Review - Drop Cavalli Tube Hybrid (CTH)

KZ ZSN (sub 50€ Battle)

I purchased this IEM a couple of months ago, by accident. At the time I was actually ordering the KZ ZSN Pro but luck would have it that I clicked on the wrong model. I was pleasantly surprised by the build quality when I received it and though it had a decent sound but I’ll get to that in a moment.

As a first review I wanted to actually post a different IEM. My intention was to post a review of the Tin T2, the IEM that had most pleased me to date and the one that I made most of my comparisons against. However, luck would have it (again) that a couple of weeks ago the right side decided to die. I did order another T2, which has arrived and I will post that review soon, but again, that’s a different topic. The truth is that I ended up focusing more on the ZSN, without comparing it, and the sound started to appeal to me more and more. I have received various sets of IEMs since then, and while some seem to be technically superior to the ZSN, I keep picking up the ZSN whenever I just want to listen to music while doing other things.

So, as luck seems to have played a part in this IEM getting more attention than the others, I think it deserves to be the first IEM review on this blog!

Anyway, on to the review!

Disclaimers and info

As is noted by the previous rambling (if you didn’t just glaze over), I purchased the KZ ZSN with my own money and this review is just a personal and honest opinion.

Unboxing and first impressions

The packaging of KZ products varies very little, so if you have seen the box of one KZ then you have an idea of what it looks like. It is nothing special, although the IEMs are well protected and the packaging works, so no complaints.

Inside the packaging there are the two IEMs, the cable and a selection of KZ silicone tips. Upon extracting the monitors, the first impression is of quality. I am not talking the quality of some high end offering, remember we are in sub 50€ territory, by they certainly look well built and the metal plate on the exterior, in a dark grey in my case, offers an impression way above its price bracket. The interior is a tinted translucent plastic that allows you to see the internals of the monitor.

The cable is a simple bronze coloured braided cable, this is included with the majority of KZ IEMs at the moment. It is quite thin and feels a little plasticky, but it does its job ok and is nowhere near as bad as some cables included by other brands.

One thing to note is that the ZSN uses the “Para C” connector which has the pins recessed in to the connector. Other KZ cables will work but they will not look correctly seated on the connector.

Build quality

The first impressions of being well built continue when holding and using the ZSNs. They are light, small and well shaped, at least for my personal fit. Even upon close inspection, they still show a build quality way above their price range.

The change to the way the connector fits, with the recessed pins, means that it feels sturdier than on other KZ offerings.


Now, in the world of IEMs, comfort changes a lot from one person to the next. Nobody has my ears and I can only speak for myself, so what I say is to be interpreted very broadly. I find that the ZSN fits inside my ear better than other larger IEMs, but that is mainly because the form of the shell fits my ear well. However, I never really forget that I have these in my ears, they are not comfortable enough to just “disappear”. I recently took them on a 4 hour flight, along with the T2 which I wore on the way back, and to be truthful, the ZSN were tiring to wear (comfort wise).

I’m afraid that I can’t really say what the comfort is like with the stock tips as I really don’t like silicone so I use foam tips on all IEMs. This will also be something to take into consideration when discussing the sound.

Power requirements

I don’t know the specs for these IEMs but based off of my use with various sources (phone, DAP, amp etc) these are pretty efficient. My weakest device is my phone and I could get to decent listening levels without maxing it (maybe around 80%), on the M0 around 40/100 on high gain with the Atom at around 30% on low gain. You must take into account that I don’t normally listen to music very loud.

General listening

I have used these IEMs a lot lately, they probably racked up 80% of my listening time over 3 weeks, whereas I have been comparing them more to others over the last 7 days or so. I have listened to all kinds of music through them and to be honest, I have found them to respond well to all genres.

At first I had the impression that they were low on bass, however, when the tracks called for it, such as when listening to hip-hop, the bass became very present. When listening to acoustic songs, mainly with female vocals, the ZSN reveals plenty of detail but without sounding harsh. Even with electronic music, the bass maybe wasn’t as present as with the DT6 but it was clear and articulate.

I also used these on various flights, powering them with the Shanling M0 or the M2x, and while these are not the most isolated IEMs, they isolated enough that I didn’t need to increase my music in order to be able to ignore the drone.

When switching between sources, the differences are noticeable on the ZSN but I do not feel that these need any specific source or amplifier as could be the case with othe IEMs.

Detailed and Comparative Listening

Originally I was mainly comparing these to the TIN T2, until it decided to fail. The comparisons I have done over the last week or so have been (mostly) with the replacement T2s and the ZS10 Pro and the Senfer DT6.

BASS: I said above that, at first, I felt that bass might be lacking, this is definitely not the case. The bass is very present, even down towards sub bass levels, however, I found that it was easy to distort it if EQ was used to try and increase it more (not that I could ever need to personally). I also find the bass to be pretty clear and articulate, although it is not as detailed and fast as the ZS10 Pro, nor is it as rumbling as the DT6. In comparison to the Tin T2, I would say that the ZSN pulls ahead in the bass department, offering more bass and slightly better response and speed.

Listening to Busta Rhymes “Gimme some more” and other tracks from the Extinction Level Event album, I really enjoyed the bass on this IEM. I also like the way the ZSN reacts with upright bass. Listening to Carol Emerald “Back it up”. it’s easy to hear the tonality and the effects used on the Bass.

MIDS: I feel that the mids on the KZ ZSN are slightly recessed, while it does react very well to bassy tracks, this can sometimes make the IEM seem lacking in mids and voices sound slightly behind. When listening to a few songs that were piano only, I found the ZSN to be very pleasant, more so than the ZS10 Pro, but as soon as other instruments were added, especially string instruments, the ZS10 Pro offers far more detail and the ZSN can sound a little “cluttered” in comparison.

However, some songs that are also busy, such as “Black Muse” by Prince, sounded great on the ZSN, with good instrument separation.

HIGHS: I haven’t found the IEM to be sibilant and harsh, except on tracks that are harsh themselves. For example, “China In Your Hand” by T’Pau sounded sibilant and thin, but other recordings that are better balanced cause less harshness than other offerings.

In this regard, I prefer the highs of this IEM to the DT6 but I prefer the T2 and the ZS10 Pro.

I do not find the soundstage very wide on the ZSN but then again I don’t find it very wide on any IEM (so far). While the imaging is not bad on these, the ZS10 Pro offers much more clarity and definition in this regard.

The clarity of the ZSN is present and lets you hear the details, however, I find detail retrieval much better on the ZS10 Pro and on the Tin T2, while the DT6 falls a little behind.

When comparing the ZSN to the others, it is as though the sound through the ZSN has been masterized in comparison to the others. It doesn’t sound veiled but it does seem like someone has put a ribbon around the outside and pulled everything together, whereas the ZS10 Pro and T2 have much more separation between things.

I also tested the ZSN using the M2X to compare single ended to balanced outputs, using the NiceHCK 8 Core balanced cable. I find that certain tracks that sound a little cluttered in SE benefit from the balanced option, this seems to separate the instruments slightly better. A couple of tracks where I noticed this to a larger degree were “Que Suerte La Mia” by Estopa and “Killing In The Name” by Rage Against the machine. Using the SE output, The Estopa track became rather muddy when the spanish guitar and bass came in, the Rage song was also a lot cleaner using balanced. This could obviously be the placebo effect, without a blind test I can’t guarantee, but I found the difference very noticeable (I made sure the volume matched).

Measurements and graphs

As always, please note that the measurements and graphs posted below are taken by me and should not be used in comparison to graphs or measurements posted by other parties. My system is far from industry standard and will not match in calibration to those made by others.

I do stay as consistent as possible when taking measurements so that they are at least relevant among themselves. For this I use the EARS sistem, being fed by a Topping D10 into a JDS Labs Atom, returning into REW. Stock cables are used unless otherwise noted and NewBee Foam Tips are used I will explain in more detail in a post at some point.

Looking at the frequency response of the ZSN, the bass does extend pretty low with very little drop off. There is a clear peak at around 2.5kHz then a pretty steep valley before another 10kHz peak. To be honest, if I had looked at this graph before listening to them, I would have guessed that the 10kHz peak would have bothered me but I haven’t found it to be the case.

Conclusions and final notes

I can certainly conclude that I do like the KZ ZSN. At the time of writing this review you can get them for less than 20€ on Amazon or for less than 15€ direct from China. These are an incredible value for that price.

The are not the most detailed IEMs but they don’t lack the details that need to be there. I have found them to be great for listening to music while performing other tasks, especially with music that needs a good bass response without being overpowering. The mids are slightly recessed but that is only really noticeable when the track has a lot of bass, whereas the highs perform well.

When performing mundane tasks, such as washing my car, I usually choose the ZSN. Whilst I usually pair them with the Shanling M0, I feel these are ideal for those of us that listen to Spotify directly from our phone.

Would I recommend these?... For less than 20€?... Yes!


(This post was originally published on the 18th of July 2019, the published date was updated when English and Spanish entries were divided on the 30th of July 2019)