KingRex asked me to review their new top-end headphone amp, the “Headquarter” HQ-1. This amp sells for about $850, which isn’t crazy expensive, but isn’t exactly cheap either, and does put it in direct competition with some very fine amps, both tube and solid state. According to KingRex, the HeadQuarters is designed to compete with the big boys: the HQ-1 is a Class-A MOSFET design using discrete devices, consisting of theToshiba A970/C2240 for first stage of amplification and the Hitachi MOSFET 2SK214 in the output stage. Other very nice “audiophile approved” parts are used, including WIMA caps and VISHAY resistors and an ALPS pot. The HQ-1 has one input and two outputs which are selectable by a front panel push button- one is a line-output for preamp use, and the other is the headphone output. A gold-plated NEUTRIK ¼”/6.35mm headphone jack and gold-plated, chassis-mounted RCA jacks are used. The power supply is in a separate unit that is matched aesthetically and uses an IEC power cord. The build quality is very good, and it looks very nice: I broke the HQ-1 in for 300 hours continuously before beginning the review, on top of the 72 hour burn in that the factory does. This proved very important, as the sound during the first 150 plus hours was not very promising at all. It improved significantly after about 200 hours or so. I listened to the HQ1 with My trio of 600 ohm Beyers (which is had no problem powering), and my JVC DX1000. Sources were my iMod/VCap dock, and my Denon CDRW 1500 > Music Hall DAC 25.2. I also listened to the HQ-1 with my Vinyl rig. Sound Life is funny. Immediately prior to reviewing the HQ-1, I reviewed the Audio-GD Phoenix. The Phoenix costs $1,200. The HQ-1 is $850 - about 2/3 the price, so considerably cheaper, yes, but still close in price. Yet the Phoenix is 3 times the size, probably 5 times the weight (or more), and has considerably more features (balanced operation, remote control, multiple inputs). And perhaps even more strikingly, they don’t sound much alike at all. In fact, it’s hard to imagine them sounding much different, given that they are both solid-state headphone amps selling for +/- $200 of the $1K mark. Maybe this was bad luck for KingRex – the Phoenix sets a new bar of performance in @$1K solid state headphone amps, and this is a very high bar indeed. And ultimately, it makes it difficult to judge other amps independently of this point of reference. As such, I did compare the HQ-1 to some other amps, as well, both less expensive SS amps and some tube amps in the same basic price range as the HQ-1. The HQ-1 features a lively, slightly forward sound, with a subtle but nonetheless noticeable lower treble “bite” and a slight upper bass/lower midrange “congestion”. Interestingly, the KingRex sent me a FR graph for the HQ-1, and it measures essentially ruler flat (as one would expect any well-designed amp to when the load tested is well above the amp’s output impedance, which was the case here. Here is the graph they sent: As seen above, the design was ambitious, with lots of audiophile-approved parts. But there is no doubt that the HQ-1 is has a slightly aggressive sound, and just isn’t quite as transparent as I would expect an amp in this price class to be. As one would expect, this was more of an issue for some headphones than others. With my Beyer headphones, it meant that the treble was just too biting – the DT880 especially laid bare the bite of the treble, which is definitely more forward than is natural. With the JVC DX1000, the overall sound was quite good, but here the “cloudiness” or congestion of the upper/bass and lower mids was a bit detrimental, lending things a slightly woolly sound that is totally absent on the Audio-GD Phoenix, or any of my tube amps. I also felt the mids lacked a little of the remarkable purity that the DX1000’s usually exhibit on other high-end amps. Moreover, the effect was that of somewhat homogenizing music. The differences between recordings weren’t as pronounced as I experience on my other high-end headphone amps. Aside from the slight treble forwardness, the treble was generally good. It was fairly clean, with good detail retrieval, although it was not a sweet sounding as the Phoenix, or my Decware CSP-2. Extension and air were both very good. The bass was well defined, and punchy – but as mentioned a problematic in the upper bass. The FR graph shows a *very* slight deep bass roll-off, which seems insignificant, but I did notice this occasionally, to a greater extent than the FR graph would indicate. During many songs, this wasn’t very noticeable, but there were some tracks where it was. But the wooliness in the upper bass was more notable than the very slightly lightweight deep bass. The midrange is generally pretty good. It wasn’t on par with the Audio-GD Phoenix in terms of richness or transparency – it’s a little on the drier side. I also felt, compared to the other SS amps I have heard in its price class, that it lacked a little bit of transparency and resolution. Songs like Stereolab’s “Eye of the Volcano” were very crisp sounding, as they should be. “Ring Them Bells” from Heart’s “Desire Walks On” was reproduced with a very engaging reproduction of the vocals. However, on “Straight, No Chaser” by Kristin Korb, which is a terrific recording sonically, things were a tiny bit muffled and “wooly” versus how they sound via my other top-end amps. There was also a little bit of grain present that I do not find in my other high end amps. The soundstaging capabilities of the HQ-1 are excellent. Depth is very good, as are soundstage width and definition. The spatial presentation was quite convincing. The one headphone I owned that the HQ-1 sounded especially good with was the Shure 840. Here, I thought the extra bass bloom and slight extra treble presence seemed to work really well. In fact, it was the best sound I had heard from the 840. This was a very enjoyable pairing, in spite of the fact that it’s unlikely anyone will pair a $900 amp with $200 headphones. It was a case of the HQ-1’s colorations synergizing well with the 840’s. There are undoubtedly other headphones that would sound very good with the HQ-1, but it wasn’t a great fit with the majority of mine, because it does have a distinct flavor, which isn’t very consonant with Beyer headphones. I don’t want to make too much of a big deal about all this, as it will be overblown – the HQ-1 isn’t overwhelmingly colored, or anything like that. We are talking about fairly subtle things, here. However, in an amp at this price level, even the very subtle shadings need to be noted. And the HQ-1 is best characterized by a slightly dry midrange, and slightly present lower treble, and a slightly wooly upper-bass, which is overlaid on all recordings. So the prospective buyer will have to be aware of these things. The sound does have some colorations, and they are of the generally more problematic “additive” rather than the less problematic “subtractive” sort. Because of this, my stable of headphones don’t really sing with the HQ-1, in the main, the way I expect them to when listening to them though what is designed to be a “Statement” amp. Conclusions So the “HeadQuarters” is a bit of a tough one for me. The KingRex people are VERY nice, and I liked their DAC, which I reviewed previously, a lot. So I really, really WANTED to like the HeadQuarters. Unfortunately, I really don’t think it hits the mark. The HQ-1 is a pretty good sounding amp, and is built very well, and is pretty to look at. But I had a hard time finding much that was special with the HQ-1 sonically, and in this price range, the overall performance level should be higher, IMO. With the Shure 840, the HQ-1 was really enjoyable to listen to, and made the Shure sound as good as I have heard. But with most of my other headphones, the HQ-1 was an underachiever. The HeadQuarters has a distinct personality that isn’t going to work universally, and the overall level of performance is simply not on par with other amps in this price range, and even some that are well below the price of the HQ-1. I have sent this amp to MrArroyo for him to audition and review. He has different headphones than I do, as well as different ears, and will be able to provide some very useful additional perspective. As for me, for the $850 selling price, I can’t really recommend the HQ-1 with much enthusiasm, and certainly think that more than the usual care in matching with the right headphones would be advisable for someone considering buying one.