This is a review and detailed measurements of the Japanese ZERO AUDIO Carbo Tenore ZH-DX200-CT In-ear Monitor. It is on kind loan from a member and costs US $44 from Amazon including Prime shipping. It has been around for a while and seems to have quite a following from scan of online reviews and forum discussions.
"Carbo" apparently refers to carbon fiber look (or is it real) of the body of the IEM:
As you see there is not much strain relief on the wires and what there is, is already split. People complain that the wire is thin but it is actually thicker than the ones on my Panasonic IEMs.
Note: The measurements you are about to see are made using a standardized Gras 45C. Headphone measurements by definition are approximate and variable so don't be surprised if other measurements even if performed with the same fixtures as mine, differ in end results. Protocols vary such as headband pressure and averaging (which I don't do). As you will see, I confirm the approximate accuracy of the measurements using Equalization and listening tests. Ultimately headphone measurements are less exact than speakers mostly in bass and above a few kilohertz so keep that in mind as you read these tests. If you think you have an exact idea of a headphone performance, you are likely wrong!
Fitment on the fixture was a bit challenging at first with one channel having no bass at all. A slight adjustment all of a sudden snapped it into the picture. I used the medium silicone tip for measurements which from experience, fits best on my testing fixture.
Zero Audio Carbo Tenore ZH-DX200-CT Measurements
Let's start with our usual dashboard and special target for IEMs:
Ignoring the kink around 200 Hz which may be a fitment issue, response is remarkably close to target all the way to 3 kHz. Post that energy is too low so likely the headphone will sound dull and lack sparkle.
Distortion unfortunately is rather high in the 2 to 5 kHz where we actually need to boost the response:
Group delay is very clean:
Impedance is very low:
Surprisingly, you need fair amount of drive for these IEMs, worse than some headphones!
ZERO AUDIO ZH-DX200-CT Listening Tests and Equalization
I fit these on my ears and I was shocked how poor the sound was. Not only were there no highs as the measurements indicated, there were no lows either! What the heck? After playing around with EQ for a while and getting nowhere, I decided to adjust how they fit in my ears. Bam! The bass was there and the sound was transformed. I had forgotten that the middle sized tips are too small for my ears. They would only have proper response if I held them manually. Switching to large silicone tips was a revelation. This is why we measure folks. When listening tests are wrong, they put you on warning that you maybe evaluating them incorrectly!
The treble had to be fixed though so out came the EQ tool:
Fitting a filter by eye to the hole there is very challenging. I used two filters but likely an automatic system can generate better fitting. Still, just those two filters were enough to give the much needed excitement to these headphones including providing decent spatial effects. I could listen to them for hours if I did not have to stop to take a picture for this review.
Conclusions
The Carbo Tenore IEMs have excellent bass and mid-range response. While they lack high frequency energy, you may be OK with them and as such, use them without EQ. With EQ though, they become my type of headphone/IEM with excellent dynamics and overall response.
Happy to recommend the ZERO AUDIO ZH-DX200-CT Carbo Tenore IEMs especially with equalization.
-----------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
"Carbo" apparently refers to carbon fiber look (or is it real) of the body of the IEM:
As you see there is not much strain relief on the wires and what there is, is already split. People complain that the wire is thin but it is actually thicker than the ones on my Panasonic IEMs.
Note: The measurements you are about to see are made using a standardized Gras 45C. Headphone measurements by definition are approximate and variable so don't be surprised if other measurements even if performed with the same fixtures as mine, differ in end results. Protocols vary such as headband pressure and averaging (which I don't do). As you will see, I confirm the approximate accuracy of the measurements using Equalization and listening tests. Ultimately headphone measurements are less exact than speakers mostly in bass and above a few kilohertz so keep that in mind as you read these tests. If you think you have an exact idea of a headphone performance, you are likely wrong!
Fitment on the fixture was a bit challenging at first with one channel having no bass at all. A slight adjustment all of a sudden snapped it into the picture. I used the medium silicone tip for measurements which from experience, fits best on my testing fixture.
Zero Audio Carbo Tenore ZH-DX200-CT Measurements
Let's start with our usual dashboard and special target for IEMs:
Ignoring the kink around 200 Hz which may be a fitment issue, response is remarkably close to target all the way to 3 kHz. Post that energy is too low so likely the headphone will sound dull and lack sparkle.
Distortion unfortunately is rather high in the 2 to 5 kHz where we actually need to boost the response:
Group delay is very clean:
Impedance is very low:
Surprisingly, you need fair amount of drive for these IEMs, worse than some headphones!
ZERO AUDIO ZH-DX200-CT Listening Tests and Equalization
I fit these on my ears and I was shocked how poor the sound was. Not only were there no highs as the measurements indicated, there were no lows either! What the heck? After playing around with EQ for a while and getting nowhere, I decided to adjust how they fit in my ears. Bam! The bass was there and the sound was transformed. I had forgotten that the middle sized tips are too small for my ears. They would only have proper response if I held them manually. Switching to large silicone tips was a revelation. This is why we measure folks. When listening tests are wrong, they put you on warning that you maybe evaluating them incorrectly!
The treble had to be fixed though so out came the EQ tool:
Fitting a filter by eye to the hole there is very challenging. I used two filters but likely an automatic system can generate better fitting. Still, just those two filters were enough to give the much needed excitement to these headphones including providing decent spatial effects. I could listen to them for hours if I did not have to stop to take a picture for this review.
Conclusions
The Carbo Tenore IEMs have excellent bass and mid-range response. While they lack high frequency energy, you may be OK with them and as such, use them without EQ. With EQ though, they become my type of headphone/IEM with excellent dynamics and overall response.
Happy to recommend the ZERO AUDIO ZH-DX200-CT Carbo Tenore IEMs especially with equalization.
-----------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
