Disclaimer: Audient Japan loaned me the iD4 for the purposes of a headfonia review. The iD4 is their newest, most compact, and affordable ADC/DAC for recording and monitoring. It goes for about 299$ USD. You can find out all about it here: Audient iD4.
Adjusting input levels, and volume is easy breezy thanks to fine-tuned DAW and plug-in controls. Its headphone amp being poorly suited to low-resistance earphones, returning anomalies in frequency response, THD, IMD, and stereo crosstalk. Most of the anomalies smooth out by the time portable or monitoring headphones are plugged in. And, iD4 spits perfectly matched volume into both channels at all volume levels, not to mention trace amounts of background noise. I’ve yet to go deep into its microphone amps, but after digitising test signals from Mojo, I am relatively convinced of its recording fidelity - considering its price, and ostensible market. Stereo crosstalk numbers aside, that is.
The iD4’s controls are well laid out, solidly installed, and precisely labelled. The front instrument input boasts a great gain stage, and records in stereo to boot. Considering its price, it is ridiculously solid. And while I’m not a big fan of USB audio, the iD4 is rock solid on OSX (where it is also plug-and-play), powerful, and embarrassing to devices that just a few years ago occupied the same price bracket. Despite a somewhat poor showing from its headphone amp, I’m impressed.
Note: Because I don’t have a powered USB hub, I can’t test the iD4 with an iPhone, which typically nets the best USB performance of any device I own. RMAA noted significant performance differences between my 2012 iMac, and my 2015 MacBook Pro, which meets my expectations. Very few USB devices perform well through the iMac. Mojo - yes, god itself - is one.
The following Rightmark Audio Analyzer tests were conducted through this equipment.
Source: Audient iD4
ADC: Lynx Studio HILO LT-TB
Computer: MacBook Pro 21015; 2012 27" iMac
Cables: 1,5m Hosa Pro 3,5mm stereo to dual 3-pin XLR (around 8$)
Loads:
NL - no load
SM2 - Earsonics SM2
S7 - Audio Technica ES7
DT880 - Beyerdynamic DT880
24-bit TARGETS and loads (+6dB)
24-bit summary (+6dB)
D.I summary (+6dB)
End words
While I’ve got a few weeks to suss out as many features as possible, it’s fair to say that the iD4 is a far better recording system than it is a headphone amp, though for monitoring headphones, it should be as good as is necessary. And, its near-field powered speaker outputs run a reliable signal out back. Because its headphone outputs are so damn low noise, it is even more a shame that its headphone output can't reliably drive earphones. However, that's a small knock for a device targeting home recording, podcasters, and engineers away from their studio.