KZ ZS7

The ZS7 has been out for a while now, but I haven’t had a chance to take a listen to it until more recently, thanks to Head-Fier, HiFlight, sending me his review sample, which was provided to him by YooAudio.com.

The ZS7 is the newest version from their line of Campfire clones, starting with the plastic ZS5, the metal ZS6, and now this. I never had the opportunity to listen to the original ZS5, but both the ZS5 v2 and ZS6 had very wide soundstage, impactful bass, but incredibly sharp, harsh, and sibilant treble.

From listening to the ZS7 now, it looks like Knowledge Zenith (KZ) has taken some of the feedback and toned down the ZS7’s treble range and made it a much more enjoyable listen, which is nice to see. The ZS7 still features a big bass boost that can occasionally bleed over and become muddy in busy sections, and struggles a bit with busy sections of songs.




The toned-down bass does also make the soundstage narrower than the ZS6, but that’s an acceptable trade-off since the ZS6 treble was piercing bright and I could not use it for more than just a few minutes.

Anyway, this is going to be a rather short review, but I believe the ZS7 is a decent purchase, but for the same price range of $50 or under, I would strongly recommend the following IEMs:

KZ ZS10 Pro – More balanced sound, slight V-shape, warmer, good extension.

Tin Audio T2 – Neutral Diffuse Field sound. Good mids. Slightly harsh, but cleaner and more detailed than ZS7

I'm still not sure who came up with "earphone" but I digress... For me, these are a great sounding, inexpensive set of IEMs. They are warm and musical with a punch in the mids. I have trouble in the 7kHz range and these compensate marvelously. of course, YMMV, but for the price, you really cannot go wrong.

The KZ ZS7 is one of KZ’s newest additions to its ZS# series of earphones and is the third to use a polygonal Campfire Audio derived shell, along with the ZS5 and ZS6. It is of a 4 BA + 1 DD driver configuration, featuring 2 of KZ’s 30095 BA units, a 31005 unit, a 29689 unit, and KZ’s newer 10mm DD unit.


Build and Accessories:

Angular aluminum shell, nearly identical to the ZS6 shell with a slight difference in the angle of the vents on the sides. Very sturdy as one might expect, and comfortable enough – though they may not sit well in some ears due to the large size. Strangely, despite using the same type of shells as the ZS6 and the many color options available for those, the only color option currently out for the ZS7 is black with blue faceplate. The included cable is the newer braided brown style, with standard KZ 2-pin connectors. The packaging on this model is a step up from KZ’s other offerings, complete with an etched metal logo plate, but the accessories are lacking with just a set of silicone ear tips.


Sound:

From the tuning, it’s evident that KZ has learned well from the strengths/critiques of the ZS line. Soundstage and imaging remain respectable – about the best you can get in cheap IEMs, similar to the KZ ZS10. Sibilance issues present in the ZS6 have been resolved, and overall the tuning is much warmer and less fatiguing. Because of this, the highs don’t have the same sparkling clarity, but the result is a much easier listening experience.


Following a slight v-shape curve, the mids are a bit recessed but much more apparent than on older KZ models. As they aren’t fighting a great deal of treble, the detail comes through more easily, picking up a lot of vocal detail. Lower mids on the other hand compete slightly with the bass.


Emphasis in the ZS7 is placed on the low frequencies. Bass is powerful and controlled, making for a very fun listening experience especially in fast paced or busy songs. Sub bass is just right to me, offering a bit of kick without being distracting. On the whole, it’s a very warm earphone.


Overall:

The ZS7 runs about $50 off Amazon, and at that price it’s a great deal given the build and sound quality. It may be worth investing in additional ear tips, as I personally don’t find the stock ones too comfortable. Beyond that though, it’s a fun set to listen to with a tuning that’s hard to go wrong with.

I was provided this product from KZ but I am a fussy user and honest reviewer and often will tell you what I don't like as well as what I like. I like to write a basic and simple review that gets right to the nuggets. If you have time to read reviews that turn into treatises then you will find plenty of other writers on this site who do that.

Background: I have three other pair of KZ earbuds, including some earlier units like that KZ ATE and KZ ES4, both of which I did not especially care for. I do my testing with the manufacturer's cable because I think most listeners will do the same. I do step up and listen through a Pioneer XDP-300R for some testing, as well as just straight from the source Iphone. I listen to all kinds of music including hi res and also stream on TIDAL and Spotify.

As I mention in the headline here, the ZS7 is a substantial step forward for KZ in terms of sophistication of drivers, number of drivers, overall sound, finish and comfort. This is a very good sounding IEM, and even though I am not a huge fan of over-the-ear buds, I have found myself defaulting to these lately with regularity because the sound has grown on me and they are relatively comfortable. And don't kid yourself about comfort friends. You can have the best sounding buds in the world and if they feel like crap in your ears you are not going to wear them. KZ has recently focused on a flatter and more ear-friendly fit. I personally like the memory cable that comes with the KZ ZSN Pro, but the shapeable close-ear section of this unit works pretty well also for wrapping around the top of the ear.

The sound on these babies is pretty terrific. I am not a bass head, in fact I don't like much boom, but the 10mm dynamic driver used for bass on this unit is solid as a rock, deep and not oppressive. It doesn't overtake the mids, but you know it is there. The articulation and tuning of the four other drivers (that's right there are 5!) is excellent. Clean, concise, and natural. I test mostly on vocals, and these things do a terrific job with an unmasked ease on both male and female vocals that compares well to about anything I have heard recently. The highs are able to hit the secret spot for IEMs where they are clean and extended without making my ears bleed with sibilance. This is simply really good tuning by KZ engineers.

Not a huge fan of the braided cable. It is very long from the y split to the ears and I think is prone to tangling, but this is the cable KZ seems to be set on for now and I have learned to live with it. The comfort and overall sound quality of these babies makes up for any other deficiency and I highly recommend them. You will find yourself wanting to hear them more and more as they improve with burn in. I am done.

I received the ZS7 as a review sample of the latest offering by Knowledge Zenith. There were no implications that I should present anything but my unbiased impressions. This was an interesting listen for me as I have, in the past, owned a number of inexpensive Asian in-ear monitors but never one from KZ.

As there have been numerous unboxing photos posted in previous reviews of this phone, and also due to the fact that I am not the greatest photographer, I will forgo duplicating the item by item unboxing shots!

All listening impressions and opinions were garnered over the course of a week on and off sessions. All music was lossless, either FLAC or WAV.

Source equipment varied between the following gear, in no particular order.
Samsung Galaxy S5 using UAPP music player.
FiiO M6 DAP
iBasso DX50 DAP
iBasso DX200/Amp5
Pre Box S2 Digital DAC
Periodic Audio Nickel Amp

Overall packaging was appropriate for gear in this price range and comparable to that of other under $50 phones. Items were neatly arranged and presented an overall positive first impression.

Prior to first listen, I did try to find a suitable pair of tips from the included 3 pairs of silicon tips (S-M-L). Unfortunately, none of the 3 sizes yielded a secure fit with the necessary seal. I did resort to using tips from my stash that worked well with other phones of this general design.

Although the ZS7 is shaped and sized much like the CA Andromeda, I found myself having to adjust the positioning of the phones frequently. I am not sure why, as the Andromeda presented no fitment issues. I suspect that the metal housing might have the majority of their weight on the faceplate side as my movements seemed to loosen them depite my best-fitting tips. Although I began my tests using the included cable, I quick swapped it for several of my own cables as I intensely dislike memory wire! While different cables varied in their comfort, I could tell little difference, if any, in the audio performance.

I began my exploration of this inexpensive IEM with some sine sweeps. The overall profile seemed to indicate that the sub-bass and bass would be the star of the show. The mid-range frequencies seemed to be somewhat recessed in comparison to the bass, with a rise in the upper mids, close to where the female vocals would be heard. This was somewhat forward and when listening to several female vocalists did, in fact, tend toward some sibilance. Higher treble frequencies gradually rolled off making the ZS7 exhibit a moderate v-shaped tonal signature.

Moving on to music from my different sources, I found that my Galaxy S5 was more than capable of delivering satisfying levels of music. The enhanced bass of the ZS7 was, in fact, an asset as typically the early Samsung Galaxy phones were not noted for their bass performance.

I didn't notice a great deal of difference tonally as I moved through my various sources although the sound-stage was most expansive when paired with my DX200. No surprise there. Emphasis on bass does tend to narrow the soundstage as bass and sub-bass frequencies are far less directional than the higher audio frequencies. Given the ability to perform very well without additional amplification, the ZS7 makes a fine daily driver when out and about. The added bass emphasis helps overcome outside sounds making it great for commuting on buses or trains. Not so great for commuting via your bicycle!

I played a number of my favorite test files, including male and female vocals, acoustic, classical and electronic compositions. Although I don't listen to much rock, I always include the ubiquitous "Hotel California" by the Eagles.

Somewhat surprisingly, the ZS7 sounded best to me with orchestral and classical selections. The prominent sub-bass and bass lent a sense of weight to the music which I hear during live performances in a hall. Vocals seemed to be rather hit or miss as the emphasis on sub-bass and bass at times distracted from the vocalist. As the heart of most music typically resides in the mid frequencies, I would have preferred the mids to be more balanced. Maybe a touch less bass. Of course much of the apparent overemphasis of the bass can be the result of less than optimum mastering.

My only other Chinese IEM that I currently own and compared to the ZS7 is the CCA C10. Both are 5 driver hybrids, containing one dynamic driver and 4 balanced armature drivers. They are very different, both in build and in performance. The ZS7 is an all metal, very ruggedly built IEM with a prominent sub-bass and bass emphasis whereas the C10 has a lighter weight mostly acrylic build with a well-balanced SQ that serves as a great all-arounder. If one enjoys hard hitting but accurate bass and sub-bass, the ZS7 is the clear winner. If ones musical preferences lean more toward the acoustic or vocal genres, the C10 would likely prove more satisfying.

Overall, I am always amazed at the performance capabilities of the current crop of sub-$50 IEM's when compared to the performance of more expensive mainstream IEM's of only a few years past.