LHZ HL-1 HAZard LAMPS Bass Pedal

LHZ-04 Bass Guitar Preamp

According to Lonnie West, the LHZ-04 Bass Guitar Preamp is a faithful re-creation of the circuit used in late ‘80s and early ‘90s HazLabs bass preamps to create that classic and elusive Spector tone. The LHZ-04 is a component-level clone of the pre-Kramer HazLabs preamp which was designed to push its opamp circuit into nonlinear operation only during the extreme peak signal transients that occur when the bass is played aggressively. Played with a normal or light touch, the preamp provides a clean bell-like tone. When played aggressively, this preamp provides a subtle tubelike compression and adds distinctive high-frequency harmonic overtones to the sound that perfectly accentuates the Spector growl.

The audio sound clip sample features an earlier LHZ-03 installed into a white Euro4 LE with an EMG P/J pickup configuration plugged into a Hartke® HA5500 head (with the EQ flat), with a SUNN® 4X10” speaker cab and recorded directly from a Google Pixel 3 smartphone. I was so impressed with the sound upon hearing this low-tech audio capture that I felt it was imperative to share a snippet to demonstrate that the LHZ-03 bears the unmistakable HazLabs growl that is such an inherent attribute of the Spector NS-2.

Lonnie West, LHZ’s founder, spent most of his career as an engineer designing controls and software systems that integrate factory robotics with enterprise manufacturing systems. His alter-ego outside of this day job is writing and performing with original and cover bands. He got his first Spector bass, a Rebop 5 DLX with Zebrawood body, in 2010. “I loved and hated that bass,” he recalls. “It looked great and played like a dream. Unplugged, it had this wonderful growly tone. Plugged in, it was always a struggle. I wanted that Eddie Jackson [Queensrÿche bassist] style of tone, but it never quite got there, no matter how many pickup and preamp replacements I tried.”

When COVID hit, West found he had a lot of time on his hands, so he got back into a childhood hobby: electronics. “I forgot how much intuitive raw magic there is working with analog circuits,” he explains. “Where experimentation, instead of simulation, is the only rulebook.” He was on the verge of selling his Rebop until he stumbled across a thread on the TalkBass forums where someone mentioned that the Rebop is a fantastic bass that would sound very much like a USA Spector if you could put a Hazlabs in it. West couldn’t justify spending $400+ for a 40-year-old HazLabs preamp, and Sheldon Crane wasn’t making the SNC HazLabs clone anymore (another story for another time, perhaps), so he decided to make his own. Instead of copying the HazLabs board design, with pots mounted in it, West sought to craft something small and modular, making it easy to swap out the pots. “It was universal enough that I could mount it in project basses with small compartments,” he details. “The real question was, can this seemingly simple little preamp circuit really make as much difference as people said it did?” The answer, of course, was a resounding yes.

One might wonder how West is able to create such a spot-on replica of the original design without running into patent issues. Electronic circuits are notoriously hard to patent because it requires showing that you’ve truly invented something brand new that had never been done before. “That’s difficult to do because almost any circuit created today is a derivative of a design that’s been in the public domain for a long time,” explains West. “When I finished the first LHZ prototype, I started receiving inquiries about selling it. Having spent my career in corporate systems development, I am keenly aware of intellectual property rights. I couldn’t sell the LHZ without risk of litigation if HazLabs had patented the circuit design, so I started researching.”

It turns out that HazLabs didn’t patent their preamp. Why? Because it’s using the “Negative-Feedback Tone Control” circuit that was released into the public domain in 1952 by its inventor, P.J. Baxandall. He published this in the October 1952 issue of Wireless World, which was a magazine dedicated to radio and electronics hobbyists. At the time, this was a revolutionary new approach to EQ circuits that had not been done before. P.J. Baxandall could have patented this EQ circuit back then and made a fortune on the licensing right. Instead, he decided to make it public domain.

HL-1 HAZard LAMPS Pedal

The HL-1 HAZard LAMPS pedal brings the unique tonal voice of the LHZ preamp into a pedal format and is intended for players with passive basses who want the same punch and power as a USA Spector bass with an internal HazLabs preamp.

According to the LHZ website, while guitarists often change instruments live to provide a diverse variety of tones, this is a more challenging scenario for bassists. Changing the sonic profile, dynamics, EQ, and level of a bass, during a show, changes the foundation of the entire mix. The problem is that the tone control on a passive bass only cuts frequencies; it does not boost them. Passive bass tone controls rolled all the way to MAX are the same as an active bass set at the FLAT position. Switching from a dimed Spector to a passive bass (with effectively FLAT EQ) results in a significant difference in levels and tone that makes it difficult to balance instruments using the same signal chain (the accompanying video demonstrates this comparison using a dimed Spector and flat EQ passive bass).

So, how do you switch between a Spector with a “dimed” EQ and your favorite passive Fender® Jazz Bass® without adversely impacting the entire mix? The HAZard LAMPS pedal gives a passive bass the same active EQ control as a Spector with a HazLabs preamp in it. A passive Fender Jazz with the HAZard LAMPS bass and treble controls set to the same position as a Spector will provide the same output level, same EQ response, and the same unique sonic fingerprint as the Spector. Your bass will still sound like itself, so a Fender will have its characteristic Fender sound and a Rickenbacker® will still sound like a Rickenbacker. But the HAZard LAMPS will have the following impact: the output levels and EQ will be the same as the Spector, so there is no need to adjust anything else in your signal chain to compensate for the difference when switching basses, and the HAZard LAMPS will provide the same subtle harmonic overtones and slight sense of compression when played aggressively as the Spector does. This brings out articulation and nuances that are subtle, but help ensure every nuance of your performance is heard clearly.

Despite the success of both the onboard and pedal preamps, West says he never intended on starting a company. “I like to say that I accidently started a business: it was all trial and error. Listening to client feedback, making improvements to the design and documentation, and countless conversations with bassists all over the world—that community really inspired me to push forward with this project, and that community is still the heart of what I do today.”