Kz as10 review: finally

Overview of Balanced Armatures and Dynamic Drivers

This section is a standard inclusion in my hybrid IEM reviews.

In-ear monitors (IEMs) use either Balanced Armatures (BA) or Dynamic Drivers (DD) to produce sound.

Dynamic drivers are what you think of when you picture a loudspeaker. A voice coil is attached to a moving diaphragm to move air and produce sound. DDs are tried and true, durable and cheap.

A single DD can cover the entire frequency range without a crossover and is capable of extended bass response.

While traditionally used in hearing aids, BA drivers are tuned to work in a specific range of frequencies. A crossover circuit is used to split the signal to multiple BA drivers covering multiple frequency bands.

BAs are considered balanced because the design features a coil around an armature suspended and centered between two magnets.

They are smaller than traditional dynamic drivers and tend to better treble performance with speed and detail, but often sacrifice bass performance. Since multiple BAs are required to cover a wide frequency range, they are typically more expensive.

Hybrid IEMs combine DDs and BAs in a single housing in an attempt to capitalize on the benefits of both designs.

Final Thoughts

It is a bit of a shame that KZ opted for such a bad design from a comfort perspective, because the KZ BA10 are really great when it comes to sound. They are not as balanced as the AS10, but they counter that with incredible technical prowess. They are astonishing in their technical ability, considering the price bracket they are in. Bass depth and punch, detail, soundstage and instrument separation are all elements that set these earphones apart from KZ’s production – and in a very good way.

The only real downside of the BA10 is their design that makes them incredibly uncomfortable. Were it not for this fact, they could easily be the best earphones made by KZ alongside the AS10 (which come out as the best because of their comfort, given their similar sound signature). It’s a missed opportunity in this sense, but they are absolutely worth a shot if you can live with a bit of discomfort or if you find yourself comfortable with their shape.

Packaging and Accessories

Unlike the larger black display boxes included with the BA10 and AS10 models, the KZ ZS10 Pro uses the more common, small white KZ box design. A white cardboard box slides out from a thick paper sleeve, topped with a thin clear plastic cover. It’s small, simple and works fine, but doesn’t convey an intrinsic sense of quality.

The simple white KZ ZS10 Pro box compared to the more premium AS10 package

No fancy (but ultimately useless) metal name plates (as per the BA10 and AS10) are included. Nor case, nor storage bag, nor adapter, nor much else. Just 3 spare ear tip pairs (small, medium and large), a detachable cable, a safety and instructions guide and a 12-month warranty card. The bare minimum of what is expected these days.

Cable

Let’s get this out of the way first: contrary to popular opinion, I actually like KZ cables and think they are well designed and nicely made. I like the 2-3 inches of stiff memory wire at the IEM pin end that holds its shape around the top of the ear. I find it works well and is perfectly comfortable once shaped to your particular head.

The included non-microphone cable

The KZ ZS10 Pro’s cable appears to be much the same as the detachable, bronze colored, braided cable included with the AS10 model. I find it minimally microphonic and nicely flexible.

The standard 90-degree black rubber 3.5 mm TRS jack and simple black rubber Y-splitter are customary KZ. Nothing especially fancy, but it looks and feels reasonably premium. My only real complaint is that the Y-splitter is located about 50 mm down the cable. Personally, I’d prefer it 15-20 mm higher up.

The angled, gold-plated, IEM pin connections are 0.75 mm in width (the usual from KZ). However, the jack adds yet another variation to their lineup (in addition to the straight and other angled version). The pins are recessed in the cable connector, while the sockets protrude from the IEM body. Only the ZSN and ZSN Pro currently use this design.

The connectors on the ZS10 Pro cable

I think the new cable pin setup creates the most secure connection of all the KZ options. Let’s hope that this becomes the standard used on all models going forward.

Lack of standardization punishes customers who purchase aftermarket cables and want to use them with more than one pair of IEMs.
The new cable connector design

Ear Tips

These IEMs only come with the stock KZ star-patterned, black ear tips in small, medium and large sizes. No foam tips are included. The good news is that they are relatively comfortable, work as expected and provide decent isolation and a good seal. KZ claims 26 dB of noise reduction.

As seems to be the case with KZ, I found the large size to work best for me, although I typically use medium-sized ear tips with other IEM brands.

The standard KZ black ear tip.

Документация ›› Рекомендации по повышению надежности работы устройств РЗА, находящихся в эксплуатации

1. Для выполнения  п. 5.9.13. ПТЭ во избежании перекрытия изоляции рядом находящихся выводов промежуточного клемника, необходимо усилить изоляцию промежуточных клеммников  панели ПДЭ 2006 (ДЗО 330 кВ) путем установки дополнительных козырьков из изоляционного материала на промежуточные  клеммники. При проведении технического обслуживания панелей серии ПДЭ проверять монтаж и пайку проводов панелей.  Желательно выполнять рекомендации ОДУ Сибири, а именно — обязательно «сдвигать с места» регуляторы переменных резисторов для разрушения возможно имеющейся непроводящей пленки с последующей проверкой характеристик. При этом, резисторы, где обнаружен ненадежный контакт, заменить на исправные.

Design & Comfort

Contrary to packaging, where the exterior changed and the contents didn’t, the change in the innards of the earphones is not followed by a change in appearance. The KZ AS10 are in fact almost identical to the KZ ZS10, both in shape and materials. The AS10 is slightly more triangular and smaller, but that’s about it. Even the transparent faceplate that shows the coloured PCB is identical. So if you did not like the design of the ZS10, you may want to skip this one too.

The only news is that the plastic that makes up the rest of the housing and the nozzle is black. The grille is not on top of the nozzle, as it usually is, but it is inside – an odd choice that leaves the dirt free to enter the nozzle and makes it difficult to remove it once it’s in.

Comfort is indeed good and better than I expected; considering the similarities with the ZS10, I thought it would be decent but not that great for long listening sessions. Truth is, I used them all day long for multiple days and only got some fatigue at the end of the day. The AS10 is therefore an IEM you can rely on when it comes to comfort. As subjective as comfort is, I think the KZ AS10 is much more universal than other headphones as it is small and light – so take my thoughts with a pinch of salt, as usual, but also consider the fact that they’re really one of the best IEMs by KZ in terms of comfort.

Like the ZS10 before it, the AS10 does not offer a high level of passive isolation from external noise, providing just a bit of reduction in volume and not much more. Using foam tips helps reduce noise a bit, but they can’t replace the isolation that the shells do not offer.

The cable is the same KZ started shipping with the KZ ES4 – a four-core, braided cable with a brown tint that looks and feels better than the previous flimsy ones, but is not yet that good. It has high microphonics, so it is not really recommended for walking or running unless you use a clip.

Design & Comfort

I don’t know who thought of the BA10’s design, but I would surely like to have a word with them. While it is certainly original and new, and a good step away from the shameless copying we saw with the ZS5 and ZS6, it is not practical at all. It is squared and full of clear-cut edges that cut into one’s ears like a hot knife through butter. Okay, it’s not exactly like that, but you get the idea.

The design is in fact bold and innovative and this is laudable. KZ is trying to shed off the copycat image it created for itself, so trying new designs is a good thing for both them and the consumers. The choice of colours is debatable, though, as the red and gold colour scheme chosen for this unit is a bit of an eyesore. That’s up to one’s preferences, as usual, but I would sure have appreciated more sober colours (though a black and red variant exists, too).

Getting the earphones on is a challenge in itself to say the least. On top of the bizarre design that makes wearing the earphones awkward (if not outright painful at times), the shape of the shells itself makes it difficult to wear them. The squared shapes, coupled with the nozzle that is not angled, make wearing the KZ BA10 a bit of a hassle. In order to get them in I have to pull the lobe down, push the earphones in and then moving the pinnae and the earphones around until I get a good fit. It’s not a good experience, even less a simple one.

Even once you get them on, the experience is not the best one could dream of. Quite the contrary, in fact: the clear-cut edges, as I have already mentioned, are the largest pain point (literally!) of the KZ BA10 as they make it impossible to wear the earphones for long periods. I personally start to feel discomfort after just a few minutes, and in half an hour that becomes plain pain. This is personal experience that can in no way be generalised, but the shapes lead me to believe that very few people – if any – can find the shells comfortable.

All of this happens regardless of the tips I use, and is true even when using fairly large foam eartips. There is a clear comfort issue at play here. Having that said, I think that the lack of isolation that the KZ BA10 have is at least partially related to this. The BA10 can’t in fact reduce outside noise effectively, making it almost impossible to use them in busy (or anyway noisy) places without raising the volume dramatically.

KZ opted for their usual flimsy cable, although it is not coloured and therefore it exposes the natural hue of copper. It’s not really a good cable, at least after the Y split: the cores are rather flimsy and braided so that they are very prone to kinks; in addition to this, there is a metal rod that gives the cable a shape around the ears, but it is too stiff to be truly comfortable.

The Challenge of In-Ear Monitor Reviews

This section is a standard inclusion in my IEM reviews.

I’d like to add a caveat. IEMs are notoriously difficult to review and compared to full-size headphones, it is problematic to trust that review findings will be applicable to all readers.

While the size of one’s ear may impact comfort or sound of a full-size headphone, small details like the inner shape of a reviewer’s ear and the fit of an IEM greatly impacts not just the listener’s comfort, but dramatically changes the perceived performance of an IEM.

This is compounded by the plethora of ear tip sizes, materials, and shapes (which may or may not be included with the IEM), all of which uniquely fit different people. Most significantly, the quality of the ear tip seal within the ear changes the sound. So, beware dear reader, what suits one reviewer may not be applicable to you.

Conclusion

Perhaps practice does indeed make perfect. KZ started by making ‘cheap’ (forgive me) but fun IEMs that sold very well. So they made more. A lot more. They transformed and progressed. Successive models have certainly improved sound quality with a modest increase in price. Not every model is a home run, but things have been moving steadily in the right direction.

It sure looks like KZ must listen to the feedback they receive and put that knowledge into new product design. The recent top of-the-line AS10, BA10 and now the ZS10 Pro models are displaying this evolution from ‘fun but cheap’ to ‘good sound at a moderate price’. Chi-fi is beginning to mature and KZ continues to be at the front of the pack.

Stunning HIFI configuration.

The ZS10 Pro is a great IEM. It isn’t a scalpel for critical listening. Nor is it a bass cannon for the ‘only-EDM’ crowd. It doesn’t have to be. Paired with rock, pop, blues or anything with a back beat, it gets your toes tapping and your head bobbing. Success in my books.

Long live ZS10 Pro the king!

So yes. The KZ ZS10 Pro is my new favorite IEM from KZ. Sorry AS10, you weren’t the king for very long.

Long live the new (better looking and more fun) king!

Final Thoughts

I am quite surprised by what KZ achieved with these earphones. The KZ AS10 are amazing in their own way: their tuning is balanced and enjoyable, there’s a very good technical level and they’re comfortable. They’re not perfect, though, as there’s still some work the tuning could see – a bit more clarity with a slight emphasis on the upper midrange and more treble extensions would make them even more interesting.

If we look at them from a perspective of balance and adherence to an ideal neutral sound reproduction, the KZ AS10 are the best headphones made by KZ so far. As they are also competent on the technical side, they have my full recommendation – KZ charges a premium for the AS10, but it’s worth it.

Файл-архив ›› Инструкция по наладке и проверке устройств фильтр-реле тока обратной последовательности типов РТ-2 и РТФ-1

В данной инструкции по наладке и проверке устройств фильтр-реле тока обратной последовательности типов РТ-2 и РТФ-1 приведено их описание и принцип действие, схемы включения, порядок проведения полного объема проверок начиная от внешнего осмотра, проверки изоляции, настройки фильтр-реле и заканчивая проверкой реле током нагрузки.

В приложениях приведены полные технические характеристики фильтр-реле РТ-2 и РТФ-1, заводские калибровочные таблицы и типовые протоколы для проверки обоих типов фильтр-реле.

Инструкция по наладке и проверке предназначены для персонала служб РЗАИ энергетических систем и наладочных организаций, занимающихся вопросами наладки и эксплуатации устройств РЗА в которые входят фильтр-реле тока обратной последовательности типов РТ-2 и РТФ-1.

Файл-архив ›› О предотвращении излишних действий защит ДФЗ линий 110-500 кВ при внешних КЗ. Циркуляр № Ц-04-94(Э) от 30 декабря 1994 г

Циркуляр № Ц-04-94(Э) от 30 декабря 1994 г.

О предотвращении излишних действий защит ДФЗ линий 110-500 кВ при внешних КЗ.

В ряде энергосистем на линиях 110-500 кВ имели место случаи излишней работы дифференциально- фазных защит ДФЗ-201, ДФЗ-401, ДФЗ-402, ДФЗ-501, ДФЗ-503, ДФЗ-504 при отключении внешних коротких замыканий (КЗ) защитами смежных линий. Анализ осциллограмм таких отключений в Иркутской и Свердловской энергосистемах показал, что при отключении поврежденного элемента сети в токе приема защиты ДФЗ неповрежденной линии в некоторых случаях появляется одиночный импульс, достаточный для срабатывания органа сравнения фаз ДФЗ и ее отключения. Как выяснилось, причиной излишнего действия защиты ДФЗ является некоторое различие характеристик блоков манипуляции, их устройств компенсации емкостных токов, а также трансформаторов тока по концам линии, что в условиях переходного процесса в сети при отключениях КЗ вызывает в совокупности кратковременную неидентичность переходного процесса на выходе блоков манипуляторов, от которого не отстроены указанные защиты, имеющие быстродействующие выходные реле.

Build Quality

To say the KZ ZS10 Pro is merely attractive does them a disservice. The design is highly reminiscent of the ZSN and ZSN Pro. The mirror-finished, stainless steel faceplate is simply gorgeous, albeit prone to fingerprints. It is held on with three tiny star-shaped screws, features three tiny round ports and has three engraved accent lines. “10 Hybrid Technology” is written on the plate’s beveled edge.

On a Mushroom!

The body is made of a colored, semi-transparent plastic, which displays the plethora of drivers and wires contained within. Fit and finish are superb and the body to faceplate mating is spot on. “KZ-ZS10 Pro stunning HIFI configuration” is printed below the faceplate writing. The nozzle is a brass colored aluminum alloy tube, ridged on the end to hold the ear tip and contains a small silver screen.

I’m hoping the screen within the nozzle is more firmly attached than the similar screen in the BA10. I’ve found that the screens in the BA10 dislodge fairly easily with minimal usage. A VERY concerning issue as this could fall out within the ear canal!

This is a fantastic looking IEM, certainly a standout at its price point, and quite simply far and away more attractive than the AS10 model. The all-plastic design of the AS10 is comfortable, but I am just not a fan of how that IEM looks. The ZS10 Pro is equally as comfortable and much better looking.

Driver Configuration

Each IEM uses two KZ 30095 BA drivers for high frequencies, two KZ 500060 drivers for midrange frequencies and a single 10 mm Tesla double magnetic dynamic driver for low frequencies. A tiny PCB frequency dividing board (crossover) resides inside to split the appropriate signals to each driver.

The driver layout

One of the high-frequency drivers is located in the tip, rather than in the body of the IEM, which means it is closer to, and more directly pointed at the eardrum. This is similar to the version 1 design of the ZS5; version 2 placed both high-frequency BAs in the tip. A common complaint is that this change made the sound too piercing and sharp compared to the v1.

The balanced armature design

KZ claims that the high-frequency drivers are capable of reproducing frequencies beyond 40,000 Hz. Since this is far outside the human hearing range, we will have to take their word for it. Here’s what KZ has to say about the dynamic driver:

“Second generation Tesla double magnetic dynamic. The driving force is twice the conversion efficiency of the normal dynamic. Compared with the ordinary single magnetic dynamic, the electroacoustic efficiency is obviously improved. Reproduce strong bass at any time and restore the low frequency details of the majestic.”

Well, I don’t know about all that, but a benefit of using a dynamic driver (rather than a BA) is to achieve extended low bass response. So, compared to an all balanced armature design like the AS10, the KZ ZS10 Pro should be able to dig a bit deeper. Let’s talk about how they sound next.

Файл-архив ›› Инструкция по наладке, проверке и эксплуатации панели дистанционных защит ПЗ-З/2 И ПЗ-4/2

В инструкции дано подробное описание конструкции и принципов выполнения панелей дистанционных защит ПЗ-3/2 и ПЗ-4/2, выпускаемых Чебоксарским єлектроаппаратным заводом. Изложена методика наладки панелей защит ПЗ-3/2 и ПЗ-4/2 при первом включении и периодической проверке, приведены рекомендуемые схемы для снятия характеристик защит при отсутствии комплектных испытательных устройств, даны рекомендации по выбору уставок. В инструкции в качестве приложений приведены технические данные элементов защит, а также назначение отдельных указательных и промежуточных реле, накладок и перемычек.Инструкция рассчитана на работников энергосистем, эксплуатирующих дистанционные защиты ПЗ-3/2 и ПЗ-4/2.

KZ Overview

KZ was founded in 2008 by classical musician Zen Li and former Audio-Technica engineer Keith Yue. It is a public brand for the Shenzhen Yuanze Electronics Company located in Guangdong China.

KZ has generated a huge amount of industry buzz by creating products that have seriously redefined the ratio of price to performance. There has been seemingly unending hype over KZ (as of writing: almost 3000 pages in a single Head-Fi post). The caveat? Most discussions conclude with the idea that although their IEMs may not produce the absolute best sound, they are difficult to beat at the low price point.

Recently, some of their models which are more technologically advanced and offered at slightly higher price points have elevated the brand as a mainstream competitor. However, KZ has received criticism for copying the design and form factor of high-end models from Campfire Audio and Audio-Technica.

KZ IEM Series

KZ is also known for releasing many different models, so it gets convoluted when trying to figure out their hierarchy of IEMs. In a nutshell, the KZ offerings include the following series:

• AS – AS6, AS10 (balanced armature drivers – # denotes total drivers)
• AT – ATE, ATES, ATR (single dynamic driver)
• BA – BA10 (balanced armature drivers – # denotes total drivers)
• BT – BTE (hybrid BA and dynamic drivers – Bluetooth)
• ED – EDR2, ED4, ED7, ED9, ED12, ED15, ED16 (typically a single dynamic driver – ED15 and ED16 are hybrid)
• ES – ES3, ES4 (hybrid – 1 BA + 1 dynamic driver)
• HD – HDS3, HD9 (single dynamic driver)
• ZS – ZSA, ZSE, ZSN, ZSN Pro, ZSR, ZST, ZST Pro, ZST Colorful, ZS1, ZS2, ZS3, ZS4, ZS5 (v1 and v2), ZS6, ZS7, ZS10, ZS10 Pro (ZS1-3 and ZSE are dual dynamic driver, other ZS are hybrid)

Whew. I tried to warn you.

Currently, 5 drivers per IEM are in KZ’s top of the line models. You’d swear that 5 drivers per small IEM is an impressive enough feat of engineering, but the AS16 with (you guessed it) 8 drivers per side was recently announced. Unfortunately, more isn’t always better in the KZ lineup, so I look forward to hearing them myself.

To keep things as simple as possible, let’s assume the AS10 is the model to beat for sound quality, comfort and quality. Let’s see how the ZS10 Pro stacks up to my current KZ favorite.

Основы релейной защиты ›› 3-4. Максимальная токовая защита нулевой последовательности от КЗ на землю одиночных линий 110 кВ распределительных сетей

РАСЧЕТЫ ЗАЩИТ ОДИНОЧНЫХ ЛИНИЙ 35 И 110 кВ

Общие сведения. Максимальная токовая защита нулевой последовательности реагирует на однофазные и двухфазные КЗ на землю, общее число которых составляет около 85 % всех КЗ в сетях ПО кВ. Токовые реле этой защиты включены в нулевой провод полной звезды трансформаторов тока линии или на трансформатор тока в заземленной нейтрали 110 кВ силового трансформатора, где в нормальном симметричном режиме протекают только токи небаланса. Токи срабатывания защит от КЗ на землю поэтому не нужно отстраивать от токов перегрузки, как это требуется для максимальных токовых защит от междуфазных КЗ (§ 1-1), и, следовательно, они могут обладать высокой чувствительностью к удаленным КЗ на землю .

Файл-архив ›› Программа « Расчет токов КЗ в сети, питаемой от свинцово-кислотных аккумуляторов»

Программа разработана на основании ГОСТ 29176-91.    При использовании свинцово-кислотных аккумуляторов типа СК расчет производится с учетом зависимости разрядного тока от продолжительности КЗ (от 0 до 0,6 с). Расчет производится с учетом электро-химических процессов, происходящих в АБ. Ток КЗ определяется при «металлическом» КЗ и КЗ «через дугу». В качестве исходных данных задается следующее:

• • Тип аккумулятора («СК») и его номер (окно «АБ-ЩПТ»)
  • число элементов АБ (окно «Перечень расчетных схем»);
  • номер типа СК (окно «Перечень расчетных схем»);
  • геометрические параметры пластин аккумулятора (окно  «Аккумуляторы типа СК»);
  •  внутреннее сопротивление одного аккумулятора СК-1 (независимо от того, какой номер СК используется), (окно  «Аккумуляторы типа СК»);
  • начальная относительная плотность электролита (окно «Электролит»);
  •  электрохимические константы (окно «Электролит»);
  •  данные схемы замещения рассчитываемой сети.

Файл-архив ›› Панели защиты ЭПЗ 1638- 73 и ЭПЗ 1639- 73. Техническое описании и инструкции по эксплуатации

В даном техническом описании и инструкции по эксплуатации панелей защит типов ЭПЗ 1638-73/1 и ЭПЗ 1639-73/1 приведено описание принципа действия комплектов защит, их технические характеристики, меры безопасности при выполнении робот и рекомендации по монтажу, наладке и эксплуатации устройств. В приложении к инструкции прилагаются монтажные и принципильные схемы комплектов защит.

Назначение защит. Панели типов ЭПЗ 1638-73/1-У4.2, ЭПЗ 1639-73/1-У4.2, ЭПЗ 1638-73/1-Т4.2, ЭПЗ 1639-73/1-Т4.2, ЭПЗ 1638-73/2-У4.2, ЭПЗ 1639-73/2-У4.2, ЭПЗ 1638-73/2-Т4.2, ЭПЗ 1639-73/2-Т4.2 предназначены для продольной дифференциальной токовой защиты линий 110-220 кв для исполнения в качестве основной защиты. Панели типов ЭПЗ 1638-73/1 и ЭПЗ 1639-73/1 предназначены для защиты одной линии, а панели типов ЭПЗ 1638-73/2 и ЭПЗ 1639-73/2 для защиты двух линий. Панели типов ЭПЗ 1638-73 и ЭПЗ 1639-73 устанавливаются по концам защищаемых линий и соединяются между собой вспомогательными проводами. Для осуществления продольно-дифференциальной токовой защиты одной линии на каждой из панелей устанавливается полукомплект комплекта защиты типа ДЗЛ-2.

Основы релейной защиты ›› 1-7. Расчеты релейной защиты от междуфазных КЗ на электромеханических реле для воздушных сетей 6 и 10 кВ в сельской местности

Общие сведения. В сельской местности электроснабжение осуществляется, как правило, по воздушным линиям (BJ1) напряжением 10 и, реже, 6 кВ, которые подключаются к подстанциям с высшим напряжением 35 или 110 кВ, а иногда и более высокого класса напряжения. Благодаря сооружению большого числа питающих линий и подстанций 35, 110 кВ во всех сельскохозяйственных районах нашей страны значительно снизилась средняя протяженность линий 10 (6) кВ. Появилось много сравнительно коротких линий (до 10 км), но наряду с ними сохраняется еще значительное число BJI 10 кВ, протяженность которых исчисляется десятками километров, а также таких BJI 10 кВ, которые могут значительно удлиняться при создании кратковременных аварийных и ремонтных схем электроснабжения.

Sound Quality

Post any pictures of a new KZ product online and you will be inundated with questions along the lines of, “how do they sound compared to this KZ model?”. Everyone is interested in how the newest release sounds. The front of the box says that it features “high sensitivity treble and powerful dynamic bass”. Who am I to argue?

Frequency response graph

I listened to the ZS10 Pro with a variety of sources, including an iPhone dongle, a Little Bear B4-X portable tube amp, a JDS Labs C5D and a Pete Millett NuTube hybrid desk amp. It is extremely easy to drive and honestly don’t benefit much from powering them on anything beyond the iPhone. Just what I’m looking for in portable IEMs.

The characteristic KZ v-shaped sound signature is still there. Somewhat. It’s actually nicely balanced, like the AS10 and BA10, without crazy piercing highs or an anemic midrange. Bass is somewhat elevated (which to me means ‘fun’ sounding), mids are oh-so-slightly recessed and the treble is nicely rolled off before things get sharp.

Combined with being very comfortable, the ZS10 Pro is an easy IEM to listen to for long sessions, and a delight for anything with a back beat.
On an interesting mushroom.

Bass

Love it. The low end is tight, deep and controlled. It sounds fuller than the “all BA” AS10, but remains clear and taut. I didn’t experience any bloating or bleed into the midrange. The IEM gives plenty of depth, but not at the expense of becoming unbalanced with how rest of the audio range is presented.

Midrange

The mids are consistently laid back and never shouty. Voices sound natural and timbre overall is quite good. Possibly a bit more elevation in the mids would blend the frequency extremes together a little more. I (perhaps psychosomatically) sometimes felt like I could tell there are multiple drivers creating all those sounds, rather than hearing a perfectly uniform presentation from a single source.

Treble

Compared to the AS10, the treble in the ZS10 Pro comes across as slightly more rolled off. This tends to make the overall sound a bit warmer, and avoids any harshness or brittleness in the high end. Coupled with the deeper lows, this really moves the sound into my preferred zone.