Revision 1.1 - August 24, 2015 


Geek Out is a high performance portable USB digital-to-analog converter (DAC) and headphone amplifier. It has been designed to decode almost any music file format and resolution available, up to and including Direct-Stream Digital (DSD).

The Geek Out accepts digital audio signals through USB; and it will output audio signals via two 1/8” single-ended TRS headphone jacks.

When used in conjunction with the appropriate playback software, the Geek Out supports PCM sample rates of 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, 176.4 kHz, 192 kHz, 352.8 kHz, and 384 kHz in 16, 24, and 32-bit depths. Geek Out also supports native 1-bit DSD64 and DSD128, as well as DSD-over-PCM (DoP).

This document provides the steps necessary to connect the Geek Out to a computer, and configure it as the default audio output device.

Getting Started

  1. USB Port Connector
  2. Audio Format Indicator
  3. Sample Rate Indicator
  4. TCM Digital Filter
  5. FRM Digital Filter
  6. 0.47 Ohm 1/8" TRS Headphone Jack
  7. 47 Ohm 1/8" TRS Headphone/Line Out Jack



  1. Unbox the Geek Out and remove it from the plastic wrap.
  2. Connect the Geek Out to a USB port on the computer (without headphones or any other external components connected/powered on).
  3. If using with a Mac OS X or Linux computer, no drivers are required. However, if a Windows PC is being used, download and install the Light Harmonic Audio Driver. found here
  4. A quick step by step guide for installing the driver can be found in the Geek Out Driver Installation page




In order for the computer to play sound through the Geek Out, the Geek Out must be set as the default audio output device.





After installing the Light Harmonic Audio Driver and Light Harmonic Control Panel, continue to follow the steps in the Light Harmonic Audio Driver Setup Guide to set the Windows Default Sound Output to the Geek Out.


Mac OS X


In OS X, go to the Apple menu at the top left of the screen, and open System Preferences…



Click on Sound and select Geek Out HD Audio 1V5 as the audio output device.


Using The Geek Out



When the Geek Out is plugged into the computer there may be a popping noise sent through the headphone/line out outputs. This is caused by the power caps in the signal chain charging. This is a conscious design decision to not add a buffer as it would affect the sound quality.


It is recommended that the Geek Out be left connected/powered on at all times as it will keep the components warm, providing the optimal sound quality. However, if the Geek Out needs to be disconnected/reconnected, be sure to unplug headphones and/or power down the preamp/amp/active speakers to avoid any potential damage.


LH Labs will not be held responsible for any damage to equipment due to this design implementation.




Volume Adjustment


When using version 1.5 of the Geek Out firmware, volume is controlled from the computer/application audio controls.


NOTE: If version 1.0 of the Geek Out firmware is being used, the buttons on the side of the Geek out will control the volume. However, it is highly recommended the firmware be upgraded to version 1.5 to fix issues in 1.0, the worst being unexpected volume spikes that could potentially damage equipment or hearing.


Digital Filter


Digital filters are used to remove artifacts in the digital signal caused by audio sampling. The Geek Out offers the following filters:


TCM (Time Coherence Mode) – Uses LH Labs minimum phase digital filter and time optimization algorithm which removes all post ring from the original signal, and realigns the impulse response. This presents the listener with a more well-defined and natural soundstage.


FRM (Frequency Response Mode) – Uses LH Labs slow roll-off linear digital filter and frequency domain optimization algorithm to provide a smoother and clearer sound with even lower THD+N.

Headphone outputs can be found on the opposite end of the USB plug on your Geek Out. There is one 3.5mm of .47 Ohms used for Headphones and one 3.5mm 47 Ohms used as a line out of Audio equipment, or bigger Headphones with a higher impedance. The top button (closest to the computer) is the TCM filter, with the bottom button being the FRM filter.

The top 2 LEDs (out of the 3 on top) will light up when TCM is engaged, and the bottom 3 LEDs (out of the 4 on the bottom) will light up when FRM is engaged.

Please note, after a few seconds the LEDs will revert to show the audio format/sample rate of the current/previous audio file playing.

Geek Out Firmware Upgrade

From time to time newer versions of the Geek Out firmware will be released to fix bugs, and/or add functionality. The Device Firmware Upgrade (DFU) utility will need to be used to complete the upgrade.



As of this writing (February 2015), the Geek Out firmware can only be upgraded from a Windows computer that has the Light Harmonic Audio Driver installed. The Light Harmonic DFU utility is installed on the computer as part of that process.


The Light Harmonic DFU utility for Mac is currently in development, but because of operational issues beyond our control, it is currently not available for distribution.




Getting Started

In order to perform the firmware upgrade, the newest version of the firmware will need to be downloaded from here.

Click the Firmware v1.5 link to download the file. Be sure to save it to a familiar location, such as the computer Desktop.

File Extraction

The Geek_Out_Firmware_1V5 zip file should now be visible at the saved location. The file will need to be extracted (unzipped) prior to use.

Right-click the file and the context menu will appear. Select Extract All… from the list of options.

A dialog box asking where to save the extracted files will appear. Click Extract to select the default location. Keep “Show extracted files when complete” checked.


When complete, the Geek_Out_Firmware_1V5 bin file will be present in the extraction folder.


Light Harmonic Device Firmware Upgrade (DFU) Utility


To upgrade the Geek Out firmware, the Light Harmonic DFU utility will need to be on the computer (it is installed along with the Light Harmonic Audio Driver).


The Light Harmonic DFU utility is installed to the following location by default:


Local Disk (C:) – Program Files – Light Harmonic – USB_Audio_Driver



Double-click the LightHarmonicDfu file to open the utility (the Geek Out must be connected). The utility interface is shown below:



Click the Browse… button to locate the Geek_Out_Firmware_1V5 bin file. Select the bin file and click Open.



The bin file location will be displayed in the Firmware box, and messages that the device is opened and ready for firmware update will be displayed in the Upgrade box.



Click the Start button to begin the upgrade process. A progress bar will be displayed.


Once the firmware upgrade is complete a message will be displayed that the firmware is being started, and that the firmware upgrade finished successfully.


After the upgrade is complete, close the utility, and disconnect the Geek Out.


After 10 seconds, reconnect the Geek Out. Be sure to test that the Geek Out plays back audio and is free of any bugs that may have been present previously.



If there are any issues completing any of the steps in this document, understanding any of the concepts, or with audio playback, please open a support ticket through the LH Labs support page at: