18W EL84 Chassis Only



Product Description

This is a great amp for classic rock, blues, country or pop styles. Its two channels offer a wide variety of tones and can be easily switched with the use of an A/B pedal. Additionally, a “Y” pedal can be used to play both channels simultaneously for even more tonal variety. Amplifier heads have a 10 day trial period on black tolex cabs only. Custom color heads are not returnable.

Amp Features:

•2 channels

•Hand-wired in the USA

•Parallel output jacks

•Selectable 4/8/16 ohm output

•Cathode biased power section

•Tube rectified

•Tube Lineup: (3) ECC83/12AX7, (2) 6BQ5/EL84, (1) 6CA4/EZ81

Channel 1 (the right input) is based on the Normal channel from the Marshall 1974. It is a relatively simple C83/12AX7 preamp that features a tone control and a volume control. It is a very transparent channel that can go from clean to classic rock distortion. It cleans up really well when the guitar volume is rolled off.

Channel 2 (the left input) is a preamp based on a more modern design than Channel 1. It’s a higher gain ECC83/12AX7 preamp that features a 3-band tonestack, a gain control and a volume control. It has a fuller, more modern distortion tone than Channel 1 and the tonestack and volume controls allow for a wide variety of tones to be dialed in at various overall volume levels.

The poweramp uses a pair of 6BQ5/EL84 tubes in a Class A/B push-pull configuration. The power tubes are responsible for the classic overdriven tone that has made the original 1974 so popular. This amp is no exception and the power section distorts in a very pleasing way. The more you turn it up the better it sounds!

Construction Notes

This amp is completely hand-wired using quality components. The turret board construction makes it much easier to modify or replace components than printed circuit board construction.

Components Used:

•Mallory 150 caps

•Low-noise carbon film resistors

•Alpha pots

•Cliff jacks

•Carling switches

•Classic Tone transformers

•Full set of JJ or JJ/Sovtek tubes included

Other Notable Features

Starting with the preamp channels, Channel 1 is a very simple, clean preamp. It’s a single gain stage fed into the phase inverter. The volume knob controls how hard the phase inverter and power tubes get driven. Higher volume settings here produce the classic 18 watt power tube distortion.

The Channel 2 preamp produces much more distortion than Channel 1. It has 3 tone controls, a gain control and a volume control. The amount of preamp distortion can be set to taste and it allows for higher gain tones at lower volume than Channel 1. The volume control on Channel 2 works similarly to Channel 1 in that it controls how much power tube distortion is produced. The beauty of Channel 2 is that it gives you the ability to mix the preamp and power tube distortion levels. Use the Gain control to set the preamp distortion and the Volume control to mix in the appropriate amount of power tube distortion. The “sweet spot” mix of preamp/poweramp distortion will vary depending on guitar and speaker combinations used but once you find it, it can’t be easily beaten.

The poweramp is equipped with a modification known as the “Ruby Buzz Mod”. Basically, it’s a modification to the “stock” 18 watt power section that prevents crossover distortion buzzing without compromising the tone of the power tubes. This is a very popular modification on 18watt.com. Also included thanks to 18watt.com is what is known as the “Huge Cathode Bypass Cap”. As mentioned earlier, the power section is cathode biased. The “stock” 18 watt cathode bypass capacitor is replaced with one of a much higher value. This helps to stabilize the power tube cathode voltage and lends itself to a tighter overall feeling than the amp would otherwise have.