V4 board with LDR module installed - horizontal view
OLED display assembly front view with cabling and encoder
quad ldr module2 - side view
Apple remote alternative | the "Function" remote
solid state buffer module - without LDR mdoule
V4 board with LDR module installed - horizontal view
OLED display assembly front view with cabling and encoder
quad ldr module2 - side view
Apple remote alternative | the "Function" remote
solid state buffer module - without LDR mdoule

$523.00

ePot.V4 bundle

$523.00

The ePot.V4 is an LDR attenuator and preamp controller, that together with our OLED display module and infrared remote, enables you to build a  full featured, remote controlled passive preamplifier, and when equipped with an optional solid state buffer board, can functions as an active preamplifier.

Like all Tortuga Audio preamp controllers, the V4 employs light dependent resistors (LDRs) as the sole means for for audio attenuation (volume control). No mechanical potentiometers or switched mechanical attenuators are used.

The V4 represents the 5th generation of Tortuga Audio LDR based passive preamp attenuator and controller and builds on work that began over 15 years ago.

The V4 is available to both DIY audio enthusiasts and audio OEMs. 

Looking for just a V4 board and not a complete bundle?

The V4 can be purchased by itself, both with and without an LDR module and/or a remote. Check out the ePot.V4 by itself.

The V4 “bundle”

The V4 bundle combines all the V4 series components we offer into a single convenient discounted package. The bundle is a collection of parts we make and/or sell but does not represent a comprehensive kit. You can purchase all these parts separately or together as a bundle for a 15% discount.

A bundle comes in 2 flavors, passive and active. The passive version is simply the ePot.V4 system as its default self. The active version is identical except for the addition of a SSBM.V4 solid state buffer module that mounts directly to the V4 board itself. The SSB.V4 buffer board turns the passive V4 into direct coupled active preamp with optional gain.

What’s included?

The following items are included with each V4 bundle:

  • A fully functional V4 board that has been calibrated
  • Power cabling to the V4 board
  • 4 sets of mounting standoffs with screws
  • Quad LDR module installed, tested, and calibrated
  • Optional SSBM.V4 solid state buffer module for active version tested and installed
  • OLED display assembly including encoder, IR receiver, and cabling

Each of the components in a V4 bundle are listed below along with links to their individual product page. You can buy the bundle at a discount, or buy any component individually.

Each item in the bundle is listed below together with links that will take you to each product’s listing.

ePot.V4 attenuator & preamp controller

V4 board with LDR module installed - horizontal view
V4 preamp controller LDR module install diagram
quad ldr module2 - side view
Apple remote alternative | the "Function" remote
V4 board with LDR module installed - horizontal view
V4 preamp controller LDR module install diagram
quad ldr module2 - side view
Apple remote alternative | the "Function" remote

The ePot.V4 is an LDR attenuator and preamp controller, that together with our OLED display module and infrared remote, enables you to build a  full featured, remote controlled passive preamplifier, and when equipped with an optional solid state buffer board, can functions as an active preamplifier.

Like all Tortuga Audio preamp controllers, the V4 employs light dependent resistors (LDRs) as the sole means for for audio attenuation (volume control). No mechanical potentiometers or switched mechanical attenuators are used.

The V4 represents the 5th generation of Tortuga Audio LDR based passive preamp attenuator and controller and builds on work that began over 15 years ago.

The V4 is available to both DIY audio enthusiasts and audio OEMs. 


Quad LDR module

quad ldr module2 - top view
quad ldr module2 - side view
quad ldr module 2 - end view
quad ldr module2 - top view
quad ldr module2 - side view
quad ldr module 2 - end view

The quad plug-in LDR module holds 2 pairs of LDRs where each pair represents a separate audio channel. The LDR pairs act as voltage dividers for controlling volume. Every V3 and V4 series preamp controller board requires a quad LDR module and is usually purchased  as part of a new controller board but can also be purchased separately here. 


Solid state buffer module | SSBM.V4

ePotPi.V4 Rev B buffer board prototype pcb
solid state buffer module - without LDR mdoule
V4 preamp board with solid state buffer module - right side view
ePotPi.V4 Rev B buffer board prototype pcb
solid state buffer module - without LDR mdoule
V4 preamp board with solid state buffer module - right side view

The SSBM.V4 is an optional add-on active buffer board for the ePot.V4 LDR preamp attenuator/controller. A buffer typical acts a high impedance firewall between the output of a volume control and an amplifier. A buffer is more of a current/power amplifier than it is volume amplifier. A buffer doesn’t make audio sound louder, it makes it sound as energetic and dynamic as it was when originally recorded. 

The SSB<.V4 is a direct coupled buffer with high input impedance, low output impedance, and adjustable gain with default set at unity (no gain). It plugs directly into the V4 board and benefits from a high quality 5 volt power supply. 


OLED display assembly

OLED display assembly front view with cabling and encoder
OLED display assembly with encoder attached
EastRising OLED display dimensions
OLED display assembly front view with cabling and encoder
OLED display assembly with encoder attached
EastRising OLED display dimensions

The OLED display assembly is a 256 x 64 pixel, high contrast white-on-black graphic OLED (Organic Light Emitting Diode) display for use with Tortuga Audio’s preamp controllers and related Tortuga Audio preamps.

The OLED display assembly provides an easy and intuitive user control experience through an interactive menu driven control interface designed around a 7-button Apple or compatible remotes. 

The display assembly includes a custom adapter board with installed infrared (IR) receiver module and a header for connecting an encoder module. All cabling is included. The unit is fully tested and ready to go and requires no assembly per se.

Please note however that NO mounting hardware is included and is entirely up the buyer.


Function remote control

Apple remote alternative | the "Function" remote

We adopted the Function remote to replace the silver Apple remote that is no longer in production. The Function remote is an infrared type remote. It’s easy to use, is well constructed, has a high quality feel, and is very responsive. The Function remote currently works only with the V4 series controllers and preamps.  


What’s NOT included that you’ll need?

The following items are not provided but are typically required to have a fully functioning V4 system:

  • RCA and/or XLR audio jacks and sockets for connecting audio signals to the V4 board
  • A 5 volt power supply rated at least 1 amp. You can probably get away with a 0.5 amp power supply but we recommend 1 amp.
  • Some type of enclosure or plinth to which you can mount all the V4 hardware

V4 manuals

The online product documentation system (“Docs”) has 2 manuals for the V4; an operations and control manual and a hardware manual. Each are discussed briefly below.

This manual describes the how to operate the V4 via infrared remote, local rotary encoder, together with its menu driven OLED display .

This manual describes the design basis, hardware features and interfaces of the ePot.V4 Max (“V4” or “Max”  ) LDR stepped attenuator & preamp controller.