About

Tortuga Audio designs and builds LDR-based preamp controllers and attenuators for DIY audiophiles and audio electronics enthusiasts. The current product line centers on the ePot.V4 Preamp Controller system — a digitally controlled, remotely operated volume control and input switcher that uses light dependent resistors instead of mechanical potentiometers or stepped attenuators.

We control volume with light. Specifically, LDRs (light dependent resistors) driven by LEDs create a continuously variable attenuator with no mechanical contacts, no wipers, no switches — a volume control that’s essentially a variable resistor controlled by software.

The V4 system’s key technical differentiator is its in-situ calibration algorithm. Most LDR-based designs require pre-matched LDR sets, which are expensive, time-consuming, and limit serviceability. The V4 instead normalizes the behavior of four LDRs in under 15 minutes via a user-initiated calibration cycle — no matching required. Install four LDRs from the same batch, run calibration once, and the firmware compensates for individual LDR variance.

The V4 system includes the controller board, the current 4-LDR attenuator module, an OLED display, remote control, an optional buffer board for active preamp applications, and a 5V linear power supply. The legacy LDR module for V2/V25 boards is still sold to existing owners for upgrades.

Tortuga Audio is a small operation based in central Oregon, selling direct through this site and by word of mouth in the DIY audio community, primarily on AudioCircle. Components are sourced both domestically and internationally; all assembly is done in the US.

The company was founded in 2010 in south Florida and relocated to Oregon in 2023 — a move that effectively stood the business down for about two years while a new shop was being built. We’re intentionally low volume: a niche within a niche, serving people who want something specific that’s rarely available off the shelf.

I started Tortuga Audio because I wanted LDR-based volume control for my own system, and nothing on the market did what I needed at a price that made sense. So I designed it, built it, and realized other people wanted the same thing.

I’m an engineer by training and career — technology and business development, solving problems that need both hardware and software. Audio electronics is where that intersects with a long-standing obsession with music and gear. Well-recorded music deserves capable playback equipment, and "capable" doesn’t require mortgage-level spending or magical thinking about wire directionality.

The shop is currently under construction, with completion expected mid-2026. Once that’s done, there will be room to evaluate whether small-batch finished preamps make sense alongside the DIY controller systems.

If you have questions about the V4 system, LDR technology, or whether this approach fits your application, see Contact — email is the most reliable way to reach us.