A Flexible High Performance Passive Preamp

The LDR3000P is Tortuga Audio’s flagship passive preamp for the discerning audiophile who appreciates the best that a passive preamp has to offer.

The LDR3000P is designed around our proven 4th generation remote controlled V25 volume/preamp controller that uses digitally controlled analog light dependent resistors (LDRs) to provide smooth 100 step volume control over a 60 dB range. Features include ramped muting/unmuting, channel balance adjustment, input switching, mono mode, plus our highly unique adjustable input impedance. Built-in calibration of the replaceable socketed LDRs ensures accurate attenuation, channel balance and optimal performance over the extended life of the preamp.

The LDR3000P is easy to operate via an intuitive interactive menu driven control interface designed around  the 7-button Apple remote and a bright easy to see 256 x 64 pixel white-on-black graphic OLED (Organic Light Emitting Diode) display.

The result is an outstanding audiophile grade passive preamp that combines advanced LDR (light dependent resistor) technology with a contemporary minimalist visual interface designed to satisfy the most demanding audio enthusiast.

Passive Preamp for both Single-Ended & Balanced Systems

Whether you have RCA gear, run with all balanced, or a mix of both, you don’t have to choose because the LDR3000P Passive Preamp handles both. There are 3 sets of RCA inputs and 3 sets of XLR inputs that you can use in any combination. The RCA and XLR outputs carry the same output signal regardless of the signal source type although the balanced output will only have one phase active (pin #2) if the input source is single-ended.

What To Expect from this Passive Preamp

If you haven’t tried a passive preamp before, or even if you’re already a fan of passive preamps, the LDR3000P will likely surprise and delight you.

The words people use to describe our LDR preamps include colorless, transparent, neutral, articulate, clear, fuzz-free, clean and natural. Paired with a high quality source component you can expect satisfying dynamics, a beautiful mid-range, and surprisingly solid bass. The 100 step attenuator is ultra-smooth with no clicks or pops and no mechanical contacts to corrode or wear out – you won’t even realize the preamp uses a stepped attenuator.

The consensus of customers and reviewers is you can expect performance  that is superior to conventional passive preamps utilizing even the best audiophile grade potentiometers, stepped attenuators  and most transformer based volume controls.

When well matched with source components that have a robust output stage,  you’ll be hard pressed to find a better preamp anywhere regardless of price.

Passive Preamp Key Features

LDR Volume Control

Light Dependent Resistors (LDRs) are at the center of Tortuga Audio’s passive preamp technology. LDR based volume control deliver a clean, neutral yet satisfying sound that defies explanation but is nevertheless undeniable.  The result is a super smooth 100 step analog volume control complete with channel balance adjustment, muting and mono mode.

OLED Display & Remote Control

We’ve done away with all conventional buttons, dials and switches and replaced them with a single multi-function encoder control knob and a contemporary menu driven OLED display and a simple 7 button Apple remote. Audio gear for the 21st century.

Dead Quiet Signal Path

With no active signal amplification or buffering the LDR3000P is true unity gain preamp designed solely to provide passive volume control and input switching. The absence of actual signal amplification (gain) is rarely a drawback since nearly all source components have sufficient line stage output voltage to drive most amplifiers to ear splitting volume levels. Why amplify when you don’t need to. Go passive.

Built-in LDR Calibration

Just like tubes, LDRs are analog devices subject to aging and performance drifting over time. Unlike tubes,  our LDR preamps have built-in calibration that adapts to the LDRs as they age and to calibrate a new one if it requires replacement (all LDR modules are plug-in replaceable). This provides added assurance that your preamp investment will hold its value over the long haul.

No Relays In The Signal Path

LDRs are also used for smooth audio input switching thus eliminating the use of noisy electro-mechanical relays and their mechanical switching interface points.

Replaceable Plug-in LDR Modules

LDRs are estimated to have a useful life upwards of at least 50,000 hours. However, just like tubes, some may fail earlier or go sufficiently out of spec over time to warrant replacement. And just like tubes, our plug-in LDR Modules are easily replaceable ensuring the lasting value of your preamp investment.

Firmware Update via USB

Our software driven preamp controller can be easily updated by the customer via a pair of USB ports located on the rear panel. Software updates can downloaded from our website and uploaded into the preamp via a simple PC application.

Passive Preamp Specifications

These specifications reasonably reflect the current model but are subject to updating and modification without notification.