LDR3.V2 Passive Preamp


The LDR3.V2 has been updated to the LDR3.V25 which can be found here. 

The LDR3.V2 Passive Preamplifier is a remote controlled singled-ended audiophile grade passive (unity gain) 3 RCA input, dual (parallel) RCA output preamp/volume controller designed around Tortuga Audio’s third generation light dependent resistor (LDR) technology.

The LDR3.V2 is an updated release of our previously discontinued LDR3 model and incorporates our latest 3rd generation LDR control technology for exceptional performance.

The LDR3.V2 comes in black or silver anodized and also clear lacquered bamboo. It comes stock with Cardas gold RCA jacks.

SKU: LDR3.V2 Category: Tag:
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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 LDR3.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 LDR3.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 LDR3.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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