In my opinion, cable doesn’t have a “sound” which you can describe by itself like IEMs in terms of lows, mids, treble. Cable is a medium that could shape up and fine-tune the sound signature or expand the soundstage perception, something you can describe relative to IEM under the test or relative to another cable you compare it to. What you hear is a synergy between 3 elements in the sound chain: the source, the cable, and IEMs. Thus, it’s easier to describe the sound when you replace one of these elements and note the change associated with it.
In this sound analysis I used 64 Audio U18t with Lotoo’s LPGT, A&K SP1000 SS, and iBasso DX200Ti w/amp8, playing a selection of the test tracks, such as Agnes Obel “The curse”, Sandro Cavazza “So much better” (Avicii remix), C-Bool “Never go away”, Ed Sheeran “Shape of you”, Galantis “Hunter”, Iggy Azalea “Black widow”, Indila “Boite en argent”, Robin Schultz “Oh child”, David Elias “Vision of her”, and Michael Jackson “Dirty Diana”.
Relative to U18t, I hear OSLO pushing soundstage nearly to the limit of holographic expansion. In theory, you can’t expect improvement of soundstage if the monitor is not capable to support it. As they say, you can’t polish a turd. But some cables can limit the soundstage, especially if it’s a “warmer” cable, or they can expand it to a level where it becomes unrealistic. Here, the perception of soundstage expansion, in both width and depth, sounds realistic, expanded, and natural.
In terms of tonality, it enhances U18t to sound more organic, more natural, more balanced without sacrificing the retrieval of details or the resolution. There is some compromise in sound transparency because lower mids get a little fuller with more body, giving the mids more warmth and smoothness, but this coloring doesn’t muddy the sound or take away from its resolution. It gives U18t a more musical tonality and the change will vary depending on what you are comparing it to. For example, it will be subtler when comparing OSLO to EA Leo II, but a lot more noticeable when comparing OSLO to a brighter EA Horus.
U18t with OSLO gives its sub-bass a deep rich velvety extension, more typical of analog performance, while mid-bass feels faster which makes it sound tighter and more controlled. As already mentioned, lower mids have more body, while upper mids are still detailed and resolving and sound more natural and smoother. No surprising peaks in treble either, upper end of U18t with OSLO is natural and still well defined.
Again, keep in mind, I’m describing the sound of U18t and how OSLO cable fine-tunes its performance. In the following sections I will go over comparison to other cables, and pair up with other IEMs.
Consistent with my cable testing philosophy, I used the same IEM (U18t), the same source (LPGT), and only changed one variable at a time to note the sound difference I hear. Please keep in mind, when I’m describing the sound, in terms of soundstage/lows/mids/high, I’m referring to the sound of U18t as I hear it.
OSLO vs EA Leo II – I hear the soundstage with Oslo to be as holographic as Octa (8wire) version of Leo, maybe even with a touch more width noticeable when listening closer to mids/vocals; definitely more staging depth in comparison to 4wire version of Leo. With bass, I hear Leo to have a little more (higher in quantity) sub-bass rumble while Oslo brings more of a faster mid-bass punch, and this difference is very noticeable. With either of the cables, I hear U18t to have similar smoother, fuller body lower mids, but upper mids are slightly different. With Leo they are a little smoother and slightly pulled back (more intimate), while with Oslo they are a little brighter and more forward, a bit out of your head. Treble also has a little more sparkle with Oslo, while a touch smoother with Leo.
OSLO vs EA Lionheart – with U18t while the soundstage depth is very similar, I can clearly hear Oslo to be wider in soundstage, giving the sound a more holographic perception. When it comes to the sound, there is a clear difference in the lower end where Oslo has a deeper and higher quantity sub-bass rumble and faster and harder hitting mid-bass, while Lionheart makes U18t bass a little slower and has less quantity in comparison to Oslo. Lower mids are also a bit more neutral with Lion, while have a touch fuller body with Oslo. The rest, upper mids and treble, I hear to be nearly identical with U18t between these cables.
OSLO vs HSA Redcore – while soundstage depth here with U18t is similar, soundstage width difference is quite noticeable with Redcore being narrower and Oslo expanding wider. With bass, again, I hear more sub-bass rumble and punchier mid-bass impact with Oslo in comparison to Redcore, Oslo definitely tightens the bass, makes it more articulate, faster, and punching harder through the mix, while Redcore bass rendition with U18t sounds a little slower and softer. Lower mids are a touch more neutral with Redcore, while Oslo has a little more body. Upper mids and treble between these two with U18t have the same tonality, but a difference in presentation. With Redcore and U18t I hear mids/vocals to be more forward in comparison to Oslo and U18t where upper mids/vocals are more balanced.
OSLO vs PS Tri-Copper – didn’t expect to hear this level of similarities in tonality when tested with U18t, but there are a few differences as well. Oslo soundstage expands wider and a little more out of your head, making U18t to sound more holographic. With bass, these two have a lot of similarities when paired up with U18t, nearly the same level of sub-bass rumble and mid-bass impact. Also, lower mids are quite similar, with a fuller body in each pair up. In upper mids, I hear U18t to be a little brighter with Oslo while Tri-Copper sounds smoother. Treble is very similar. Aside from a soundstage difference, and obvious advantage of Awesome-cable connectors, the overall tonality and balance is quite similar.
OSLO vs PS Tri-Silver – here the soundstage expansion with U18t is nearly identical, in both width and depth. Bass is very similar too, maybe with Oslo punching a little harder in mid-bass, similar to how Tri-Copper compares to Tri-Silver. With U18t, lower mids are a little more neutral relative to fuller body lower mids with Oslo. Upper mids are very similar in tonality and presentation, and treble has a touch more sparkle with Tri-Silver. When it comes to tonality and presentation while paired up with U18t, Oslo is closer to PlusSound, taking the best of Tri-Copper and Tri-Silver and adding Awesome-plug into the mix.