LDR1.V2 Passive Preamp



The LDR1.V2 Passive Preamplifier is a single RCA input, singled-ended audiophile passive (unity gain) preamplifier complete with remote control. Equipped with dual (parallel) RCA outputs, the LDR1 is designed around Tortuga Audio’s latest generation light dependent resistor (LDR) technology.

The LDR1 is a single input version of our popular LDR3.V2 Passive Preamp and benefits sonically from having eliminated all input switching hardward.

The LDR1 comes in black or silver anodized and also clear lacquered bamboo. It comes stock with Cardas gold RCA jacks.

SKU: LDR1.V2 Category: Tag:
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The LDR1.V2 Passive Preamp is a single input version of the popular 3-input LDR3.V2. Other than having 2 fewer inputs, a key difference is that the LDR1 eliminates input switching hardware thus providing a more direct input and output path for the audio signal. Similar to the LDR1B.V2 balanced version, we believe this simplified signal path gives the LDR1 slightly improved sonic performance over its multi-input brethren.

Subjective Performance

Characteristics – Colorless, transparent, neutral, articulate, clear, fuzz-free, clean, natural, high resolution, great mid-range, solid bass. These are words and phrases commonly used by both customers and reviewers to describe the LDRx passive preamplifier sound.

Compared To Other Types of Passives – 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 resistive attenuators or even most transformer based volume controls.

Compared To Active Preamps – Independent reviewers have found that the Tortuga passive preamps match the performance of even the finest high-end preamps costing many thousands of dollars more.

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Key Features Under The Hood

Optically Isolated Passive Attenuation – The LDR1.V2 is a true passive preamp insofar as there’s no amplification or buffering of the audio signal notwithstanding the presence of a power supply.  Audio signals are optically isolated from both the power supply and the LDR control circuitry.

3rd Generation LDR Technology:  The LDR1.V2 is built with our 3rd generation LDR3x.V2 preamp controller which employs microprocessor controlled analog light dependent resistors to provide audio attenuation and input switching with unparalleled audio quality.

Auto Calibration: Similar to tubes, LDRs are analog devices subject to aging and drifting over time. Unlike tubes, the LDRx & LDRxB employ self-contained auto-calibration to keep the unit in precise calibration. This provides added assurance that the preamp will hold its value over the long haul.

LDRs For Input Switching:   The LDR1.V2 also uses LDRs for audio input switching in lieu of relays. Auto Calibration does employ relays but these are physically disconnected from the audio signal path during normal operation.

Software Updates via USB: If warranted, software can be easily updated by the customer via a USB port located on the rear panel. Software updates can downloaded from our website and uploaded into the LDRx from a laptop or desktop PC. Eventually, we hope to make the possible from a Mac as well.

Replaceable LDR Modules:  While the useful life expectancy of LDRs are estimated to be upwards of 50,000 hours, just like tubes, some may fail earlier or go sufficiently out of spec over time to warrant replacement. And just like tubes, our LDR Modules are easily replaceable ensuring the lasting value of your passive preamp investment.

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Available Options

  • Front Panel
    • Clear silver anodized aluminum
    • Black anodized aluminum
    • Bamboo
  • Power Supply
    • 120 VAC (domestic) – 12 VDC 0.5 amp linear regulated external “wall-wart” style power supply – 2.1mm pin (positive)
    •  240 VAC (international) – 12 VDC 1.0 amp switching power supply “brick” with detachable IEC power cord with US AC plug – 2.1mm pin (positive)
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