Soundstage, separation and imaging
The mark of 64 Audio’s designs is the combination of a refined, mature tonality with outstanding technical ability. Nowhere is this more apparent than in the four hybrids’ ability to cast a generous stage, across which instruments are spread and then precisely played back so you can almost see them in the virtual space. The degree to which each IEM achieves this effect varies, influenced in part by tonality, but more so by the very specific design and placement of the drivers – particularly in the three tubeless Tia System IEMs.
For a relatively warm and sometimes dark-leaning IEM, Nio (M15) casts a fairly wide stage, with good instrument separation and generally credible imaging. On bassy tracks the space between instruments can get a touch wooly, but retains a sense of balance, and instruments generally don’t overlap unless they’re recorded that way. mX opens up Nio’s soundstage, with similar width but more perceptible depth. Instruments also have more air between them, which is cleaner too, and their position is easier to pin down. Panning effects are also more obvious.
Trió casts a wider stage than Nio (in either configuration), and has a better sense of layering, separation and imaging. Some have called Trió’s stage holographic, but with the exception of a few tracks that have been recorded in a way, I hear Trió as wider rather than deeper, and there’s not too much by way of stage height either. This is purely by comparison, because Trió is indeed very spacious, with superb separation and imaging capabilities.
If there’s an IEM that creates a larger soundstage than Fourté, I’m yet to hear it. Not only can Fourté – with the right material – stretch the physical boundaries of the stage well beyond the width of my head, it also spreads it outwards, upwards and downward to create what can genuinely be described as holographic space. At the same time, Fourté separates every instrument, vocal and sound effect with such precision, that you’ll be hearing layers upon layers of audio cues in familiar tracks you never knew existed. Add to that a sense of pinpoint instrument placement in the 3D space – imaging that doesn’t only place but also tracks the movement of sound across the stage – and you have the very best stage, separation and imaging reproduction I’ve heard in any headphone format, including my previous benchmark, the HD800.
Noir trades the endless expanse and precision of Fourté’s stage, separation and imaging for a warmer, more intimate, more cohesive presentation. That’s not to say any of these are short of excellent. Noir’s stage is smaller, yes, but not by much – probably closer to Trió than Fourté – and more oval shaped instead of infinity cubed. Where Fourté paints pitch black darkness between instruments, Noir heats the air up a little, giving it some padding in the same way Nio does with its warmer tilt, but in return this makes the space more natural and organic than Fourté’s surgical theatre. Imaging doesn’t suffer quite as much as Nio though, with instruments placed precisely in the space, and panning effects are just as sublime as they are on Fourté.
Lily Kershaw’s Always And Forever, from her outstanding 2019 album Arcadia, mixes electronic beats with layered effects and oversampled vocals to create a wide, deep soundscape, anchored by Lily’s pristine voice. At 2:50 there’s vocals split to the left, joined by another at 2:56 to the right, then all three harmonise together, the left and right repeating the lyrics ‘I feel holy’ while Lily continues singing. Nio faithfully recreates the stage (with both mX and M15) modules, giving each element room to breathe, and clearly maintains the three vocal layers in their own space. Trió pushes the left and right channel vocals slightly further apart, creating a wider stage with more space between the various elements of the track. Fourté doesn’t push the vocals further apart, but instead sets them slightly back in the stage, creating a better sense of depth. Noir maintains the Fourté’s sense of depth, but on a slightly smaller stage, pushing the vocals closer to centre but still distinctly separate.
Al Di Meola’s Traces Of A Tear from the 1985 LP Cielo E Terra presents a vast open space with sparse, intricate and interesting instrumental cues, often appearing unexpectedly in different parts of the stage, and occasionally panning right-to-left and left-to-right across the stage. Nio’s M15 stage is fairly wide here, the instruments comfortably occupying their own space. At 0:50 a shaker rattles from the far right and quickly pans across the stage to the left, then back again. The panning is very accurate with both mX and M15, but the location of the various instruments, while clear, is slightly less accurate than it is with the other three IEMs. Trió’s stage is again wider, and also deeper than Nio, the instruments precisely placed, and the panning effects are equally precise. Fourté’s stage is wider still, the layering of sounds more intricate and nuanced. The shaker seems to come at you from 3D space, moving closer to your eyes from the right and away from your face as it pans left. If ever you need a track to demonstrate Fourté’s holographic stage, use this one. With only the guitar strings adding warmth to the sound, Noir’s stage is vast, wide and deep here, the panning effects as realistically three-dimensional as they are with Fourté. There’s a touch more overlap between the instrument echoes, melding them together into a more cohesive whole.
Pink Floyd’s Time, from their iconic 1973 album Dark Side of the Moon starts off with a famous clock intro that…well, you know, and if you don’t, go listen. It’s an overused showcase track for imaging, separation, clarity and detail, but since it’s also one of my all-time favourite songs, I’m happy to include it here. Nio (M15) does a decent job of placing each clock in its own space, but doesn’t have the depth of space to layer them so that they don’t overlap too much, blurring some of the edges. With mX, Nio does a marginally better job, but some of the fundamental ‘gears’ of the clocks (that I know are there) are missing. Trió’s stage is notably wider here, deeper and more detailed too, with the clocks spread out on more of a 3D-axis than in overlapping rows like Nio. Almost all the fundamentals are audible, but be careful that Trió’s zing doesn’t take an eye out with some of the clock chimes in the right channel. I was almost afraid to try Fourté with a room full of brightly-chiming clocks, but as it turns out, its left me with only partial hearing loss in my right ear. Seriously though, Fourté lets you hear every chime, ding, scrape and gear rattle in real-time, creating a marvelous kaleidoscope of excited clocks you can almost touch. Noir’s warmer sound takes some of the metallic energy out of the clock strikes compared to Fourté, which is a good thing really because the smaller stage brings the clocks a little inward, closer to your head. You can still hear them all just as well as you can with Fourté.
Meiko’s (Sittin’ On) the Dock Of The Bay, off her 2018 covers album Playing Favorites, is a binaural recording by David Chesky that places instruments around a fairly large room, with Meiko closest to a ‘dummy head’ microphone in the middle. An IEM with good imaging should give you a sense of where each instrument is in the space, and also track Meiko as she moves around the microphone. It’s only Meiko and her guitar until 1:25, when a drum and tambourine start up in the left channel, and what sounds like a bass instrument of sorts in the right. Nio (M15) does a credible job, to a point. Though the drum and tambourine seem fairly close to the singer, the exact placement of the bass isn’t entirely clear. mX adds some air between the instruments, but not much, helping to focus the imaging slightly. Trió steps up both imaging and separation considerably. The tambourine, which sounded like it was being played by the drummer, is actually set off to the left of the drums, which are in turn set further back in the room, and the bass on the right is closer to Meiko, Trió’s powerful low end casting echoes off the walls that better define the dimensions of the space. Fourté adds height and even greater depth to the stage, placing the drums further back, the tambourine forward and further left, and pinpoints the location of the upright bass instrument on the right. It’s Noir, however, with its thicker and more resonant bass combined with excellent imaging, that creates both a sense of space and size, Meiko’s warmer and more intimate vocals making Noir the ideal pairing for this track.