Review - Kiwi Ears Allegro

Review - Hifiman TWS600

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Also available on YouTube in Spanish: Acho Reviews YouTube 

Let me first say that the TWS600 were very kindly sent to me by Hifiman for review. They haven’t requested anything in exchange for sending them to me, in fact, they haven’t even requested that I actually post a review, they just wanted to help out with the launch of my new YouTube channel.

Now, I would like to point out that I will continue to be unbiased in my review of this (and any other product I may receive for review) but it is obviously worth noting that these have not cost me anything money wise to be able to test them out, so take that as you may.

At the time of publishing this review, they are available directly from Hifiman for $69, which is a big reduction from their original price of $199, and makes these much more of an interesting option at that price. There is a trend of TWS IEMs at the moment and while I have tried a few (and I some others incoming for review), this is the first time I have spent any considerable time with a set.

Build and comfort...

The IEMs themselves have a very futuristic look to them and, while the charging lights are on, they look as though they could have been taken directly from a Sci-Fi movie. This will appeal to many people and probably not appeal to others. Personally I like them. They are not the smallest TWS set available but they are not so big as to be considered bulky.

The IEMs came with the charging case, a USB C cable for charging the case and a large variation of tips (more about tips in a moment). As with most TWS IEMs, the case is used to recharge the IEMs when not in use, increasing the use time by a considerable amount, which is already pretty good as it is.

However, one of the issues with the case is the size of the cutouts where the IEMs sit for charging. These are pretty small and if using larger tips on the TWS600, this can cause issues with them charging correctly and even closing the case.

The IEMs are completely made of plastic, which is to be expected, and are pretty lightweight for their size. Once they are seated correctly in my ears, using foam tips, I do not feel any additional discomfort in comparison to other IEMs that I am used to using.

The thing to note there is that I said “using foam tips”, which is a bit of an odyssey itself due to the fact that these IEMs change their sound dramatically based on tips. I will explain more under sound but let's just say that I found the best sound to be while using the triple flange tips, however, I also find those tips very uncomfortable and cannot stand them in my ears for more than 10 to 15 minutes.

In general I have no complaints with the build quality of the TWS600 or the looks of it (which is obviously personal taste), I think that they seem to be generally well built for a set of TWS IEMs at this price point, especially with the Hifiman name on them.


Now, I want to preface this section by saying that I have had issues with my phone (Xiaomi Redmi Note 4) and the TWS600. I believe that this is completely related to my own personal phone and not the actual model of phone or IEM. Using a Lenovo Tab 4, or PC, I have not had issues, so my comments are based on using them with the Lenovo Tablet and with a laptop.

The connectivity of these is great. They are quick to establish a first connection and are almost instant when reconnecting after charging. At no point did I lose connection and I can’t confirm if the range of 150m claimed by Hifiman is correct but I can confirm that I moved all around my office, outside in the workshop, as far as the other end of the warehouse and even upstairs to another office and had no connection drop outs, that is pretty impressive.

The IEMs offer the same basic functionality as most other TWS sets, with a single click (on either side) to pause/unpause, a double click for next (right) and last (previous), and a triple click for volume up (right) and volume down (left). Holding the button for a few seconds activates the voice assistant.

I did have a few weird occurrences here though, as sometimes (it happened 3 or 4 times, both on the tablet and on my PC) after connecting the next and previous functions would be reversed, with the left side doing next and the right side previous. At first I thought it may be due to me pulling them out of the case in the wrong order, however, the volume function always worked correctly (right up and left down) so I am not sure what happened there. A quick reconnect cured the issue.

One thing to note is that the button for these functions is placed in the center, almost exactly over the point where the IEM is inserted into your ear. This means that when pressing the button, you are also pressing the IEM into your ear, which can be very uncomfortable if using the triple flange tips for example, as the tips extend far into your ears.

Other things to note about functionality is that once connected to an Android device (I have no idea about Apple, sorry), the device will show the remaining battery of the IEMs. It is also possible to use them in a mono set up by just removing one IEM from the case.


Here is where it started getting a little… different.

When I first put them on, completely ignoring the card included in the box from Hifiman saying “Do not judge before 20 hours of burn in”, I found them to sound very strange. The mids were very exaggerated, with not much else, to the point of being painful at times.

I decided that I would follow the advice from Hifiman, so I connected them to my tablet and played music through them for more than 20 hours before trying again.

After the burn in, they did sound very different to my first experience, in a much better way (which wasn’t difficult ;) )

But this is where the tip rolling started.

I literally tried every tip that Hifiman included in the box, along with many other tips I had available, and the sound was different with every tip, although there was a consistency to the signature of the sound.

The TWS600 are a very mid centric IEM, that seems to be their focus as an overall sound signature. Playing around with the various tips made changes in the bass and treble ranges without ever losing that mid-centric sound.

The mids are well done and it shows that Hifiman seem to have aimed for this sound signature on purpose, as they do not seem to be getting it wrong, it is just aimed towards a sound signature that I am not used to.

The triple flange tips did bring up the bass amount considerably, although still rolled off in comparison to the mids, to a quantity that I would consider acceptable for a lot of vocal music that doesn’t need much bass, however, due to the fact that I found these tips so uncomfortable, I couldn’t spend the time necessary to give a detailed opinion on the IEMs with the triple flange tips.

With the foam tips, I did spend a lot more time listening and working through my test list and other combinations an genres of music. However, with these tips, the music was very mid centric, and I personally found them fatiguing.

To give an general idea of how these sound (without the triple flange tips), they reminded me of the sound signature that Bose was so fond of with their speakers up until some years ago. I was never personally a fan of that sound but obviously not everyone would agree as Bose made itself into a household name based on that sound signature.

If you are someone who likes a lot of bass and sub bass rumble, this is not something that you will find with the Hifiman TWS600. Instead you will find a sound that is clearly intelligible, throughout the whole vocal range. This actually makes them very good for calls, conferences and even video consumption, although they are not my preferred signature for music listening.

I also feel that the lack of codecs available play a big part in the final listening experience, as they only use AAC and SBC codecs.

As far as the microphone quality, I didn’t get to use it too much due to the issues with my phone, but for the few conferences I used the TWS600 on, the reports from the other end was that it was satisfactory.


I know that this review is lacking in details about sound and my usual references to songs or genres, but to be totally honest and blunt, I didn’t enjoy them that much for listening to music and I couldn’t cope with the triple flange tips for long enough to give a coherent review (although that is obviously a personal comfort issue).

The commodity and convenience factor is obviously there, making them very easy to grab out of the case and just connect, so for someone who wants something that can easily be carried around with a good battery life and is always available for quick calls (or not so quick calls) then these will certainly fit the bill.

As they are IPX4 rated, they are also a good option for sports, as long as those sports aren’t under water of course. I think that they would work well in a gym situation, with the long range and great connectivity, you could leave your phone in your bag in the locker and just wear the IEMs. Although, if you are strongly into bass while training then maybe these would be a little lacking in that respect.

For video consumption, I also think that they are a good option. If you are someone who watches a lot of YouTube videos, or shows etc., while on the move, then these could serve you well as you will never find yourself having to rewind to see what the person said. Oh, did I mention these can get extremely loud? As in, way louder than I could ever see anyone needing. I used them a fair bit for YouTube content and was happy with the results.

So, although I am not a fan of these IEMs for music, I do think that they have certain traits that would work very well for some people.

Again, many thanks to Hifiman for sending these to me for review, it is much appreciated!

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