In the upstairs room, I added DDC to DAC, the first on its wall wart, the second on the Clean Power. An HDMI cable between them exploited their proprietary I²S path. Rotating the clock generator from x 1 to x 2, x 4, PCM and finally DSD correctly triggered the DAC's color-coded indicator from red to green to blue to purple to yellow. With a PCM input, the PCM position upsamples all to 32/384. It resamples DSD64 to 96kHz, 128 to 192kHz, 256 to 384kHz. The DSD position doesn't touch DSD. It only converts 44.1-96kHz to DSD64, 176.4/192kHz to 128, 352.8/384kHz to 256. In the next shot, I overlaid the X7-DAC's display of DXD (purple) onto DSD (the yellow light left of the 6.3mm port which would be accompanied by a yellow logo). The DDC's red light signifies incoming 44.1kHz data. The battery supply's green means it was fully charged. The upshot? When engaging this clock generator, one upsamples Redbook rates asynchronously. 44.1kHz becomes 96 not 88.2kHz; etc. If you prefer power-of-two rates, use a software-based upsampler, then set the JAVS to x 1 to bypass its ASRC. This is a very flexible device.

Here we see my first system: Soundaware A280 SD card transport and Bakoon AMP-13R below foot stool, Nagra Classic Preamp and JAVS stack atop. Speakers were the sound|kaos Vox 3a enhanced with the mechanical low-pass filter from LessLoss called Firewall for Loudspeakers. A Zu Submission subwoofer in the left front corner added some faint assist with a 4th-order low pass at 20Hz, boost of +6dB/20Hz.

With instant sound, I left the room to let the X7-DDC Femto warm up and do a few 24/7 rounds by itself.

After ten days and when the sound|kaos speaker review had finished, I started to pay close attention. One initially simpler track I picked for very exposed vocals and clear uncomplicated accompaniment was this lovely number by Eda Karaytug. My digital cable was a Chris Sommovigo Tombo Trøn coax. It went either into the DAC to bypass the DDC; or into the DDC which then wired to the DAC via HDMI. Here I found different clock rates very subtle beyond feeling that my least favorite was DSD resampling and that, perhaps, I fancied x 1 the most. But adding/subtracting the DDC wasn't this subtle. Before I describe the difference, let's detour very briefly into… yes, salt.

Have you experimented with reduced or zero salt intake? Then you might remember a transition. At first, not using salt made the food taste bland. Once taste buds recalibrated, the food's subtler flavors emerged which the salt had overpowered. Living salt-less for a while then going back showed how salt acts as a stimulant. It desensitizes us to finer flavors. Now we leave the food kitchen for the hifi spice rack. With the DDC, Eda's voice sounded smoother, the intro's subtle qanun quivers rose more defined against silence. That's higher contrast ratio. The effect is stronger image pop. It's most easily noticed on simple fare with lots of silent gaps between/around tones. Smoothness is a subtraction of subliminal grit. If our ear buds aren't already hip to it, this can telegraph as less salt. Greater smoothness can feel more bland. It lacks a certain edge or salty aggression. If that's the reaction, live without salt for a while. Nearly invariably, re-injecting its edge afterwards exposes its hifi version as an unnatural thing. It's a kind of crystalline rust. It interferes with the natural flavor of recorded instruments and voices. And… if you simply prefer more salt, there's no rule which says that you can't enjoy that instead. Having and voicing a hifi is all about pleasing yourself!

Having surprised myself for hearing this difference even on a low-jitter SD card source, the next stop was the max-res headfi system with Auralic's first Vega DAC.