User manual MARSHALL JVM410C COMBO

[. . . ] ENGLISH From Jim Marshall I would like to thank you personally for selecting one of our new `JVM' amplifiers. Since I started Marshall Amplification in 1962 I have witnessed some incredible breakthroughs and advances in amplifier design technology, such as master volume amps, channel switching, reverb, effects loops, MIDI technology, speaker emulation and digital effects processing, to name just a few. These may all seem commonplace features nowadays but that certainly wasn't always the case. However, the same values that were present in the first Marshalls are still very much here today: meticulous workmanship, reliability, stylish looks and, above all, great Marshall tone. [. . . ] This is because the signal is being distorted after the tone stage, minimising the effectiveness of the Bass, Middle and Treble controls. CRUNCH CHANNEL At this point the JVM reverts to the more typical Marshall preamp circuit characteristic of `gain then tone'. ENGLISH CRUNCH GREEN MODE: This mode shares the preamp topology of the classic Marshall JTM45/1959 `Plexi' models (i. e. : gain + gain + tone) but with a bit more of gain than is found in the originals. CRUNCH ORANGE MODE: This mode is reminiscent of the Marshall JCM800 2203 amplifier, a staple of hard rock. PRESENCE, RESONANCE These controls are power amplifier controls and only have effect when playing through a speaker (not in silent recording). They affect how the power amplifier reacts to the connected speakers and how much control the amplifier has over them. Increasing the RESONANCE control emphasises the natural speakers resonance for an improved bass response. In the same way, increasing the PRESENCE control emphasises the speaker's high frequencies which will be heard as an improved high frequency response which adds presence to the sound. 6 Presence and Resonance constitute a powerful power amplifier equaliser, allowing responses from a `^' shape when they are fully off, which is felt as a mid boost, to a `v' shape when they are turned clockwise, which is felt as a scooped sound. Again, the effectiveness of these controls is highly dependant on the kind of connected speakers. Care has to be taken to avoid over excursion of the speaker cones in high resonance settings. FX LOOP This is a programmable FX loop which features a MIX control on the rear panel and it is located after the pre-amp, right before the reverb and serial loop circuits. Please refer to the Serial / Parallel Loop description later on in the handbook for its operation. FOOTSWITCH / MIDI PROGRAM This switch has a dual function: Pressing it once we enter the FOOTSWITCH PROGRAM mode. Footswitch program and use The JVM range features a new type of fully configurable footswitch. Connection to the amplifier requires a standard mono 1/4" jack to jack cable. Any guitar lead will work and practically there should be no limit in its length. When the front panel FOOTSWITCH / MIDI PROGRAM switch is off, the footswitch operates in safe mode and executes the commands the moment the switch is pressed down. If you enter the FOOTSWTICH PROGRAM mode (LED red) you will be able to program the footswitch but nevertheless the footswitch and the amplifier will remain fully operational with the only difference that the commands will be executed when releasing the footswitches, as opposed to the normal mode. Each of the individual footswitches has 2 modes of operation: preset store and switch store. In preset store mode, any of the footswitches can be configured to store the current amplifier status. The current channel, master, FX and reverb status will be stored and recalled when the respective footswitch is pressed. To store the current status simply: Set the amplifier to FOOTSWITCH PROGRAM mode (red light ON). The FX footswitch LED will flicker a couple of times indicating that the preset has been stored. [. . . ] This is achieved as follows: Unplug the footswitch at any of the cable sides. Release the switch and the footswitch will synchronise with the amplifier. The factory default is as follows: FSW #1: Clean Mode FSW #2: Crunch Mode FSW #3: OD1 Mode FSW #4: OD2 Mode FSW #5: Master FSW #6: Reverb Hints Hint 1: It is possible to use different modes in the same channel with different volumes to avoid imbalance which can be especially interesting in the Clean channel. To do this simply create 2 presets in the footswitch assigning MASTER 1 or MASTER 2 to any of the modes. [. . . ]