NuForce is a major reference as far as top-of-the-range hi-fi is concerned, particularly when speaking of DACs and digital amplifiers. The NuForce Icon DAC we are reviewing today is a hybrid device, both USB Audio DAC 32 bits / 96 kHz and headphone amplifier. It is also one of the most powerful on the market, able to deliver 1.2 W at 16 Ohms and 126 mW at 600 Ohms. In other words, no matter what kind of headphones you are using, you will obtain a high sound level with the NuForce Icon DAC.
The NuForce Icon DAC is fitted with a type-B asynchronous USB port, two stereo analog inputs ? one 3.5 mm mini-jack and one RCA ? a stereo RCA analog output, a coaxial S/PDIF RCA digital output and a Neutrik jack 6.3 mm headphone output placed on the front panel. Two potentiometers on the front panel allow you to switch the device on and to adjust the sound level as well as choosing a digital or analog input.
Packaged like a high-tech device, the Icon DAC comes with its power supply block and a type A-B 1.5 m USB cable, as well as a white translucent silicone support base. This anti-skid base allows you to place the Icon DAC vertically in a particularly secure way. This system provides easier access to the volume potentiometer and stabilises the Icon DAC. The only slight drawback is that we would have liked a 3.5 mm mini-jack to 6.3 mm jack adapter.
Isn’t it self-powered’
No, the NuForce Icon DAC is not self-powered via its USB port, but comes with its dedicated power supply. This is, in our opinion, a really good thing. USB powering, although convenient for a tablet, is limited in terms of power and depends on the quality of the computer’s motherboard. The power stability is rarely good. There are some excellent self-powered DACs but a dedicated power supply is always a plus with the possibility of switching it for an audiophile model.
Set up and test conditions
We used the Icon DAC with a PC and a Macbook and in both cases the installation required no extra driver. The NuForce Icon DAC is completely plug and play. Nevertheless, NuForce released an ASIO driver for Windows which allows you to bypass the Windows mixer and thus avoid any possible modification of the audio stream (amplitude, sampling, etc.). We used Foobar2000 and the Nuforce ASIO module for our listening session, with numerous CD and studio quality FLAC files. We also listened to a few SACD ISO images (DSD format) but didn’t hear any difference with the FLAC HD versions of the same recordings.
We used an entry-level set of headphones, whose reputation is firmly established – the Sennheiser PX-100 (first generation) which we normally use.
We meticulously configured Foobar2000 in order to deliver a bitperfect signal to the Icon DAC. In other words, we used the NuForce ASIO driver and set the volume to the max (0 dB reduction). The thing is however, we used a pair of low impedance / high sensitivity headphones, the Sennheiser PX-100, and the sound level was extremely high as soon as we started to turn the Icon DAC Tocos potentiometer. We also encountered a few balance issues caused by the very high attenuation (which is normal).
Based on the principle that one should ?leave well enough alone?, we reduced the sound level in Foobar2000 in order to adjust the Icon DAC volume knob. The sound stage then opened in a spectacular way.
Compatible audio resolutions
With Foobar2000, we used audio files in the following resolutions: 16 bits / 44.1 kHz, 16 bits / 48 kHz, 24 bits / 44.1 kHz, 24 bits / 88.2 kHz and 24 bits / 96 kHz. Audio streams with a superior resolution cannot be read and must be down-sampled. This occurs automatically with most audio players (Media Player, VLC, etc.).
The NuForce Icon DAC delivers a warm and wide sound, well articulated in the lower-medium and higher-low frequencies. The external power supply brings the necessary energy to offer great performances in the low-frequencies. The listening experience is always full of substance and even very bright recordings sound well balanced. The mediums are detailed and benefit from a gratifying lateralisation. The treble reaches high frequencies and we are surprised to hear such a sound from the usually short-winded Sennheiser PX-100.
The Icon DAC displays an impressive ability to bring forth many details from seemingly average recordings, thus providing them with a balance less efficient DACs fail to deliver.
Private Investigations, Dire Straits (FLAC 24 bits / 88,2 kHz)
Stupendous… It has been much too long since we’ve heard it sound so good. Love Over Gold is one of the few rock albums to have been mixed at a low level in order to respect the dynamic range ? just like Brother in Arms. We loved the guitar sound, the sound of broken glass, the sound of the strings, the lashing piano and the aerial drum sound. An absolute delight only a really good headphone amplifier / DAC can deliver.
Hurdy Gurdy Man, Donovan (FLAC 16 bits / 44,1 kHz)
A saturated mix difficult to convey without a certain amount of aggressiveness. The Icon DAC does a pretty good job with it. Donovan’s voice, flirting with distortion at the beginning of the second verse, demonstrates this DAC’s capacity to convey recording variations with unquestionable skills.
All Night Long, Lionel Richie (FLAC, 24 bits / 88,2 kHz)
Heard countless times, maybe too many times, Lionel Richie’s hit actually has a lot to offer. The Icon DAC leaves room for the male vocals to be properly heard without putting too much emphasis on female vocals. Hearing a song that had become dull to you sound like it did the first time you heard it is often the sign of good electronics.
Moonlight on Spring River, Zhao Cong / The Dali CD Volume 3 (FLAC 16 bits / 44,1 kHz)
Zhao Cong’s pipa tickles the ear while low frequencies take you to the depth of the sound spectrum (the level at 30 Hz is unbelievable!). Percussions are powerful and under control, the chorus might be a little too shy, though. One thing is certain, it will take you on a journey.
Big Jet Plane, Angus & Julia Stone (FLAC 16 bits / 44,1 kHz)
Angus Stone’s voice was equalized with a problematic sharpness during the mixing process. The Icon DAC solves this problem with no difficulty whatsoever, and showcases the artists’ vocals. Julia Stone’s voice, coming from the right as a support during the chorus is also well defined.
Avicii, You Make Me (FLAC 16 bits / 44,1 kHz)
Everything is under control at all times, but nothing moves us. Something is missing, probably an issue with the mixing. Maybe this club anthem is only meant to be played through ten speakers or more and just as many subwoofers.
Sexy Bitch, David Guetta ft. Akon (FLAC 16 bits / 44,1 kHz)
There is something strange with this hit by David Guetta, almost harmless in the hands of the Icon DAC. Everything is under control, balanced, just like Avicii’s music. While we expect to hear a thundering electronic drum kit, the falsely saturated impacts are skillfully delivered. We re-discover this exhilarating track in a very clean way.
Total Control, The Motels (FLAC 16 bits / 44,1 kHz)
This misty, atmospheric masterpiece was released in 1979. Martha Davis’s voice is delightfully highlighted and sends chills to your spine. What incredible realism! The bass, drums and saxophones are all truly convincing.
Maybe I’m Right, Linda Ronstadt (FLAC 16 bits / 44,1 kHz)
A reference to test the capacity of your audio material to deal with two layered voice tracks. Mission accomplished. The NuForce Icon DAC delivers everything the way it should be: the acoustic guitar dances with Linda Rondsadt in a truly fantastic way. The male vocals are properly conveyed, the electric guitar sounds great and has room to breath as the bass rumbles to our delight.
What about the analog output?
We will tell you all about it… in the second part of this test as we will be using the NuForce Icon DAC along with a few different amplifiers (Yamaha A-S2000, Denon AVR-X3000 and Yamaha RX-V775) as well as the new Magnat Quantum Edelstein, Q Acoustic 2050i and Klipsch RB-51 speakers.
As far as the headphones listening experience is concerned, we are sold on the NuForce Icon DAC. It is powerful and clearly stands-out from self-powered DACs on this level. If you have high impedance headphones, this Icon DAC is a great choice to use with a PC or an analog stereo source.