As display and audio technologies move to ever more complex and higher resolution systems (4K, UHD, HDR, Dolby ATMOS etc.), the processing requirements can easily cause AV synchronisation issues. In addition, each component change, software, or firmware update has the potential to alter the AV sync in a system.  Watching content with poor AV sync is one of the most annoying and complained about problems.

Sync-One2 accurately measures the time span between an audio beep and video flash (e.g. a 2-pop / flash frame or similar, Sync-One2 specific test files are available for download), clearly displaying the delay and if the audio leads or lags with reference to the video.  The error is displayed in milliseconds (1/1000th of a second) and, if desired, also in frames, in real-time.   You may also enable a running average to average potentially 1000's of readings, and again this is displayed in milliseconds or frames.  Statistics are calculated on the most recent readings taken to help check overall system stability or drift, including the average and span of the readings.

Sync-One2 will work with any resolution or type of display, so it is 4K / UHD / HDR-ready, fine with LCD, OLED, Plasma, and Projectors.

Sync-One2 has the following core features.

  • Simple one-handed operation, turn on Sync-One2, and it's ready to go
  • Easy to read OLED display
  • External audio input via a 3.5mm audio jack
  • A simple menu system is used to adjust settings and set options
  • Settings and options stored in flash memory so retained even if the batteries are removed, although the memory buffer is cleared at shutdown
  • Self-calibrating to help reduce false readings from ambient light and noise
  • Additional support for testing in spaces with long reverberation times
  • Real-time output in milliseconds/frames, You can also display a rolling real time average in milliseconds or frames
  • Fast startup, ready to take measurements in just a few seconds
  • USB Mini-B port for data logging, an API to enable remote control, and to supply power
  • The ability to add a custom startup splash text, this is a user setup or can be ordered with permanent startup splash text
  • Firmware upgradeable for new features and bespoke customisation


  • Internal microphone for audio pickup.
  • 3.5mm stereo (downmixed to mono internally) audio jack for connection to headphones or line out as a direct audio feed.  Supports up to 3v RMS (9v peak to peak) maximum line input.
  • External audio detection is automatic but may be overruled via a menu option.


  • Measurement of audio visual delay up to ±750 milliseconds (±3000 milliseconds in extended mode).
  • The display is rounded to the nearest 1 millisecond or 1/100th of a frame, internal timing resolution of 0.01 milliseconds.  The minimum resolution between a light and sound pulse is 0.05 milliseconds.
  • Self-calibration adjusts for ambient noise and light, including fluorescent/ LED light flicker.
  • Automatic microphone gain adjustment during the calibration process.
  • Adjustable audio trigger level (default is high sensitivity).
  • Adjustable video trigger level (default is high sensitivity).
  • Adjustable Mask Time (the minimum time before Sync-One2 re-arms for the next reading) to help with spaces with long reverberation times.


  • Dimensions (H x W x D), 144mm x 90mm x 30mm (5.6" x 3.5" x 1.2”).
  • 165g (5.8oz) excluding batteries.
  • 16 x 2 OLED display for easy viewing, fast response, and low power consumption.
  • Operating temperature from 5 to 50 Celsius (41 to 122 Fahrenheit).
  • System firmware is upgradeable to enable upgrades for new features or bespoke customer requirements.
  • The ability to add a custom splash text message on startup.
  • The ability to order Sync-One2 v2 with a permanent splash text message, so it's easy for companies to add a brand or bespoke identification.


  • 2 x AA (LR6) batteries, rechargeable AA batteries are fine too.
  • Reverse battery protection.
  • Battery life from standard AA batteries is around 50 hours of continuous operation.
  • A tiny current of less than 0.1 µA is used when off. Therefore, when not being used for a while, it is always best to remove the batteries.
  • Low battery indication and auto shutdown when batteries become too low to maintain accuracy.
  • It can be powered via the USB Mini-B port with or without batteries fitted.

Data logging and API interface

  • Via the USB Mini-B port, real-time logging of readings.
  • An API interface enables remote control of Sync-One2 v2 to automate testing/system adjustments or gather data for system compliance reporting.
  • A separate manual contains the API commands available.

Made in the UK

Compliance to standards

CE Mark

EN 55103-1:2009 Part 1 (EMC Emissions)
EN 55103-2:2009 Part 2 (EMC Immunity)
EN 55103-2:2009 (Magnetic Immunity)
IEC 61000-4-2 (ESD)

RoHS compliant and lead free