HALF-LIFE Custom Amp Head 20w
We are extremely excited to announce the addition of a new favorite, our Half-Life 20w amplifier, now available to custom order!
Imagine the late 60s 'Super Bass' circuit subjected to radioactivity and aged for 10 years, then applied to a pair of fixed bias 6V6s. Consider the radioactive decay during that time producing some very unusual changes to that circuit that resemble what initially was a stock 'Super Bass' front end but has now mutated into a high tweak derivative of a nuclear powered 2203/JCM800, at 20w. Dumble was a brilliant artist. We love vintage Marshalls, particularly when they sound like they are going to explode, as well as old Bassman heads that were rebuilt as such by a legendary builder. This is our Half-Life amplifier.
What we strive for with each of our amplifiers is versatility. Although the Half-Life circuit is not the most versatile circuit we've produced, the dynamic range available encompasses much. Mostly overdriven, but cleaner with the Gain control set lower and the Level set higher. "Tough guy cleans" as a Clevelander might put it. Our ideal Marshall tones are varied levels of overdrive and dynamics. The harmonics generated by this circuit are extraordinary.
The configuration of the amp starts with the Gain control and it sets the overdrive content and harmonics of the preamp. The Level serves as a master volume and very capably allows the output section to run cleanly or be driven well into distortion. In typical Marshall style, the Treble, Bass and Middle controls are situated after the cathode follower circuit while the Accent control (Presence) is located in the phase inverter circuit and conveniently adds high end response if desired, or nothing. Located between the Gain and Treble controls, and very nearly hidden in plain sight, is the most effective feature this circuit offers; a mid boost/reduction circuit that dramatically alters the midrange curve and gain as it is used. In the down position, preamp gain is attenuated and the frequency response of the tone controls is altered. When switched up, preamp gain is restored and results in a tremendous boost relative to the down position, in addition to the familiar, characteristic midrange hump. Additionally, a middle position was added that disconnects the tone controls, dramatically accentuating upper mids and severely limiting lower mids and bass frequencies, inducing Vox style tones that can be harmonically explosive when turning the Gain control to maximum, reminiscent of the early 60s diamond checkered "Brilliant" tones!
Further enriched is our Half-Life output section, by modifying values to react more like that of a Trainwreck amplifier and deliver what could be described as the 'brown sound'. This allows more gain to be applied to the output tubes, softens the attack slightly and achieves a more harmonically pleasing response that is less harsh and better serves the nature of the preamp's capabilities.
Note: When changing output tubes, re biasing is necessary to appropriately set idle dissipation. This should only be performed by a qualified technician!
Tolex and grille cloth are 100% custom! Choose the options you would like and add associated reference # or name in the notes at checkout. Please note that once ordered, options chosen cannot be changed. Use these links for references to materials:
NOTICE: Marked as "In Stock" with a lead time. As each unit is custom, lead times will vary, depending on desired specs and availability of some custom spec'd parts and build time of cabs.
Here's a brief rundown of features:
- 20w
- High gain
- 6V6 output pair (fixed bias)
- 12AX7/ECC83 x3
- SS Rectifier
- 'Gain' & 'Level' controls
- Full tonestack & 'Accent' control
- 'Mid' 3 position toggle switch
- 4, 8, 16 ohm output via 3 position rotary switch
- Optional gold/black or black/white faceplate & backplate
- Mains optional 120/220/230/240vac @ 50/60Hz
We look forward to building you our new favorite 20w head! The harmonic complexities our Half-Life delivers are second to none!