But, you know what you
can't hear at Indulgence?
The Zeus-XR // 2-wire 1960s // AK70-Kai Super-Combo!!
I decided to take it slow, and try the AK70-Kai first, wanting to explore the differences between it and my daily driver, the Onkyo DP-X1. Please do keep in mind that the following impressions were taken with an Empire Ears Zeus-XR and an Effect Audio Lionheart, with a merely basic recollection of the stock AK70's sound.
And, before I go into the sound of the AK70-Kai, I must explain that this mod was done by Ryuzoh of Musashi Sound Tech, Japan. It's a pretty extensive revamp of the AK70's internal components, including op-amp swaps, clock changes, cap replacement, etc. Apart from affecting the sound of the product, it does add a tiny bit of hiss; it now hisses a hair less than my DP-X1, which is still great and absolutely negligible once
any semblance of music starts playing. It also requires you to wait, after music stops playing, 3-5 seconds before you unplug the cable from your player. Once this time passes, the amp circuit will shut off and you can safely unplug your IEM; if you unplug your IEM suddenly, you'll hear a pretty loud pop on the left side, which I reckon isn't too healthy for all parties involved. I'm not sure if you can discuss any specialised alterations to the mod with Ryuzoh to prevent this from occurring, but it is the case for the standard mod. Now, with that out of the way, into the sound impressions!
As usual, we start from the bottom. The AK70-Kai's bass is simply awesome, and there's really no other way I can put it. It trumps the DP-X1's bottom end in terms of impact, resolution, layering, and most of all, isolation. The DP-X1's bass has a tendency to blend with the lower-midrange, mostly because they share similar tonalities, positions in the soundscape, and dynamics. The AK70-Kai avoids this altogether; the bass hits harder, has a more natural tone, and has brilliant texture to counterbalance its richness and roundedness. What sets it apart, literally, is its depth; the AK70-Kai's bottom-end is placed deeper in the soundscape. This does two things: Firstly, it separates it from the rest of the frequency range without losing linearity. Secondly, placing it deeper into the mix compensates for how warm and impactful it is, such that when it does hit, it aligns perfectly to the lower-midrange. Air is one thing the mod thankfully doesn't sacrifice in doing this, and extension has also been given a healthy boost, adding incredibly satisfying rumble and physicality to baritone instruments and bass notes.
The AK70-Kai's lower-midrange is the first place where I'd knock off some points against it; it isn't as bodied, natural and smooth as it was stock, and also less so than the DP-X1. However, where it gains back those points is in texture and resolution. Listening to cellos and bass trombones are simply entirely different experiences, with jaw-dropping texture, rumble, and dynamics; you can literally
feel the bow pull against the string and the body of the instruments vibrating into the microphone. The middle midrange retains its intimacy from the stock AK70, sounding overall more focused, energised, and engaging than the laid-back and nonchalant DP-X1. An interesting quirk that's resulted from this is the more intimate presentation of the AK70-Kai can be mistaken for it having a smaller soundstage than the DP-X1, especially in terms of vocals. However, only after listening to enough material, can you truly tell that the AK70-Kai's soundstage actually expands further, wider, and taller than that of the DP-X1. But, the recording has to take advantage of that added space.
Finally, treble-wise, the AK70-Kai and the DP-X1 have entirely different presentations. The AK70-Kai has a brighter treble that's better at keeping you on your toes, providing clarity to counteract its rich musicality, but is less forgiving to peaks in either the recording or the IEM. The upper-midrange of the AK70-Kai has been given some sparkle and air, and it's done both good and bad. Thankfully, the AK70-Kai's tonal balance has been kept intact, but it is more prone to sibilance than the stock AK70, and isn't necessarily as liquid-sounding and buttery-rich. However, what this compromise has been made for, is fantastic L/R/C separation, impressive imaging, and clarity. The AK70-Kai has left-right-and-centre separation that is only second to devices such as the SP1000, WM1Z, and Hugo 2. It's the one thing I realised the DP-X1 never even had; the ability to hear every instrument as they were laid out in the mix, and even hear entire trips when instruments cross the centre-image as they go from left to right, and right to left in Michael Jackson's most fancily-mixed records. It's a unique experience I've only had to the pleasure of hearing in
much pricier gear, and its a compromise I'm willing to make for a "hotter" treble.
And then... I put a 2-wire 1960s into the mix...
The 1960s immediately gives the entire presentation a blacker background, improving dynamics, decay and micro-detail retrieval. Surprisingly, it isn't as dark and ultra-rich as I remembered the MS demo to be; I reckon it's a matter of source-matching. Despite this, though, the upper-mid heat that the AK70-Kai was giving me is now attenuated with the 1960s, and resolution has increased by means of extension (especially up-top). The 1960s has also given the Zeus's bass a more rounded and full quality, sacrificing some air for a more natural timbre, and further built upon the AK70-Kai's beautifully textured lower midrange with a more bodied, weighty, and thick presentation, making it sound all the more visceral and physical. A welcome surprise was immense soundstage expansion, but without the recession or pushing back of vocals. The 1960s inherently has a forward and bodied midrange, and this has allowed the XR and the AK70-Kai to maintain their intimacy, engagement and power, whilst pushing everything else on the horizon further horizontally and vertically. Soundstage height is a real highlight with this cable, and it has made the Zeus's soundstage proportionally huge, with linear dimensions in width, depth, and height. It's a cable that complements everything the Zeus and AK70-Kai already do so well, and even corrects some of the issues I've found with the pairing. It's not as ambitious resolution-wise, imaging-wise, texture-wise and expansion-wise as the 4-wire version, but I definitely prefer the 2-wire version in terms of tonality... and pricing!
Now, it's definitely worth noting that I've only clocked in a mere couple of hours of listening to this combo, but it's certainly the first time I've felt like I've come close to unlocking the Zeus-XR's fullest potential. I posted a while ago on the EE thread (and maybe this thread as well) that I've been perplexed by the XR, because I think it's an absolute monster of an IEM, but it constantly feels like it has more room to grow. I can honestly and happily say that now, that room has gotten significantly smaller, and I've finally felt like I've done the XR a complete and absolute justice; going anywhere further than this would be a pure luxury. I hope you've all had a jolly good time reading these impressions and please feel free to ask any questions you'd like about the combo; I'll be more than happy to entertain you lot
Until next time (which is probably in the next couple of minutes),
mi amigos...
