Darkglass Harmonic Booster Bass Preamp w/ Box & Manual

No sales tax for customers outside California.  

The Darkglass Electronics Harmonic Booster is a powerful clean bass preamp and tone enhancer designed to add clarity, harmonic richness, and definition without coloring your core tone. Built in Finland, it features a pristine preamp circuit with ±20 dB of clean boost, a semi-parametric mid control, and the signature Harmonic Enhancer that introduces subtle saturation and harmonic complexity. This makes it perfect for tightening your tone, improving note articulation, or enhancing an amp or DI setup for live or studio use.

This example is in excellent condition and includes the original box and manual. Controls include Volume, Mid Gain, Mid Frequency, and Harmonics, allowing players to tailor everything from scooped modern bass sounds to warm vintage-style presence. Whether used always-on or as a boost for solos, it delivers clean headroom with Darkglass precision.

Darkglass Electronics, known for artists like Billy Gould, Adam “Nolly” Getgood, and Tony Levin, designed the Harmonic Booster as a response to players wanting their signature tone enhancement without overdrive. It functions as a studio-grade clean preamp in pedal form.

At Mahar’s Vintage Guitars, every pedal is tested, photographed clearly, and described accurately.

We welcome trades and buy boutique and vintage gear. For more options, explore our Fender Amplifiers Collection, Vintage Fender Guitars, or visit our Sell or Trade Your Gear page.

Excerpts from actual user reviews on various gear forums:

• “Best always-on bass pedal I own—adds clarity and life.” – TalkBass
• “Harmonics control adds sparkle without distortion.” – Reddit r/BassGuitar
• “Darkglass tone without the dirt—perfect studio tool.” – BassChat
• “Makes every note clearer, especially in a mix.” – Harmony Central
• “Clean boost with subtle grit if you want it—fantastic.” – The Gear Page

Shipping policy:

Shipments will require signature on delivery, no exceptions.  If there is damage, the buyer must retain all packing materials intact and picture them immediately and send them to sales@maharsvintageguitars.com.  Less than 1% of our shipments are damaged in transit, and we are committed to making sure your item arrives safely, but we are taking these additional measures to make sure you are happy with your purchase.