I just picked one of these up based on the reviews on Amazon as well as a few reviews on here. And while I is a dual purpose integrated hybrid/tube amp and headphone amp, this amp really earns its money as the integrated amp. It does the headphone thing pretty good, but I have to be honest. I can not say that it is better than a properly configured Asus STX's headphone out, but its only marginally more expensive than the soundcard. But, I do not think I would be doing this thing justice without talking about its speaker driving abilities as an integrated amp. As an amplifier, most will rule it out due to its limited specs of 16.5 watts @ 8 ohms.Well, I have to say this things sounds better than two of my $800 Integrateds (NAD and Sony ES). If you have somewhat efficient speakers and not trying to fill a large room, this thing will drive speakers to loud but enjoyable volumes with ease. This is perfect for an office or bedroom. This thing has a tremendous soundstage and plenty of low end grunt, without sounding bloated for exaggerated, even through bookshelf speakers, Even with a flat eq setting on the STX, it sound full an balanced with the right amount of glassy sparkle
with a touch of midrange complexity.
edit: After spending an entire 2nd day with this and dedicating more time with headphones, I'm more impressed than I was yesterday. I think when I used the headphones yesterday, I had the GE tubes in, which sounded like they lacked a bit of detail compared to the stock tubes. To drive the DT880 250 ohms, I only have to use about 30 percent of the volume to get to a pretty loud output. The headphone outs are excellent.
These take 6N3 or equivalents. As for tube rolling, I feel a lot of people get caught up into it so much that they hear things based more on expectations than reality. Judging tubes is one thing that I feel I am more experienced in than a lot of people, as I've not only been using them for 30 years, I've also done a lot of tube amp repair work, as well as some building and modification for professional musicians. Although most of my experience is on the guitar amp side, I can assure you that guitarists are just as picky as audiophiles. I started out with the stock Chinese tubes, which appear to be Shuguang. I also bout about 4 sets of GE 5670W's. The thing people miss about tubes is that the tolerance for any manufacturer is all over the map. The output on one tube from the same maker can be up to 30% from the next tube of the line. If you have a tested or a reliable vendor that measures and tests tubes, I contend that a cheap tube that is strong and within spec with sound nearly as good as the expensive tube within the same specs. No guarantee just because its more expensive it will sound better. The other point I would like to make is that most designers design around evaluations done with a specific tube. So, they tweak according to what they are hearing with a specific tube. In my case I think the stock tube sounds better than the GE tubes. The GE tubes sound as if they have more gain, resulting in a little more boomy sound, but the stock tubes sound more natural to me. Both tubes have pretty small plates and seem quiet and free from microphonics.
I highly recommend this amp for a study or bedrooms. It's simple looks cool and sounds like an amp 3 times its price. I promise you that you will be surprised the sound that comes from this thing. As for the headphone amp, I think this may be overkill for just that. I rate is a very good, but not OMG good.
FLAC -> Asus STX -> Qinpu A-6000 Mk2 -> Kimber 4VS Kables -> Dali Lektor 3 speakers
Edited by scottosan - 10/2/13 at 6:51pm