Element III Firmware Updates & Menu Options

Thank you to all first adopters of Element III! We’re glad so many of you are enjoying Element III as much as we are. While EL3 is temporarily sold out, we’ve been listening to all feedback to improve firmware features and overall quality (more coming in a separate post).

Most notably, Firmware v2.2.0 or newer allows customizing the Knob Button, and eliminates the need for a UAC1 Fallback cable when connecting to consoles.

Please see How to Install an XMOS Firmware Update. Element IIIs shipping after March 25th will arrive with the latest firmware preinstalled! This includes all EL3s shipping to retailers.

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Firmware Changelog

Version, Date	Notes
v2.5.2 07-21-2023	Resolved bug in cached treble/bass values when transitioning between output modes.
v2.5.1 06-13-2023	DSP Performance Updates Optimize DSP stages to achieve static-free PCM 352.8kHz and 384kHz support Adjust DoP detection state machine within DSP stages improve performance Corrected volume compensation for negative DSP gains Changed Treble DSP Frequency options to: [3k, 4k, 6k, 8k, 9k, 10k, 12k, 14k]
v2.5.0 05-31-2023	Added parametric bass and treble controls (2-band EQ)! Conditional DSP implemented in PCM audio path, using 1 dedicated core per biquad filter, dynamically configuring volume and gain for optimal listening. DSP filters are defeated by setting Bass Gain / Treble Gain = 0 Detect DSD/DoP streams within DSP threads to auto-bypass PCM filters in DSD mode Store separate EQ parameters for Headphone and RCA Output modes Reboot in rare event of 5+ serial resets (0 events observed in testing) Menu and UI improvements Support real-time DSP auditioning within the DSP menus Added submenus for UI, DSP, and DAC configurations Reduce menu entry long-press from 3 seconds to 2 seconds Changed default gain transition speed to “Aggressive” Display updates Differentiate between “DSD” (native) and “DoP” (DSD over PCM) streams Added “DSP ACTIVE” text when DSP is enabled for the current output
v2.3.2 02-14-2023	Full revamp of muting logic Fix: Ignore sampling rates changes of inactive input stream Fix: SPDIF mutes across gain changes when USB Muting is enabled Eliminate unnecessary mute writes to DAC Changed default value of “Mute Inactive USB = Enabled” Send I2C Stop Bit upon error and added reset count to status screen: Note zero events observed in 3000+ operation hours
v2.2.3 11-04-2022	Feature: Added “Mute Inactive USB” to options menu Added 15ms settling time after OLED init to increase I2C integrity
v2.2.0 03-25-2022	Added “Knob Button” to the options menu, configurable as: Toggle Input Toggle Output* Mute (USB only) Mute (SPDIF only) Added “USB Audio Class” to the options menu for UAC2/UAC1 selection Improved UAC1 descriptors to support Nintendo Switch Fix: Allow output mode changes while in the options menu. Improvement: Changed DAC synchronization rate from 100ms to 5ms to improve recovery time in case of ESD disruptions
v2.1.0 02-17-2022	Added “Auto Gain Speed” menu option with “Default” and “Aggressive” Moved Screen Timeout “Never” to end of selections Resolved issue that doesn’t clear rate during stream standby. Renamed options: “Encoder Steps” –> “Volume Steps” and “Encoder Resolution” –> “Knob Speed” Corrected S/PDIF De-emphasis behavior: Only apply de-emphasis if the S/PDIF stream indicates to do so and the current input mode is S/PDIF.
v2.0.9 01-31-2022	Initial Release

*Please Note: The Knob Button ‘Toggle Output’ option requires the latest bootloader, dated 14-Mar-2022. If you own an Element III from the first batch and wish to try this feature, please reach out and we’ll be glad to enable this capability for you. You may still install v2.2.0 on an Element III built prior to March 14th and the Toggle Output option will be hidden.

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Options Menu

Last updated June 2023

Pressing down on the Volume Knob for 3+ seconds enters the Options Menu. Turn the knob to navigate up/down the options menu. Push the center of the knob to make a selection.

Available settings are described below, with default values in bold.

UI SETTINGS

SCREEN TIMEOUT
Default: 5 seconds, with a range of 0 (never) to 120 seconds. We encourage a timeout for maximum OLED lifespan.

SCREEN CONTRAST

• • HIGH
  • MED
  • LOW

LED MODE

• • ON: LEDs will remain on while Element III is on.
  • WITH SCREEN: LEDs will power off while the screen is off.
  • 5 MIN STANDBY: LEDs operate as follows:

In S/PDIF mode, the LEDs will always remain on, as audio stream detection is available only in USB mode.
In USB mode, the LEDs will turn off after 5 minutes of audio inactivity. The LEDs will turn on:
(a) as soon as the USB stream becomes active again, or
(b) anytime the screen turns on with user interaction (which is true in any mode). When the screen turns off, the LEDs will turn off as well only if the USB stream has remained inactive for 5 minutes.
Consistent with 5 minute USB stream inactivity, the USB “rate” on the display will also be cleared once this standby limit is surpassed.
Note that the screen on/off is unrelated to the 5 minute standby setting. The screen power-off is related exclusively to the “Screen Timeout” option/setting.

The USB audio stream may be activated by any audio from your operating system. This feature has been tested under Win 10 and macOS. Behavior may vary with other operating systems. You can verify USB stream status in the “STATUS” menu.

KNOB SPEED

• • FULL
  • HALF

VOLUME STEPS

• • 0.5 dB
  • 1.0 dB

AUTO GAIN SPEED

• • DEFAULT:  A progress bar is shown as you reach the 0dB threshold, providing a few degrees of hysteresis.
  • AGGRESSIVE: No progress bar is shown. Transition between gain states is 4x faster at the 0dB threshold.

KNOB BUTTON
This option allows you to reconfigure the knob button to:

• • Toggle Input
  • Toggle Output [Requires 14-March-2022 bootloader]
  • Mute (USB only)
  • Mute (SPDIF only)

DSP Config (USB)

The following settings are available for each output mode, Headphone, and RCA/Line:

• • Bass Gain: -30 to +30dB
  • Bass Frequency: [40Hz, 60Hz, 80Hz, 100Hz, 110Hz, 125Hz, 150Hz, 170Hz]
  • Treble Gain: -30 to +30dB
  • Treble Frequency: [10kHz, 11kHz, 12kHz, 13kHz , 13.5 kHz, 14kHz, 14.5kHz, 15kHz]

Our custom algorithm uses subtractive equalization. You will notice an increase in the volume level readout when applying positive Bass/Treble Gain. This is the effective audio signal volume, and is guaranteed to be free of clipping. For example, if you typically listen at -30dB, you will probably find yourself listening around -20dB after applying 10dB of Bass.

DSP Implementation Notes:

• • DSP filters are defeated by setting Bass Gain and Treble Gain to 0. The display will present “DSP Active” when filters are enabled.
  • Stream support: PCM over USB (both UAC2 and UAC1). Filters are automatically bypassed when playing DSD or DoP audio.
  • Filter Type: Biquad, Q = 0.707
  • Latency: No observable impact. Each filter is processed within the USB buffer by a dedicated core.
  • THD: No audible impact. Observed SINAD remains within the margin of error with bass/treble enabled.

USB AUDIO CLASS

UAC2 is recommended for modern operating systems (Win 10/11, macOS, Linux, Android, iOS), providing ASIO support, DSD128 and PCM 32/384kHz playback, and ability to perform firmware updates.

Choose UAC1 to connect to legacy operating systems such as Win XP/7/8, Nintendo Switch, or PS 4/5. You may toggle between UAC2/UAC1 at any time. Element III will restart upon change, or prompt to restart. Alternatively, you may use a UAC1 Fallback cable in UAC2 mode.

MUTE INACTIVE USB

• Disabled: Preferred for Windows or macOS.
• Enabled: Preferred for Linux or Android to eliminate “alien sounds” while audio should be absent or otherwise muted.

DAC CONFIGURATION

2ND HARMONIC COMP
Default: 0, with a range of -75 to 75. Large values in either direction will increase second harmonics.

3RD HARMONIC COMP
Default: -20, with a range of -75 to 75. Large values in either direction will increase third harmonics.

DPLL BANDWIDTH
Default: 7, with a range of [0:15].
This setting directly impacts jitter rejection, with the optimal value dependent on timing stability of your PC or audio source. Most audio sources produce stable audio when DPLL is set to 5. We have conservatively increased the default DPLL value to 7 in order to support a wider range of sources, especially modern 4k TVs. If you encounter stuttering, try increasing DPLL Bandwidth.

SPDIF DE-EMPHASIS
Default: OFF. Setting de-emphasis to AUTO automatically enables de-emphasis when an incoming S/PDIF stream contains such a flag, and otherwise disables de-emphasis.

DAC FILTER

• • FAST ROLLOFF
  • SLOW ROLLOFF
  • MIN PHASE

STATUS
Displays the current firmware version, USB Stream status (Active, Inactive), and internally recovered I2C Errors. This information is intended for factory Q/C checking. Please note: I2C Errors can occur from strong ESD or other interference. Element III monitors for and automatically recovers from I2C errors. Over 17M transmissions occur every 24 hours, so it is normal to see an accumulation of I2C recoveries over time.

As of firmware v2.3.2, we also display the number of I2C bus “Reset” attempts. This number should remain at 0.

FACTORY RESET
As the name suggests, Factory Reset clears all above settings to their default states. Upon Reset, your Element 3 will default to -45 dB volume in Headphone Output mode via USB Input, and RCA Output will default to 0 dB.