[size=10pt]I had posted my review elsewhere, but I'll move it here since this is the place for NFB-11 traffic. [/size]
[size=10pt]I'll start by a first impressions review of the [/size][size=10pt]NFB[/size][size=10pt]-11 as a PC/[/size][size=10pt]USB[/size][size=10pt]driven headphone amp. [/size]
[size=10pt]Sources: Asus eee PC notebook with mp3, [/size][size=10pt]AAC[/size][size=10pt]and WAV files. I've not been able to get ASIO4[/size][size=10pt]ALL[/size][size=10pt]to work with FOOBAR (this time, it did work before, hmmm), so the audio processing is still XP. [/size][size=10pt]Cans: Beyerdynamic DT990-600 ohm, Monster Turbine IEMs. [/size][size=10pt]Comparison Amps: uDac, FUBAR IV Plus, Compass, and a powerful HP out from my old british integrated.[/size]
[size=10pt]Yes, the [/size][size=10pt]NFB[/size][size=10pt]-11 can drive the 600 Ohm Beyers. You do need to use the high gain switch though, as low gain doesn’t do it. I'll max out my ears at about 40-60%% of the volume dial with high gain. [/size]
[size=10pt]Here’s the best thing I can say about the [/size][size=10pt]NFB[/size][size=10pt]-11, it is the first time I can honestly say that I can hear the difference on headphones between a 256 or 320 kbps MP3 file and a WAV file. It’s subtle, but definite. No audible difference between Apple Lossless and WAV files though. Don’t get me wrong, the mp3 files sound very good. However, switching to a lossless format is an audible improvement. [/size][size=10pt]I do have some hi-rez FLACs from HDTracks as well, and I must say those sound stunning. Great detail even at low volume, and nothing in the background at all.[/size]
[size=10pt]IEM testing: The Turbines run on the low gain setting at around 30% of the volume dial. I won’t compare the sound to the DT990s, it’s not a fair fight. I know background hiss is a problem with amped IEMs, and I will say when you pause the music, there is a very faint hiss. Compared to my other amps, the background hiss is much less.[/size]
[size=10pt]With the DT990s at full volume (no music), there is no background noise at all.[/size]
[size=10pt]As far as a [/size][size=10pt]USB-[/size][size=10pt]DAC comparison, the [/size][size=10pt]NFB[/size][size=10pt]-11 has better detail than the FUBAR or COMPASS. I do think the FUBAR goes a hair lower in the bass region..it may have a bit more power I think. However, the [/size][size=10pt]NFB[/size][size=10pt]-11 sounds cleaner all around. I do get the warning about the [/size][size=10pt]NFB[/size][size=10pt]-11 being unforgiving though, there are a couple of times listening to songs where the singer would hit a note that would pierce my ears. That was pretty rare though.[/size]
[size=10pt]In summary, the [/size][size=10pt]NFB[/size][size=10pt]-12 (since the 11 is no longer an option) should serve as the reference budget [/size][size=10pt]USB Headphone Amp[/size][size=10pt]. I can see no reason to spend more, unless you are willing to spend MUCH more. To answer a recent question, should a Compass owner get the NFB-11/12? I probably wouldn't, Compass' sound is 95% as good, and you can tweak it to higher levels.[/size]
[size=10pt]And now I can add Part 2, the DAC review. Comparing it against the FUBAR IV (Cirrus 4396?), Oppo DV-980 (Cirrus 4398?), but mostly my Sony BDP-570 (Costco version BK-57) as it is better than the prior two. [/size]
[size=10pt]I spent about two hours testing. For the first hour, I did not prefer the NFB-11 to the Sony....too close to call. After an hour, I changed my mind. The Sony beat out the Oppo and FUBAR IV with a much better bass response. The NFB-11 matches that better bass response, but adds a tighter mid-range. Vocals are a bit more apparent with the NFB-11, the Sony's vocals fall a bit further back into the sound. This was most apparent on SACD playback. Soundstage was pretty similar with the NFB and the Sony. As far as testing using PC as a source, pretty similar results to what I heard on the headphones.....mp3 files do not quite stack up to lossless, WAV files, or direct from CD....but the mp3 files still sound very good and will suffice for all but critical listening. [/size]
[size=10pt]I wish I had an old DVD player to test, as I suspect the NFB-11 would be quite an improvement....but in this case the Sony BD player really stacks up well. For me, the NFB-11 improves it only by a small margin as a DAC, so the NFB will stay at work as a PC-USB-head amp.[/size]
