Catalinbread Announces Dirty Little Secret Deluxe

The Dirty Little Secret Deluxe represents the next logical step in Marshall Plexi emulations, reaching beyond the preamp circuit and adding the rest of the amp for an extremely authentic take on everything inside the chassis. 

Our original DLS circuit has been tweaked and upgraded throughout, now featuring a phase inverter, power amp sim and output transformer as well as some new features and the most requested modifications for the original. 

One such addition is a toggle switch on the outside to select between Super Lead and Super Bass modes, and we’ve also externalized the Presence knob to easily dial in your preferred Marshall flavor. Also added is a piece of the Dirty Little Secret – a single preamp tube simulator – as a built in boost circuit that can be used independently of the main circuit. 

You can run the boost and DLS in any order you like: put the boost before the DLS for a high-powered saturated tone or after to pummel the front end of your amp. A new tightness knob lets you shave off the sub-bass for a little extra clarity or completely attenuate the low end for some cool thrash medal tones. 

A Line Out jack gives you a dedicated +10dB output that you can use with a mixer or DAW, and you can use both outputs simultaneously. Between the Boost, order selector and the external Super Lead/Super Bass modes, the Dirty Little Secret Deluxe is engineered to be a total performance tool that does the line justice.

Manual Overview

If you’re reading this, the secret is out! What started as a fourth version of our flagship Dirty Little Secret ended up as this, the Deluxe version, which I’m sure you’ve already played before reading this. Quite frankly, we don’t blame you, and right up front we want to extend a hearty “hope you enjoyed it,” which you undoubtedly have. If you haven’t, good news! This manual will explain everything in great detail, be you a “play it first, who needs a manual” type or a “whoa there, let’s check the paper first” type.

The Dirty Little Secret Deluxe is dedicated to all things Marshall, featuring an all-discrete circuit with a preamp, phase inverter, power amp sim and output transformer. A built-in foot switchable boost modeled after a clean Marshall preamp and effect order switch gives you a fully-customizable amp-in-a-box experience.


MASTER: A descriptor that’s normally a formality, this knob occurs before the phase inverter and output transformer rather than at the end of the circuit, just like a real amp. We designed the output stage to be more impervious to input saturation than most power sections, so really cranking it doesn’t alter the tone in an extremely noticeable way. However, those that plan to use the DLS DLX as an always-on can find some subtle sag and gentle compression living within the whole of the volume knob.

PREAMP: We’ve taken the original preamp control and tweaked it to deliver a wider gain range with more cleans on the lower end and more cranked Marshall tones on the higher end.

PRESENCE: Formally an internal trimmer on the original, the Presence control is a powerful low-pass filter that attenuates frequencies by 3dB above 1.59Hz when turned all the way down, and the cutoff point climbs to an indistinguishable frequency by the end of the turn.

BOOST:  The boost circuit is actually one of the tube emulation building blocks that make up the DLS itself. When you run the boost before the Dirty Little Secret, it acts as another “preamp tube” added to the front end of the device for some saturated JCM900 tones. When run after, it makes everything louder without sacrificing the clarity.

Learn more about Catalinbread’s Dirty Little Secret here.