The Atlantic 4.0 is Jackson Ampwork's tribute to one of the greatest amp designers of all time; Ken Fischer of Trainwreck Circuits and his legendary Trainwreck Express. Not a clone by any stretch of the imagination, the Atlantic 4.0 is Jackson Ampwork's take on how a high gain, non-master volume amp should be done and incorporates features never before seen in an amp of this class!

The Atlantic like the Trainwreck series of amps is built for the serious player who wants to cover a gig with nothing but a guitar, a cord and an amp! Every shade of overdrive you could ever want is available from the Atlantic 4.0 with nothing more than a twist of your guitars volume control! With the players volume control lowered, the Atlantic 4.0 delivers the chimiest most harmonically rich clean tones you have ever heard and when raised, the amp seamlessly transitions to over the top screaming overdrive all with nothing more than a twist of the guitars volume control!

FEATURE RICH FRONT PANEL

From Left to Right we have:

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

The front panel controls are: Volume, Edge, Treble, Middle, Bass and Presence.

Volume – The Volume control works to not only control the volume of the amp but also doubles as the gain control for the amp. We recommend setting the Volume control to the maximum level of overdrive desired and then use your guitar’s volume control to adjust this level of overdrive. Remember you can use the Boost footswitch for an added Gain and Volume boost for solos etc.

Edge – The Edge controls acts as a master tone control for the amplifier and is a passive control used to refine the high end of your tone. Fully clockwise is off.

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.

Presence – the Presence control is used to adjust the intensity of the tone, making it sound more 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.

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

From left to right we have:

NRM/BRT – This is a Bright Switch that is used to increase the amount of high-end in the tone. Increasing the Volume Control diminishes the effect of this switch.

SC/HB – The Single Coil/Humbucker Switch is used to approximate the difference in sound between that of a Single Coil and a Humbucking pickup. If you are using a guitar that is thin sounding and want to beef up your sound, select the HB position. Conversely, if your guitar is very fat sounding and you need more articulation, select the SC position. This is a very effective control!

THN/THK – Similar to the SC/HB switch, the Thin/Thick controls is used to adjust the response of the amp to that of your guitar. While the SC/HB switch shapes the EQ of the amp right at the input, the THN/THK switch shapes the EQ of the amp at the output. Both of these controls produce similar but different results and when used together can enable the guitarist to essentially rewire the amp on the fly! Experiment and find your own voice with these controls!

LoG/HiG – The Low Gain/High Gain switch is used to select the amount of “push” in your clean sounds. Set to LoG, the cleans are very clean almost like a Blackface Fender. When set to HiG, the cleans are more aggressive like a Blackface Fender with it’s volume control cranked! Increasing the Volume Control diminishes the effect of this switch.

ON/OFF – Possibly the most powerful and dramatic switch on the entire amplifier, the ON/OFF switch turns the Presence Control On or Off and in doing so respectively adds or removes negative feedback from the amp. In the ON position, the Presence control is active and the tone of the amplifier is very tight with a controlled and percussive low end with more clean headroom. Switching to the OFF position, the Presence control is inactive and the tone and feel of the amplifier is much looser with a more aggressive tone and much more overdrive available! In the OFF position the amp has a response that is similar to a cranked Vox AC30 and when ON the amp has a response like a vintage Marshall Plexi. Be careful with this control, it can take the amp from mild to wild in an instant!

FEATURE RICH BACK PANEL.

The back panel of the Atlantic is one of the few amps available whose back panel is as feature rich as its’ front panel!

From right to left we have:

Boost – The Boost feature on the Atlantic 4.0 is one of the most effective keys for taking the amp from tame to savage! 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.

FX Loop – To make the Atlantic 4.0 even more flexible, we have incorporated a series FX loop between the preamp 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.

Parallel Speaker Jacks – Parallel speaker jacks allow the player to use more than one speaker cabinet at a time with the Atlantic 4.0. 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.

Wattage Switch – This three position rotary switch is used to select either the 15W/30W Class A, 25W Class A or the 50W Class A/B power modes for the Atlantic 4.0. Note: The amplifier should be placed on Standby before changing power modes and given a 10 second rest period after changing power modes. Doing so will give the voltages inside the amplifier time to settle before playing.

15W/30W Switch – This two position toggle switch is used to select either the 15W Class A or the 30W Class A power modes for the Atlantic 4.0. In the 15W position the Atlantic is using (2) EL84′s to produce 15W and in the 30W position the Atlantic is using (4) EL84′s to produce 30W. This switch has no effect when the rotary switch is set to the 25W or 50W modes.

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.

Bias Trimmer – To make changing tubes easier, we have included an external bias adjustment that is used to adjust the plate current of new tubes when they are installed. Simply attach a multimeter (set to read mV) to the red and black tip jacks and adjust the trimmer until the multimeter reads 35mV. Note: This is ONLY for use in the 50W mode and with EL34 tubes exclusively!

IEC Module – In addition to serving as the power entry for the Atlantic 4.0, 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 Atlantic 4.0 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 3.0A Mains Fuse for the amp as well as a spare fuse.

B Fuse – This fuse is used to protect the amp in the event of a short in the high voltage circuit.