Amplifiers and DACs can be found in all kinds of shapes and sizes, but the HiFiGo THX Onyx is one of the smallest and most compact we've ever seen to be perfect for traveling audiophiles. The manufacturer sent us a sample for our honest impressions and, for most users, the tiny Onyx is likely going to impress no matter the setup.
At its most basic level, the Onyx is a USB-C to 3.5 mm audio jack adapter for PCs, Macs, Android, and iOS devices. Calling it a simple adapter would be a disservice to the product, however, as it integrates an ESS Sabre ES9281PRO DAC for audio processing, decoding, and automatic rendering at up to MQA quality should it detect an MQA source. It's all plug-and-play with no software or outside drivers required.
LED Status Indicators | Sample Rate | Audio Description |
Blue | 44.1 or 48 kHz PCM | Standard Quality |
Yellow | >48 kHz PCM | High Resolution |
Red | DSD | Direct Stream Digital |
Magenta | MQA Render | Master Quality Authenticated |
To test the effectiveness of the USB-powered amp, we connected it to our Microsoft Surface laptop via USB-C and then our Audeze LCD-1 Planar headset via the 3.5 mm jack. Then, we put our Earthworks M23R microphone between the headphone cups as shown by the picture above to record pink noise at maximum volume. The recordings would be done first with the headset connected to the THX amp and then with the headset connected directly to the Surface laptop without the amp. If the THX amp is doing its job, then maximum volume should be louder with the dongle than without it.
We're able to measure dB(A) readings of 87.1 without the amp and 94.7 with the amp to represent a significant increase in maximum volume through the passive THX Onyx solution. The pink noise curve also shows improvements in both the subwoofer and higher 8K frequency ranges with no major static or noise.
There are a couple of things we would change about the Onyx. Its 3 LED indicators, for example, will flash in many different sequences and colors that can be easy to forget what they all mean without referring back to the manual. Furthermore, the adapter itself is still somewhat large when connected to a smartphone or tablet which makes it not as pocket friendly as it could have been.
The THX Onyx is now available on Amazon for $199 USD.