DUNU EST 112 Review and Measurements

To start, I'd like to say a big thank you to DUNU for voicing this IEM for North American ears. Many of us do not like super emphasized upper mids and spikey highs as prescribed by Dr. Olive's preference targets. The bass is slightly emphasized with the EST 112, but that OK's because everybody wants moar bass. I did eventually dial down the bass on the Loki EQ just a bit. I would also like to thank DUNU for creating something that looks classy. It fact, it's so classy that I let it sit in the opened box (among many others) because I didn't know what I was. Anyway, this is appreciated because I feel that I can wear these IEMs in public. They aren't screaming bright red with winged demons, nor do they look like Fisher Price toys, nor are there stylized lizards with gigantic testicles hanging under their tails. We have a phrase here at SBAF: keep it classy. You guys have certainly done that. And BTW, finding a good fit was super easy with a variety of tips.



I actually did not know that these utilized electrostatic drivers. I guess this is a DD, BA, EST hybrid. Integration of the different drivers types sounded pretty good in the crossover areas. However in the end, I felt the sound of the drivers was simply too different. The DD lows carried heft and physicality, were well textured, but were a bit plodding and thick. The balance of the midrange was good, maybe just nick more volume with the pinna gain spot pushed just a slightly higher in frequency than I would like - but close enough. The timbre of the mids and upper mids sounded very stereotypical BA, which tended to dominate over the electret drivers in the highs. I kind of wished I could have heard the sound of the electrets more to themselves without the BA drivers getting in the way.

Readers should note that these are not "true" electrostatic drivers which require a high voltage bias on the diaphragm. If they were, they wouldn't be able to work like this. Instead, a charge is impregnated on the diaphragm while an internal transformer multiples the voltage so the stators can move the diaphragm. I assume this is why the body of the EST 112 is fairly large. There needs to be room for the transformer. Also, I should point out that in my experience, electrets have never quite sounded like real electrostats. They do get close in terms of speed and transient response, and oftentimes that's good enough. However, electrets do have their own sound. If anyone is looking for that Shure KSE1200 experience, then this isn't it. The KSE1500 wasn't that special to me anyway and was rife with some issues which I feel this three-way hybrid approach has addressed - read here.

DUNU EST 112
Frequency Response


NOTE: There's slightly more bass than what is measured here. My IEM coupler isn't an a IEC spec with the proper air impedance simulation. As such, I believe that it underreports the bass for DD type drivers. This does not affect BA type drivers.

 

Other impressions:

• https://www.superbestaudiofriends.o...sions-and-discussion.10501/page-2#post-342796
• https://www.superbestaudiofriends.o...sions-and-discussion.10501/page-3#post-349547
  
• https://www.superbestaudiofriends.o...sions-and-discussion.10501/page-3#post-350148
  
• https://www.superbestaudiofriends.o...sions-and-discussion.10501/page-3#post-352534
  
• https://www.superbestaudiofriends.o...sions-and-discussion.10501/page-3#post-353619

 

DUNU EST112
Distortion level by harmonic vs. frequency at various SPL


Distortion seems to be on the high side. I felt thought with a three-way using different drivers, we'd see the best of all. Unfortunately, it would be that we are getting some of the worst of all. I would maybe expect third order to be a bit higher where it usually is in the mids, but low in the bass. To some extent this is true, at least until we really crank it up. I I think the most concerning the highish third order in the middle to upper mids - where I mentioned I heard an unmistakable BA pervasiveness that dominated other the electret driver. Second, third, and fourth harmonics are a bit at a spot in the upper mids too. Distortion tends to drop down from lower treble upward. This is where I felt the EST112 was nice. A nice smooth delicate highs not anything at all like the BA driver sound. Perhaps maybe a bit too much as @rhythmdevils felt the highs were a bit papery. Still, the highs are different.

I don't know if the xover points are different, if there is any xover, or if the slope is too shallow. I do wonder if that distortion peak is a result of those electret drivers being pushed too hard too low.

At the end of the day, despite the EST112 having a significantly more amenable frequency response to the single driver DD DUNU ZEN, I felt the DUNU ZEN was better in technicalities. Better at resolving fine details, more lively, clearer. DUNU ZEN distortion plots below for apples to apples comparison.

DUNU ZEN (for comparison)
Distortion level by harmonic vs. frequency at various SPL

 

DUNU EST112
Impedance and electrical phase


Impedance is fairly flat and doesn't vary all that much. Stays between 7.5 and 12 ohms with most of it flat up to 1kHz.

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I applaud DUNU for taking the risk, to quickly jump into ESTs so we can get a taste, and for the very good tonal signature. However, I don't think the EST112 is totally ready for prime time yet. The technicalities fall sort of the ZEN, the cohesiveness is behind both ZEN and SA6. The distortion is a bit high. And really, I want to hear more of that electret driver without the BA in the way. I don't know if it's possible get just get rid of that BA driver all together because it sticks out that like a sore thumb. At the end of the day, there are better hybrids, but they also do cost two to three times more. The EST112 does do anything horribly wrong. I don't know if I am being reasonable if I said I simply wanted it to more things extremely well.