Welcome to the old west where the “Axe” slingers are well known for their signature tones. When you step up to the plate to achieve a hallmark classic tone you’ll want a Plexi 45 in your corner. The Plexi 45 is not just a resurrection of the tried and true, it’s even better.  

Made for the player whose tonal diversity requires clarity and soul filled singing leads, the Plexi 45 will deliver. Specially developed for the classics, the Plexi 45 can help even the novice player sound seasoned. The Plexi 45 is equipped with two (2) 6L6 or EL34 power output tubes, one (1)-GZ 34 tube rectifier and three (3)-12AX7 pre-amp tubes.

Special attention has been paid to the amplifier's chassis layout to ensure that each component is placed in an exact location. From the transformer layout to the interior assembly, the Plexi 45 is faithful in its classic design. High quality parts are utilized to ensure many years of excellent sound and performance, a Mojave AmpWorks trademark.

Classic details — If you look under the hood of a Plexi 45 you find many details that collectively set it apart from modern built amps. From the careful selection of power and standby switches to the sideways interior mounted capacitor, the Plexi 45 captures a unique architectural character that is sought after by many vintage amp enthusiasts.  

Adjustable Fixed Bias

An adjustable bias pot makes it easy to service the amplifier when changing tubes. The Plexi 45 can be run with: KT66, 6L6, 5881 or EL34 power tubes to suit the taste of the user.  

Laser Etched Panels

Laser etched front and back control panels are long lasting compared to painted lettering.

Power Dampening

Power Dampening is a unique feature that allows infinite power levels to be selected. With the Plexi 45 you can dial in anywhere between the maximum 45 watts to a minimum as low as 2 watts output. If you need to get a full throttle overdrive tone, but at a volume you can play at home, then you can select the power or volume level that works best for you and still get the same tone you had with the amp cranked up.

A non-master volume amp does not have preamp distortion and normally needs to be run at high power levels to achieve an overdrive sound. Higher power levels result in higher volume. With Power Dampening the user can select what power level they want to use. By reducing the power the amp can make, the volume will be reduced with it. Because Power Dampening lowers the power being generated by the tubes, the amp runs cooler, and with much less stress. This reduces wear on the tubes and transformers. Power Dampening is not a built in attenuator, nor is it a master volume control. The result is excellent retention of both tone and clarity. Power Dampening lets you get full throttle overdrive with lower power amp volumes.

Line Level Output

All Mojave Amplifiers are equipped with adjustable line level outputs. The adjustable Line output is also equipped with a ground lift, selected via a push-pull knob, to avoid any ground loops that might occur from direct connections with external equipment. Line outs serve as an excellent source for collecting the amplifiers sound as a whole without microphone or speaker interaction. The tone is also inclusive of the power tubes and output transformer. By using the line level output the guitar amplifier signal can be sent directly to a live board, recording device, effects processor and amplified separately allowing wet/dry setups.

Top quality components

Top quality electrical parts are just another feature that help make the Plexi 45 an exceptional value. The Plexi 45 shines inside and outside, as much as it shines sonically.

Non-magnetic Aluminum chassis

Quality starts from the ground up. The Plexi 45 has been built on a thick folded Aluminum chassis. Each corner of the Plexi 45's chassis has been welded for added strength and support. Building a guitar amplifier on an Aluminum chassis has several key benefits. The first of these benefits is that Aluminum exhibits a non-magnetic behavior. Power transformers create magnetic fields, and because of its inherent properties the Aluminum chassis will not interact with these fields, thereby reducing 60Hz hum. In addition, Aluminum cannot rust like steel and is many times lighter than steel.  

Hand built Terminal board electronic

Terminal boards are just another intelligent construction feature within the Plexi 45 amp. Terminal board construction is extremely reliable because of superior mechanical contact between the parts and the connecting wires. Mechanical strength is achieved when the leads from the parts are fed directly into the turrets themselves and then soldered for guaranteed electrical bonding. Terminal board construction provides ease in changing circuitry as ongoing development occurs.

Metal Film resistors are used rather than the typical carbon composition or carbon film type resistors. Metal film resistors can be obtained in precise values and also boast greater temperature coefficient ratings, which in turn make the part very stable and less likely to drift from its original value. Each resistor found within the Plexi 45  amplifier has been specified and designed to have a greater power rating than the circuit actually demands. This will ensure longevity of the part and proper circuit operation for the life of the amplifier. Metal film resistors are also superior with regard to noise, unlike their carbon composition counterparts. 

Carbon composition resistors are typically very noisy, giving rise to an increased hiss when the amp is on. Metal film resistors, on the other hand, are extremely quiet. This factor proves to be very desirable, especially when recording.

Custom made 1% tolerance capacitors are utilized throughout the Plexi 45 amplifier, which provides for sonic consistency from one amplifier to the next. The capacitors used within the Coyote amplifier are of the high-grade film and foil polypropylene and silver mica varieties.

Ceramic Tube sockets are also a part of the Plexi 45's high grade component makeup. Ceramic sockets do not burn and are less likely to arc with the high voltage present at the tube pins. Lower grade tube sockets such as phenolic or plastic can burn and cause a carbon resistance to form, which in turn will increase arcing between the high voltage tube pins.

Hand tested select matched preamp and power tubes.  Mojave AmpWorks tests all of the tubes it uses in every Plexi 45. This step will ensure that each amp has minimum hum and a balanced gain. Balanced pre amp and power tubes provide the amplifier with improved clean headroom and smooth overload tones that move fluidly from one sound to the other. This step requires the personalized attention that is synonymous with the entire construction process involved with the Plexi 45.

 The Plexi 45 amplifier has been completely hand-wired with Teflon insulated silver-plated copper wire. Teflon insulated wire will not burn like plastic coated wire. Teflon insulated wiring also resists heat, preventing cracking of the wiring insulation. In addition, silver-plated copper wire is an excellent conductor.

Creating a Better Guitar Amplifier

The first way to improve any design is to learn from the past. Mojave AmpWorks has the distinction of having a great deal of experience in the restoration and service of vintage guitar amps. A large part of our experience has been gained solving problems with older guitar amps that had many miles on them. All amps start out new and wind up old. It comes down to how they weather the wear and tear. 

 Central point electrical groundin

Central point grounding is favored for its lower noise and its increased grounding facilitation. Central point grounding reduces ground loops while also improving conductive points for each area requiring ground connection. Power amps are better served when grounds are brought together to their respective points and not just made in different points across the chassis.  

A detachable AC receptacle with built in fuse holder is a good start. Most amps built today have a detachable AC cord as opposed to the AC power cord being permanently attached to the chassis. By using a detachable AC power cord, it can easily be replaced in the event that it becomes cut, frayed or damaged. This is a lot less hassle than having to change a power cord that is permanently attached to the chassis.  

A built in fuse holder that also contains a spare fuse has it’s advantages. The main benefit of having the fuse holder built into the AC receptacle is that there is no fuse holder protruding from the chassis back panel. Items such as fuse holders that protrude from the back of the chassis are subject to breakage in the event there is an impact along the back panel of the amp. A broken fuse holder or missing fuse cap will render the amp useless. This is an all to common problem among both vintage and modern amps which use that design. Mojave AmpWorks  amplifiers have the fuse holder safely packaged within the confines of the AC socket. An added bonus is the convenient spare fuse that is stowed inside the fuse holder itself.  

Speaker connection is easy and dependable. One problem encountered by guitar players is knowing what settings to use when running more than one speaker cabinet. Mojave AmpWorks  amplifiers have clearly marked back panels making it easy to understand and use. There are no “Impedance Selectors” on the Mojave AmpWorks  amplifier. Impedance selectors are switches or contact plugs that wear out over time. This creates an opportunity for noise and intermittent operation due to poor contacts within the switch or plug. Mojave AmpWorks  amplifiers are trouble free and easier to use without these switches. As a result, Mojave AmpWorks  amplifiers are also more dependable.  

 Well Grounded input jacks prevent your amp from becoming a radio receiver! The most common cause for radio frequency amplification by a guitar amplifier is poor grounding on the input jacks. Amplifiers that are designed around a mechanical ground from the input jack to the chassis have an open door for this problem. If the contact between the input jack and chassis corrodes the ground is poor and you will become an antenna when you plug your guitar cord into the amp. To prevent this action, the Mojave AmpWorks  amplifier has no mechanical ground made at the input jack, rather there is a solid ground made with a soldered connection directly to the input jack.  

Dual-Primary Power Transformers.

The Plexi 45 is built with a High Efficiency Dual-Primary power transformer. This means higher efficiency and cooler core temperatures. The result is a more reliable power supply with better current capacity. The Plexi 45 is also designed with a larger power supply filtering system resulting in better clean headroom and dynamics. Upgrades like these are all part of the improvements built on classic designs. Power transformers are built with low profile lugs rather then bulky wires sprouting out from the transformer making the amp cleaner and neater on the inside.

Plexi 45 - Head

6L6 Output Tubes

L = 20.25” x W = 8.75” x H = 9.5”

Weight = 28 lbs

$2,795 now only $1995 approx. 1435 Euro

Order with a 2x12 cab and save $200

Plexi 45 - Head

EL34 Output Tubes

L = 20.25” x W = 8.75” x H = 9.5

Weight = 28 lbs  

$2,795 approx.2008

Plexi 45 - 2x12 Combo

(2) G12H 30W Ceramic

L = 29” x W = 10” x H = 21.5”

Weight = 62 lbs

$3,125 approx.2245

Plexi 45 - 2x12 Combo

(1)G12H 30W Ceramic

(1)G12 15W Blue AlNiCo

L = 29” x W = 10” x H = 21.5

”Weight = 62 lbs

$3,285 approx.2360

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