fallingreason
500+ Head-Fier
- Joined
- Sep 9, 2009
- Posts
- 776
- Likes
- 22
uDSD Review
Build Quality and Design: The build quality is excellent. The chassis/casing is overall similar to the NuForce uDAC units, but the finish is much nicer. The contrasting bright silver logo is a nice design touch. The RCA jacks are of higher quality than the uDAC units. In fact, they are nearly identical to those used on my CEntrance DACmini, and by memory the HDP. This immediately let’s me know that the device’s line level output signal is to be taken seriously. The weight of the unit is nearly twice that of the uDAC two, as is the depth of the unit’s dimensions. (all details can be found at http://nuprimeaudio.com/index.php/product/dac-headphone-amps/portable-dacs/udsd) The volume knob feels as I would expect for a portable unit. Though, the knob/pot interface is not as snug as on my uDAC2, there is a tiny bit of slack. This may be able to be tightened internally but I did not open the unit.
The USB-A input is upside down compared to other devices I have with the same input, and the RCA output is backwards from what I am used to. (R is on left and L is on right) Unusual, but does not cause problems.
Equipment used for review listening:
NuForce uDAC2
NuPrime uDSD
CEntrance DACmini
Sennheiser HD700
Westone 3
JH Audio JH5
Tweak City Audio 2-way bookshelf monitors + Tweak City Audio Gizmo amplifier.
NuForce Impulse USB Cable - 1 foot/0.33m
In addition to testing performance as a USB powered DAC/Amp combo, the RCA output of the uDSD is 2V and was fed to my DACmini for comparing DACs using the DACmini’s class A amplifier, and to a stereo amplifier for 2-channel listening.
I used exclusively the PCM decoding as I am not fully on board with thinking DSD will provide better sound.
I did not test the Coaxial bridge ability.
Sound:
The first thing that I need to say about the sound is that, if you are not using a powered USB hub, you will not be hearing the best sound the uDSD can put out. I personally used the Juiced Systems 6+1+1 USB3.0/Ethernet hub. While not a dedicated USB power isolater for audio components like the Shiit Wyrd, it is a high quality USB hub and was very effective and cleaning up the sound as well as greatly increasing the headphone amplifier power.
Headphone Amp: The headphone amp drives my IEM’s fine, but it was not capable of driving my 150ohm load HD700’s. I’m sure it would be fine for many lower impedance (<100ohm) headphones, such as Denon models. On my uDAC2 I am only able to turn the volume knob about 1/4 of the way up before my Westone 3’s are plenty loud. The uDSD volume knob must be turned up at least half way while not powered by an external USB hub, but about one-quarter turn with a powered hub. The tracking may not be linear and the total power output capabilities may be similar between the two, but the uDSD amplifier sounds cleaner overall. However, it is impossible to compare the two amplifiers while using the same DAC. I will also note that the volume tracking is very balanced between L/R channels on the uDSD down to very low volumes with my IEM’s, even better than the uDAC 2 with the TOCOS pot. Because I primarily use IEM’s with USB powered DAC’s, I prefer the amp and volume control of the uDSD due to larger usable range of the volume pot, allowing for finer control.
Sound Signature: It is apparent that the uDSD is a departure from the NuForce house sound. The uDSD is not as bright as the uDAC 2 or the HDP. Upon first listen, vocals and the midrange are much fuller and the highs are smoother. This was consistent throughout my comparisons. The smooth highs do not necessarily sound rolled off, but there is not as sharp of an attack with higher frequency notes. This tends to make me infer there would be less sibilance, but I did not listen to any source material that I have ever encountered sibilance issues with. This makes for a sound that is much easier to listen to for extended periods. The bass is also punchier, with more definition, and with better sub-bass than the uDAC2’s. The uDSD has a “higher gain” sound than the uDAC 2, though not necessarily the HDP. Micro-detail is not something that is brought out by the uDSD. The HDP was better in this regard, but with a bit more fatiguing sound character as well.
Treble:
Treble on the uDSD is what I would describe as “nice”. It does not draw too much attention to itself, is nicely extended, but does not ever poke its head out in front of other parts of the spectrum. It is much improved over the uDAC 2 and nearly as good as my DACmini in that it is nicely resolved and cohesive with the entire sound.
Midrange: Much fuller and with more resolution than the uDAC2. While listening to tracks with acoustic guitar strumming, the uDSD was not quite as resolving as the DACmini, but extremely good in its own right and leaps and bounds better than the uDAC2. Vocals were amazing and with fairly good transparency. I actually feel the midrange is slightly forward on this unit, which I like a lot. It may not have the micro articulations and texture that you will hear in high end DACs, but I never felt deprived while using the uDSD. For critical listening with the HD700’s or even 6xx’s and similar quality cans, one may (or may not) appreciate the next tier of source equipment.
Bass: Bass has good weight and definition. Fast bass lines have markedly better separation than the uDAC 2, but with less texture and depth than my DACmini. I often can first tell differences in performance between DACs by the bass, and the fact that this immediately jumped out at me as an area of such clear improvement from the uDAC 2 was a quick eye opener.
Headstage: The uDAC2 unit hits you with a wall of energetic sound, with little to no depth versus the uDSD. The uDSD smoothes the edges, calms down the presentation, and improves on the resolution with a deeper and wider headstage. The headstage is near that of the HDP.
Final Impression:
The uDSD may likely be my go-to portable DAC for listening to stereo loudspeakers in my home. The DAC is good enough to put out what I desire for room-filling sound. As a budget desktop amp, it also performs admirably when compared to my DACmini, especially when paired with a higher powered amplifier for harder to drive full-size headphones. The small footprint scores big points for me, which is a reason I like the design of NuForce products, and the DACmini. I do notice a definite difference between this unit and higher end DAC's which is to be expected as this is still within the USB powered range of equipment. However, this unit will allow many listeners to build a complete setup for full-size headphones that quite affordable, or place a very high quality DAC nearly anywhere in their home for any USB application.
Is the price of the uDSD worth it? Hands-down yes. And an amazing deal with the current trade-in rebate program. I would think of it as a great portable DAC, with a pretty decent built-in headphone amplifier as a bonus
Definitely one of the current top contenders in the sub $200 range.
