Battery Power Supply
Those who also know my other reviews in these pages, know that I love my BPS'ses. My Jef Rowland preamps and poweramps alike, all have Battery Power Supplies. BPSes can sure bring many advantages but it's not always better in all areas. For example, switching the Rowland amps to pure battery operation makes for a super-smooth and un-electronical, relaxed and very freely floating soundstage but at the expense of some speed and drive in the bass. I just switch on and off the BPSes depending on my mood.
So how does the UD10.1 Lite perform with batteries? The manual clearly states to bve careful with this. Before connecting an external power supply (and I suppose the battery pack counts as that) you need to unplug the USB cable. Otherwise the Burr Brown converter might get damaged. To me, this sounds strange. Couldn't they have implemented a safety circuit inside? I mean, these kinds of mistakes are all too easy to make. Maybe that's a cost consideration, who knows. But I wasn't about to make this mistake of course. After unplugging the USB cable, I plugged in the batteries and switched them on. Nothing happened. Then I inserted the USB cable. Again nothing happened. Quickly I unplugged the USB cable and measured the batteries. Indeed, they had been depleted. A measly 2,7 volts were available. I just assumed that they had been fully charged but you know what they say about assumption... So, I charged the batteries with the supplied charger but since I would have to wait for them to be charged, I resumed testing, with an AC adapter this time.
External adapter instead of USB Bus power
An external power supply wasn't in the package (there's an optional PW-10 for that) but I dug up a linear 350mA 5 volt power supply. After unplugging the USB cable and plugging in the powersupply, the blue led comes on. So far so good. But after inserting the USB cable, the UD10.1 just isn't recognised in Windows anymore. Unplugging the USB cable and powersupply and reinserting only the USB cable it works again. I tried it three times, with longer waiting times but I had no luch with this external power supply. I measured its output and lo and behold: the specified 5 volts turned out to be 9,7 volts! This was one seriously mislabelled power supply! I then dug a little deeper and found a bunch of other power supplies. Not wanting to take any more risks I chose a regulated universal supply. Its 4,5 and 6 volt settings came closest to the preferred 5 volts. I checked the polarity and measured its output and the specified 4,5 volts turned out to be 5,1 volts. Perfect! This time, the external power supply did work. It made for a smoother sound with less dryness and more subtlety. Now it started to sound like music! But before I could start enjoying myself, the sound switched off. And on again. And off again. Now I bacame paranoid and quickly checked the UD10.1 with USB power. That still worked. Then I tried another powersupply, again a universal stabilised version with 5 volts output. But the same happened. Would I have damaged the device with the 9,7 volts of that first wrong powersupply? Surely a few seconds should be sustainable? Or would it be an interaction between my USB port and the power supply?
Analog line out
While waiting for the batteries to be charged I proceeded to listening to the built in DAC and its analog output. At first I wanted to compare its output by means of headphones but my PC has no headphone output. Only a built in RealTek HD line out. So I compared the two line outputs using my Harman Kardon GLA55 active speakers. There is a hige difference between these two outputs. While the built in Realtek output is very smooth and gentle, it is also very undynamic and lacks drive and speed. The Trends UD10 in comparison sounds very lively, dynamic and more enthusiastic. But it is also a little less refined and can sound slightly rough. Which sounds better overall is totally up to you, your setup and your taste. I would choose the Realtek output since the Harman Kardon speakers are already very lively and forward and they can use a little softening. When connected to more balanced speakers the situation is entirely different and it becomes clear that the Realtek output is just way too smooth for its own good, masking rhythm and dynamics and blurring pace. Even for me it is too smooth. And I like smooth!