This mini-review can be considered as a sort of add-on to my previous review of the Audeze LCD-2 among other headphones, linked here: http://www.head-fi.org/forum/thread/548875/review-audeze-lcd-2-hifiman-he-6-stax-sr-507-stax-oii-mki-bhse-et-al. This mini-review also references the Notes files from that review, specifically the OII/BHSE vs LCD-2/GS-X section. Reading of that section may be beneficial to assist with understanding some parts of this mini-review.
Posting in a new separate thread to make this thread easier to find, this is just a comparison of the HeadAmp-built KGSS (recently discontinued, earlier this year) vs the Blue Hawaii SE (BHSE), done for my own personal benefit to decide which amp to keep, as I don't intend on keeping both amps long-term.
Standard disclaimer applies here as well: though I've owned the BHSE for just over 2 years now and have listened to it very frequently over that time, the KGSS has been in my possession for just about a couple of weeks as I write this. Hence, the impressions below are not necessarily final and may change for me at a later point in time. I won't be writing anything further about the amps though from this point forward.
And here's a pic showing the amps stacked (with power disconnected, of course): http://www.head-fi.org/image/id/1655248/width/1000/height/800
Same as posted in the above-linked review, except the analog interconnects changed to Blue Jeans Belden 1800F XLR type, to use both of the amps solely in balanced mode. I prefer balanced mode on my BHSE to help counteract its low gain (just my specific amp, as when I ordered it I requested a Normal-bias Stax jack).
Tubes on BHSE were the stock Mullard EL34s.
All listening was done with just the Stax OII MKI.
Alison Krauss & Union Station - Paper Airplane - "Paper Airplane", "Dimming of the Day"
Massive Attack - Mezzanine - "Angel", "Teardrop", "Inertia Creeps"
Megadeth - Countdown To Extinction [MFSL] - "Sweating Bullets"
Symphony X - Paradise Lost - "The Walls of Babylon"
Carlos Kleiber & VPO - Beethoven Symphonies 5 & 7 - "Symphony No.5 in C minor - III. Allegro" & "IV. Allegro"
Julia Fischer - Bach Concertos - "Violin Concerto No.1 in A minor - II. Andante", "Violin Concerto No.2 in E - II. Adagio"
There was really only one question for me personally between the KGSS and BHSE: which amp did I want to keep after hearing and comparing them?
I still haven't decided, mostly in part because the decision was made trickier after hearing the amps. But before I continue with the sound comparison, I should add my motivations for either amp:
+ solid-state (I'm averse to tubes in general, the BHSE is an exception of course)
+ single-chassis design (also averse to dual-chassis setups)
+ less AC power consumption & hence a bit cooler than BHSE at full temperature (because who wouldn't want to save on their energy bill, right?)
+ more conducive to stacking with my HeadAmp GS-X (for a simultaneous electrostatic/dynamic setup)
+ less expensive
+ Amazing sound quality (as in, 11/10 good)
+ Um yeah, that's pretty much it - the KGSS defeats it on just about every other point
So when the KGSS is more up my alley from points of view excluding sound performance and the BHSE can defeat it on sonic merit alone, that leads to the obvious question: "How exactly does the BHSE sound better?"
I want to state first that the BHSE has ruined me forever. Forever I tell you, because it's the single most amazing thing I've ever heard, anywhere. Words simply do not do this amp justice. It really just needs to be heard and experienced for yourself, and then maybe one could understand where I'm trying to come from. It offers an otherworldly, 11/10, totally surreal listening experience that transcends space and time. And no, I don't think I'm overpraising the amp either - it really is that good.
How close is the KGSS? Pretty close I'd say for most intents & purposes - it's essentially the same sound, or type of sound, if you will. Anyone who's heard the KGSS should have a really good idea of what to expect from the BHSE - it doesn't radically differ from the KGSS in any major aspects. And the KGSS is a very good amp on its own - the fact that I was bowled over by it after 2 years with the BHSE should speak to its quality. I didn't even notice a single difference at first when I first set up the KGSS and used it for background (non-critical) listening.
But it's when I started critical listening that I started picking up on the slightly less-than-stellar aspects of the KGSS, and the more I noticed them, the harder they became to overlook. The KGSS' weak points include:
- Semi-flabby, semi-undefined bass
- Lack of truly deep-sounding bass & mid-bass for that really low, really full ooze-like factor
- Congestion of multiple densely-packed layers
- Relative inability to produce very loud volumes without some type of negative side-effect (distortion, congestion, or just simply not being that loud)
- Similar to above, relative failure to get instantly loud or instantly quiet (as in, time reaction)
- Limited dynamic range - not as loud or as quiet as BHSE
- Relative inability to produce low volume and maintain clarity at the same time
- Limited soundstage depth & width - too closed-in, forward, and stuffy. Orchestra on classical CDs not spread out enough and instruments in back not far away enough.
- Loss in scale as a result of the limited soundstage depth/width (orchestra not as big-sounding)
- Loss of some clarity
Overall, to me the KGSS made the OII sound more like a step towards the Audeze LCD-2, and by that I don't mean anything good. Refer to my LCD-2 review (linked at the top) to see the points where I criticized the LCD-2 vs the OII.
My #1 favorite track on the OII/BHSE, Julia Fischer's "Violin Concerto No.2 in E - II. Adagio" from Bach Concertos, just wasn't the same on the KGSS. It was still very well done, but just not the same - the KGSS lost part of the violin's intensity and all of the track's slight radiating-heat quality. There was also some loss in detail that negatively affected the violin - volume modulation, bow speed modulation, bow pressure, E-string tinting, etc.
To put it the other way, the BHSE can be seen as having these advantages over the KGSS:
+ Very clear, very defined, and truly deep-sounding bass & mid-bass
+ No congestion of layers regardless of music complexity
+ Ability to produce very loud or really quiet volumes, instantly if necessary
+ An extra layer of "dimension" to the soundstage for a truer 3D experience - everything from far left to wide out to far right (or near left/right, as the case might be). Literal air sweeping across the soundstage as well for that expansive feeling to accurately reproduce concert hall acoustics, if on the recording.
+ Ability to produce convincing scale (small vs big instrument sounds leaping out of the soundtrack, w/ large sections sounding like a huge mass or alternately single instruments/voices sounding small)
+ More clarity
+ Ability to reproduce volume intensity* (at either loud or quiet levels)
+ Ability to reproduce a sense of supreme directness to a voice or acoustic instrument
+ Ability to reproduce a "radiating heat" quality from the combined presence of musician & instrument, as if every instrument itself is like a heat source on an infrared image, if the sonic image could be paralleled to a visual image
Going back to the Julia Fischer track, it exemplifies extremely well so many of these qualities and I highly recommend it for any owner of the Stax OII MKI regardless of amp, even if not the BHSE or KGSS. The best way I can describe the BHSE experience is that it puts that track on a higher plane of existence - higher than anything & everything else I've heard (see my profile for equipment I've heard/owned). Fischer's violin is hair-raisingly intense and the orchestra around her so alive on the OII/BHSE - no other headphones I've heard get remotely close.
* IMO, louder volumes can't deliver much impact if they're not also intense! And the OII/BHSE can produce intensely loud - whether it's Eva Cassidy rising in volume on a sad song or an orchestra unleashing Beethoven's fury, for example.
If anyone is thinking "Well I simply must have the BHSE now if it's that awesome!" at this point, I'd have to call for a change in thinking.
Keep in mind that my BHSE experience is limited to my ears alone, on my system, and I can't speak for anyone else who'll inevitably be using a different system. IMO, the performance of something like the BHSE is highly dependent on the source component and I happen to love my source, the Plinius CD-101, as well. It's really the total system, not just the OII/BHSE, that gets the 11/10 rating from me.
So my recommendation for anyone thinking about the BHSE is to factor in a really good source to go with it, if you haven't already done so. And by really good source, I really don't mean anything cheap - good sources tend to cost serious money, and really good sources tend to cost even more. Not that something expensive is necessarily good though - but typically good stuff is expensive, that's just how it goes.
The KGSS would make for a better investment on less than high-end sources and if that describes yours, that'd be my recommendation instead. Not that the KGSS is bad, it's a great amp - amazing, even. On my 10 scale, I'd rate it maybe 9.5/10. But if the KGSS is amazing, then I'd call the BHSE even more amazing. Amazing-er. Amazing + 1. 11/10! So good it'll make you laugh and cry! And I mean that literally!
Let me put it this way: sonic perception is not only subjective, it's also extremely hard to describe with the written word, or words at all. And when I listen to the OII/BHSE, there are simply no words that can describe it. You need to listen, and when you listen, and close your eyes, the real world disappears and the music takes over, and then the only thing you're left with is an emotional, soul-stirring experience that just doesn't leave you when you're done listening. No, it changes you on the inside forever. It's something like that.
Mod note: This thread was locked by request.