This is a review and measurements of the SoundBlaster X-FI HD DAC/ADC and headphone amplifier. It is on kind loan from a member and it retails for USD $100 from Amazon with Prime shipping.The box itself is plastic but doesn't look too bad:The volume control is a rotary control of some sort with the worst feel positive. It is stiff with no notches and of course no indicators.Connectivity is good though with headphone and microphone inputs in front and line out/in plus phono input in the back. We also have our usual set of USB, S/PDIF and Toslink inputs.Plugging in the device into my Windows 10 did nothing so it is not UAC2 compliant. Went to get the driver and it is a 150 megabyte or so of what we used to call at Microsoft, "crapware." I used the custom install and disabled a bunch of stuff it wanted to install. Good news was that it also came with ASIO driver making it easier to test with my Audio Precision hardware.Let's get into the measurements and see what we have here.Since the X-FI HD has RCA out, I started by testing its DAC portion alone:Excessive harmonic distortion pushes the distortion specs to merely "OK." Reducing the digital level improved the situation by just a dB or two. Here is how the SINAD (signal over distortion and noise) rates compared to recently reviewed gear:It is at the bottom of tier 3 so nothing to get excited about.I jumped then to headphone output measuring its performance with a 300 ohm load:We start-off OK but then distortion sets in at just 1 milliwatt of power. Max power is a weak 13 milliwatts.Switching to 33 ohm load did not improve the picture:Distortion takes over now at just 0.1 milliwatts and max power before clipping is just 25 milliwatts.Worst news was still to come in the form of headphone output impedance:At 36 ohm, the frequency response and hence the balance of tones will be impacted by SoundBlaster X-FI HD. We like to see 1 ohm or lower here to avoid this effect.Instead of torturing myself or you all I decided to test the ADC but that was not meant to be. The Soundblaster driver reported that line in and microphone in were not operational. Selecting the ASIO driver as input just hug my Audio Precision software or did nothing useful. Oh well.Seems Creative is still sailing on the reputation of their PC audio products from decades back with no effort to produce a high-performance device. While the DAC portion is OK, the headphone output is a disaster. And who knows why the ADC doesn't work.Needless to say the pink panther is not happy and I can't recommend the SoundBlaster X-FI HD.------------As always, questions, comments, recommendations, etc. are welcome.Please considerfunds using: https://www.patreon.com/audiosciencereview ), or https://audiosciencereview.com/foru...eview-and-measurements.2164/page-3#post-59054 ).