.

musical station.

 

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1959RR rear panel features

 

 

 

1. LOUDSPEAKER OUTPUTS

WARNING! ALWAYS ensure that this rotary selector is set to the correct mains

WARNING! Never use the amplifier without a load attached!

voltage applicable for the country where the 1959RR is being used. If you do not

There are two parallel loudspeaker output jacks provided for connection to

know, consult your authorised Marshall dealer. Adjusting the selector from

230V/220V to 120V/110V/100V or vice-versa will require the mains fuse

speaker extension cabinet(s). Please always ensure that the amplifier's output

(item 5) to be changed to the correct value as detailed on the rear panel.

impedance selector is set correctly (see item 2) and ALWAYS ensure you use

4. MAINS INPUT

 

good quality speaker (unshielded) cables. NEVER use guitar (shielded) cables.

 

Always use a non-screened Marshall approved speaker lead when connecting an

Your amp is provided with a detachable mains (power) lead, which is connected

here. The specific mains input voltage rating that your amplifier has been built for

extension cabinet.

is indicated on the back panel. Before connecting for the first time, please ensure

2. OUTPUT IMPEDANCE SELECTOR

that your amplifier is compatible with your electricity supply. If you have any

doubt, please get advice from a qualified technician. Your Marshall dealer will

Matches the amplifier’s output to the load (speaker) impedance.

help you in this respect.

Your 1959RR should be completely powered down before the Output Impedance

5. MAINS FUSE

 

Selector is turned.

The correct value of mains fuse is specified on the rear panel of the amplifier.

As is the case with any Marshall all-valve amplifier it is imperative that: a) the

NEVER attempt to bypass the fuse or fit one of the incorrect value.

amplifier is connected to a load whilst in operation and b) the impedance selected

6. H.T. FUSE

 

on the amplifier matches the total impedance of the extension speaker cabinet(s)

The correct value of this H.T. fuse is specified on the rear panel of the amplifier.

being used.

NEVER attempt to bypass the fuse or fit one of the incorrect value.

1x16 Ohm cabinet - Selector on 16 Ohm - Use either speaker output

Technical Specification

2x16 Ohm cabinets - Selector on 8 Ohm - Use both outputs

Power Output - 100W RMS

1x8 Ohm cabinet - Selector on 8 Ohm - Use either output

Weight - 21.4 kg

 

2x8 Ohm cabinets - Selector on 4 Ohm - Use both outputs

Size - 740mm x 270mm x 210mm

1x4 Ohm cabinet - Selector on 4 Ohm - Use either output

 

 

 

WARNING! Do NOT use any other combination of cabinets and/or

* EUROPE ONLY

 

- Note: This equipment has been tested and

 

impedances. Doing so may result in damage to the amplifier! An extension

found to comply with the requirements of the EMC Directive

speaker cabinet with an impedance of less than 4 Ohms, or two extension

(Environments E1, E2 and E3 EN 55103-1/2) and the Low Voltage

cabinets of 4 Ohms or less should NOT be used with this amplifier.

Directive in the E.U.

 

Failure to comply with any of the points raised in this section will result in damage

* EUROPE ONLY - Note: The Peak Inrush

current for the 1959RR is 38 amps.

to the amplifier.

 

 

 

Matches3. MAINStheSELECTORamplifier’s mains transformer to the incoming mains voltage.

Your 1959RR should always be completely powered down before the mains selector is turned.

ENGLISH

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Contents Page Dear Randy fan From Jim MarshallRandy Rhoads Tribute to a Timeless Talent Paul Gilbert 1959RR rear panel features Rear panel 1959RR front panel features