LDR3.V2K Passive Preamp Kit

LDR3.V2K Passive Preamp Kit

Price: $795

This is a legacy product and is no longer produced or sold by Tortuga Audio.

This V2-generation kit was eventually replaced by the LDR3.V25K kit, built around the newer V25 preamp controller.

The LDR3.V2K is a complete 3-input, 2-output single-ended passive preamp kit, substantially identical to the LDR3.V2 Passive Preamp. The kit includes everything needed to assemble a complete audiophile grade passive preamp: enclosure, front/rear panels, dual visual displays, RCA jacks, power supply, manual encoder/knob, remote, and wire.

State-of-the-art LDR-based technology

The kit is built around the LDR3x.V2.1 preamp controller board — the same core board Tortuga Audio used in all its LDR passive preamp products at the time.

High quality enclosure

The kit uses the same uni-body extruded aluminum enclosure used in the finished LDR3.V2 and LDR1B.V2 preamps. The front panel is 0.25" thick smoke-gray see-through acrylic, behind which the dual display modules mount. The rear is a brushed anodized aluminum panel with milled openings for all audio and power connections, including the RCA jacks and a USB connection for firmware updates.

Ready-to-use circuit boards

The circuit boards ship fully assembled and tested — no soldering individual components onto circuit boards. Assembly and point-to-point wiring is all that’s required.

What’s included

Qty Item

1

LDR3x.V2.1 preamp controller board

1

2.95" x 6" x 8" black powder coated extruded aluminum enclosure box

1

0.25" x 2.95" x 6" see-through dark acrylic front panel, cut for the encoder and knob

1

0.08-0.10" x 2.95" x 6" black anodized rear panel, cut for jacks

1

Knurled black enameled Fender Telecaster-style encoder control knob

4

Peel-and-stick urethane rubber feet

10

Standard gold plated brass RCA jacks

1

DC power jack

1

12 VDC trigger-out phono jack

8

Sets of socket head black oxide sheet metal screws with washers (front/rear panel)

1

External "wall-wart"/"brick" 12 VDC power supply, 120 or 240 VAC

1

IO3 3-input relay switching board

1

Ribbon cable, IO3 to LDR3x board

1

4-conductor cable, encoder to display module

1

Ribbon cable, display module to LDR3x board

1

Rotary encoder module with nut and washer

1

Master display board

1

Slave display board

1

Display module mounting bar (plastic angle)

4

Sets of nylon threaded rods with nuts & washers for the master display mounting bar

1

Ribbon cable, master to slave display module

1

USB cable, LDR3x board to rear panel

10 ft

White #24-26 gauge silver-coated copper wire (audio hookup)

1 ft

Red #20 gauge silver-coated copper wire (power hookup)

1 ft

Red #26 gauge silver-coated copper wire (trigger hookup)

1 ft

Black #20 gauge silver-coated copper wire (power hookup)

1 ft

Black #26 gauge silver-coated copper wire (trigger hookup)

3 ft

Green #20 gauge silver-coated copper wire (audio ground hookup)

1

0.060" x 5.7" x 8" FRP mounting board

6

#4 threaded hex stand-offs (mounting the LDR3x, input board, and ground bar)

12

#4 screws for the mounting stand-offs

2

#4 screws for mounting the display bar to the board

2

#4 nuts for mounting the display bar to the board

1

Apple remote

1

IR receiver module, to be soldered into the display module

Optional: 10 Cardas RCA jacks, and/or 10 ft of Neotech 26AWG UP-OCC solid copper wire, in place of the standard parts.

What you’ll need that isn’t included

  • Solder

  • Soldering iron

  • Allen wrench for socket head screws

  • Drill and drill bit, for the mounting sheet and mounting bar

  • Wire strippers

  • Wire cutters

  • Small screwdrivers (regular and Phillips) for screw terminals, encoder knob, etc.

A volt-ohm multimeter is recommended, though not strictly required.

Assembly instructions

Only rudimentary assembly instructions were ever published for this kit — prospective builders were encouraged to review what existed and judge for themselves whether they were comfortable taking it on at that level of documentation.

Available options

  • RCA jacks: upgrade to Cardas RCA jacks

  • Power supply: 120 VAC (domestic) — 12 VDC 0.5A linear regulated external "wall-wart," 2.1mm positive pin. 240 VAC (international) — 12 VDC 1.0A switching "brick" with detachable IEC cord and US AC plug, 2.1mm positive pin

  • Hookup wire: Neotech 26AWG UP-OCC solid copper