- May 28, 2020
- French, leaving in China
This is a review and detailed measurements of the 1MORE Quad Driver "THX Certified" IEM. It is on kind loan from a member and costs US $150.
View attachment 205334
I must say this is one excellent work of packaging! The little carrying box has magnetic flap which is nice. Headphone cord seems to be made out of silicon and is a bit longer than what others supply which I appreciated. The organization of the tips with labels is also great. Question: who the heck still uses those airplane 2-plugs as to need this adapter???
1MORE Quad Driver IEM Measurements
As usual, let's start with our frequency response measurement using GRAS 45C fixture:
View attachment 205335
Both channels were similar with plenty of bass which gave me confidence of a good seal. Alas, there is too much upper bass, and not enough treble. I expect the sound to be boomy and closed. So EQ will be mandatory using relative response graph:
View attachment 205336
Distortion was exceptionally low:
View attachment 205337
View attachment 205338
This should give us freedom to do what we want with frequency response. Better yet, once we get rid of the boominess, absolute distortion will shrink further.
Impedance is flat and low at 30 ohm:
View attachment 205339
As IEMs go, this one is a bit more power hungry:
View attachment 205341
Group as with other IEMs, doesn't seem to have much diagnostic value:
View attachment 205342
1MORE Quad Driver Listening Tests
I was listening with my everyday and super neutral Dan Clark Stealth headphone. Switch to 1More immediately caused the boominess to stand out so EQ tools came right out:
View attachment 205343
Most of this should be explanatory except the filter at 8200 Hz. I had to dial this way down as otherwise sound was bright. I am starting to think the target is not quite correction for this region.
At first, I liked the sound but thought maybe someone else would like the stock sound. I listened for 15 minutes and then turned off EQ. Wow, did the sound collapse and became closed, boomy and uninteresting. Don't know where THX got this target response.
The lack of distortion is very obvious as you crank up the volume. There is no hint of distortion as the volume gets dangerously loud! Be careful then with that volume knob as you won't have distortion to cause you to pull back.
There are definitely good things going on here with ultra low distortion allowing us to fix its response. Out of the box, it is bass heavy and trebly shy which means it is not offensive. So can be used without EQ. With EQ, it really comes to life and sounds extremely good. As with most IEMs and headphones though, EQ is mandatory for best sound. Without it, I would not bother with this IEM.
Overall, I can only recommend the 1MORE Quad Driver IEM with EQ.
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/
Here are some thoughts about the EQ.
Notes about the EQ design:
- The average L/R is used to calculate the score.
- The resolution is 12 points per octave interpolated from the raw data (provided by @amirm)
- A Genetic Algorithm is used to optimize the EQ.
- The EQ Score is designed to MAXIMIZE the Score WHILE fitting the Harman target curve (and other constrains) with a fixed complexity.
This will avoid weird results if one only optimizes for the Score.
It will probably flatten the Error regression doing so, the tonal balance should be therefore more neutral.
- The EQs are starting point and may require tuning (certainly at LF and maybe at HF).
- The range around and above 10kHz is usually not EQed unless smooth enough to do so.
- I am using PEQ (PK) as from my experience the definition is more consistent across different DSP/platform implementations than shelves.
- With some HP/amp combo, the boosts and preamp gain (loss of Dynamic range) need to be carefully considered to avoid issues with, amongst other things, too low a Max SPL or damaging your device. You have beed warned.
- Not all units of the same product are made equal. The EQ is based on the measurements of a single unit. YMMV with regards to the very unit you are trying this EQ on.
- I sometimes use variations of the Harman curve for some reasons. See rational here: https://www.audiosciencereview.com/...pro-review-headphone.28244/page-5#post-989169 NOTE: the score then calculated is not comparable to the scores derived from the default Harman target curve if not otherwise noted.
- Occluding IE devices generally must have very good fitting/seal in the user's ear canal for best performance.
please spend a few minutes to pick up the best ear tip... Be sure to perform this step otherwise the FR/Score/EQ presented here are just worthless.
- 1. more bass = better seal
2. More isolation from the outside world = better fit
Great L/R match.
I have generated one EQ, the APO config file is attached.
Score no EQ: 33.5
Score Amirm: 69.6
Score with EQ: 94.0
1MORE Quad Driver In-Ear Full APO EQ [email protected] 96000Hz May092022-142140 Preamp: -12.1 dB Filter 1: ON PK Fc 19.69 Hz Gain 2.30 dB Q 1.16 Filter 2: ON PK Fc 183.76 Hz Gain -5.47 dB Q 0.59 Filter 3: ON PK Fc 738.27 Hz Gain 2.31 dB Q 0.70 Filter 4: ON PK Fc 3069.45 Hz Gain 2.73 dB Q 3.11 Filter 5: ON PK Fc 4257.21 Hz Gain -3.33 dB Q 3.30 Filter 6: ON PK Fc 6747.61 Hz Gain 7.96 dB Q 0.62 Filter 7: ON PK Fc 8442.91 Hz Gain 7.99 dB Q 2.18 Filter 8: ON PK Fc 12523.56 Hz Gain -8.31 dB Q 3.06