The El Guapo (it uses EL-34 tubes) is a collaboration between Jackson Ampworks and one of the greatest blues guitarists of our time; Josh Smith. Josh approached us a few months ago asking if we had any interest in making a 100W Super Bass with a Super Lead voiced High Gain second channel. As it turns out, I was about to start working on a 100W Super Bass design so the timing was perfect for our collaboration on this amp.

CHANNEL 1

Channel 1 of the El Guapo has some of the richest and punchiest clean tones you’ve ever heard and is a dead ringer for the tones that you hear coming from Hendrix and guys like Doyle Bramhall II who famously have used Super Bass amps over the years. With the 100W power section (switchable down to 50W) Channel 1 of the El Guapo has an unbelievable level of clean headroom and will shake the walls of your house before it ever starts breaking up!

About half way up on the Gain control for Channel 1, the El Guapo starts to break up and becomes one of the richest and most responsive blues amps ever created! From there on up on the Gain control you’ll move out of blues tones and on into Hendrix inspired rock tones! Of course all of these tones are immediately available at your fingertips if you run the Gain control all the way up and use the volume control on the guitar to adjust the level of overdrive.

CHANNEL 2

“Jefe? Would you say I have a Plethora of Gain?” “Si El Guapo. You have a Plethora of gain.”

The second channel of the El Guapo picks up gain-wise where Channel 1 leaves off and is voiced brighter like the Super Lead circuit. Think of these two channels as an alternate personality of the same person. While the first channel on the El Guapo is voiced dark and rich, the second channel is voiced brighter with a controlled low-end and expanded top end range. Add to that a ton of available gain and tonal shaping options and the second channel of the El Guapo has enough gain to cover everything from early Van Halen to the hardest rock imaginable!

TONE CONTROLS.

The El Guapo contains a feature rich front panel that allows the player to sculpt his/her tone to perfection!

From Left to Right we have:

Inputs – The El Guapo features two inputs that feed the preamp of the amplifier. The top input should be used when maximum gain is desired or when using a guitar with low output. The bottom input should be used when maximum clean headroom is desired or with guitars that have high output. The bottom input has approximately a -6dB reduction in gain.

The front panel controls are: Gain.1, Gain.2, Treble, Middle, Bass, Master.1, Master.2 and Presence.

Gain.1 – Gain.1 adjusts the volume of Channel 1, the Super Bass Channel. This control, used in conjunction with Master.1 sets the gain to volume ratio of the first channel. Higher settings on the Gain.1 control will give more preamp overdrive and breakup. For the true vintage Marshall experience, I recommend that you turn the Master.1 control all the way up and use Gain.1 to adjust the volume of your clean channel. Doing so will bypass the Master.1 control and allow the Super Bass preamp to perform as it would on a vintage amp.

Gain.2 – Gain.2 adjusts the volume of Channel 2, the High Gain Super Lead Channel. This control, used in conjunction with Master.2 sets the gain to volume ratio of the second channel. Higher settings on the Gain.2 control will give more preamp overdrive and breakup. For a good balance with Channel 1, I recommend that you use Master.2 to set the volume of Channel 2 to match the volume of Channel 1. Remember you can use the Boost footswitch for an added Gain and Volume boost for solos etc!

Treble – The Treble control is used to fine tune the high-end response of the amp. Turning the control clockwise adds more treble.

Middle – The Middle control is used to dial in the mid-frequency response of the amp. There is a lot of flexibility in this control. Experiment to tune the amp to the guitar being used. Turning the control clockwise adds more mids.

Bass – The Bass control is used to fine tune the low-end response of the amp. Turning the control clockwise adds more bass.

Master.1 – Master.1 is used to control the overall volume of Channel 1 and can be used very effectively in conjunction with Gain.1 to set the overall gain and volume of Channel 1. Higher settings gives higher volume. To have Master control completely out of the circuit, turn it fully clockwise.

Master.2 – Master.2 is used to control the overall volume of Channel 2 and can be used very effectively in conjunction with Gain.2 to set the overall gain and volume of Channel 2. Higher settings gives higher volume. To have Master control completely out of the circuit, turn it fully clockwise.

Presence – The Presence control is used to adjust the intensity of the tone, making it sound more raw and present as the control is rotated clockwise. Experiment with this control along with the Treble control to dial in the high-end response of the amp.

VOICING SWITCHES.

In addition to the six knobs on the front panel, we have included six switches that allow for dramatic tone shaping all by themselves!

From left to right we have:

Channel 1 Bright Switch – We have included a 3-position bright switch for each channel of the El Guapo. The center position is the OFF position and adds no extra brightness to Channel 1 and is the core Super Bass tone. The B1 position adds a moderate level of highs to the tone to help guitar parts stand out more or when a brighter overall tone is needed. The B2 position adds additional brightness to what was added with B1 and is great when using dark guitars that need a high frequency boost in order to cut through the mix. Note: Increasing the Gain.1 control diminishes the effect of this switch.

Channel 2 Bright Switch – the Channel 2 Bright Switch performs the exact same function as the Channel 1 Bright Switch albeit with Channel 2.

Ch.1/Ch.2 – This is a manual channel switch control. Have you ever gotten to a gig and forgotten to bring your footswitch for your amp? If you do while using the El Guapo, we’ve got you covered since you can make the switch manually. Note: When a footswitch is plugged into the Channel Switching jack on the back panel of the amplifier it takes priority over the front panel switch and the front panel switch will cease to work.

NRM/BST –The Boost feature on the El Guapo is one of the most effective controls for taking the second channel from vintage to modern! When this footswitch-able feature is activated, additional preamp gain is added to the signal along with a subsequent boost in volume. This features is incredibly useful as a solo boost or as a higher gain preset. Like the Ch.1/Ch.2 switch, when a footswitch is plugged into the Boost jack on the back panel of the amplifier it takes priority over the front panel switch and the front panel switch will cease to work.

LO/HI – The Low Gain/High Gain switch is used to add massive amounts of gain to Channel 2 and also adds increased low-end and fullness and takes Channel 2 out of Vintage mode and into the Modern mode.

Response Switch – Possibly the most powerful and dramatic switch on the entire amplifier, the Response Switch alters the power amplifier stage and is almost like an era switch for classic Marshalls. In the JTM mode, the amp will take on the dynamics and response of a 1965 JTM45 with a fast and clean attack with added headroom and articulation. In the JMP mode, the amp breaks up a little more and mirrors the dynamic response of a 1968 100W Plexi with a looser response while staying very crisp with a lively attack. Finally the JXN mode is our own design, and when in this setting, the amp takes on a looser and more open dynamic response that is very similar to our Class A British Clean series of amps. Experiment with this switch and the Presence control to create your own ideal clean and overdriven tones. Note: The Presence control remains fully functional during all of these modes.

REAR PANEL

From right to left we have:

Parallel Speaker Jacks – Parallel speaker jacks allow the player to use more than one speaker cabinet at a time with the El Guapo. Because these jacks are wired in parallel, there is no difference in tone between them and either one or both can be used without effect.

Impedance Selector Switch – The Impedance Selector Switch allow the user to use the amp with any guitar speaker cabinet available as long as it is either an 8 or 16 ohm cabinet.

Channel Switch/Boost Footswitch – We have included a jack to insert a two button footswitch that will allow you to control the Channel Switching as well as the NRM/BST mode of the El Guapo remotely. For this to work properly you must use a footswitch that features a stereo cable as the TIP connection shorts to ground to activate Channel 2 and the RING must short to ground to activate the Boost mode. Note: When a footswitch is plugged into the Channel Switching jack on the back panel of the amplifier it takes priority over the front panel switch and the front panel switch will cease to work.

FX Loop – To make the El Guapo even more flexible, we have incorporated a buffered series FX loop between the preamp (post Master) and power-amp. Adding an FX loop here allows the player to use his/her effects in the loop and not interfere with the critical relationship between the guitar and preamp.

50W/100W Switch – This two position toggle switch is used to select either the 50W Class A/B or the 100W Class A/B power modes for the El Guapo. You should expect about a 3dB drop in volume when in the 50W mode.

B Fuse – This fuse is used to protect the amp in the event of a short in the high voltage circuit. replace only with a 1A Slo-Blo fuse rated for 250V

Standby Switch – This Standby Switch interrupts the high voltage DC inside the amp and effectively puts the amp in a resting state until the user selects the Play position.

Power Switch – This switch turns the amp on and off and when on powers the cooling fan and every circuit except for the high voltage DC circuit.

IEC Module – In addition to serving as the power entry for the El Guapo, the IEC module also doubles as a voltage selector for the amplifier and is used to select between either 120 or 240V operation. With this features you can travel worldwide with the El Guapo and regardless of line voltages have consistently great tone without having to carry a step-up/step-down transformer! Lastly the IEC module also contains the 4.0A Mains Fuse for the amp as well as a spare fuse.

Ben Fredricks

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