This is a follow up of my previous impressions of PM4 I posted here:
http://www.head-fi.org/t/796729/trinity-phantom-series-new-thread-worlds-first-push-pull-hybrid-iem/9240#post_13062483
Since last week I've 3 units of PM4 to test. I ordered 2 Gunmetal and received 1 Black and 1 Gunmetal. My friend ordered a PM4 and use my address for delivery. He ordered a Gunmetal, but delivered Black. So no I have 2 Blacks and 1 Gunmetal for testing. First Black came with extra whirlwind generic ear tips. The Gunmetal came with extra SpinFit ear tips. The 2nd Black unit didn't come with extra ear tips. So there is inconsistency here.
From all three, so far I don't see any issue with build quality. Only one piece of Gold filter that can be screwed to the Gunmetal PM4, but cannot be well tightened. The rest are good so far. I haven't tested all the 3 sets of filters from all the 3 PM4, but so far haven't seen any major issue with the build quality.
For me, comfort and fit are good. No issue with fitting so far and PM4 feels very comfortable even for a very long period of use.
After having more time with PM4 with my preferred filter, Gold Damped, I would say that I'm started to be able to accept and even enjoy the sound signature of PM4. There are some fuzziness or a kind of muffledness around the midrange area, it is still there, but sounds less with Gold filter and only become a problem with very complex orchestral music, and not so much of a problem, or I can say ignorable with simple Pop songs and other less complex arrangement. Generally, PM4 doesn't perform very well with fast and busy music, but more towards smooth pleasing sounding type of sound signature.
The fuzziness in the midrange varies between the Black PM4 and the Gunmetal PM4. The difference is not night and day but quite noticeable. Both Black PM4 have a similar level of fuzziness, while the Gunmetal PM4 sounds noticeably cleaner with better clarity. The differences between the Black units and the Gunmetal unit is not really clear from the measurement, but I can confirm that the Gunmetal PM4 sounds noticeably cleaner with better instrument separation than the 2 Black units. With the Gold filters (damped and undamped) the fuzziness I perceived as minimal and still acceptable. But previously with the gunmetal filter, the level of fuzziness was rather annoying for me. I find the Purple and Silver sound filter give either not enough bass or too much bass, therefore I didn't spend much time with Purple and Silver sound filter.
I tested all the 3 PM4s with the same pair of sound filters for better consistency. So I remove the filter and screw into the next PM4 for testing. As for the gears, I tested the PM4 using Onkyo DP-X1, Fiio X3ii, LH Geek Out 450, and ifi micro iDSD. My subjective opinion for which source sounds best with PM4 is as the following, from best (top) to less preferred (bottom):
ifi micro iDSD
LH Geek Out 450
Onkyo DP-X1 & Fiio X3ii
I did measure all the 3x PM4s using my standard equipment which is MiniDSP UMIK-1 measurement microphone and DIY acoustic coupler that I made using 5 layers of heat shrink tubing. I did some experiments with the acoustic coupler, with different length of the acoustic couplers, and use the one that I observe to show the closest result to what I perceived by my ears, and also comparing to FR measurements from manufacturers.
I measured every channel twice with unplugging and refit the IEM into the acoustic coupler. So after a measurement, I unplug the IEM from the acoustic coupler, fit it back, and measure. I did this to check the consistency of the measurement. I actually did more than twice for some of the units, and so far the measurement results have been quite consistent. At last, I measured my reference IEM for tonality flatness, the DUNU DN-2000, also to check the consistency of the measurement setup. I use Fiio X3ii as USB DAC, and Room EQ Wizard program.
Here are the screenshots of the 3 units of PM4: Black1 and Gunmetal that belong to me, and Black2 unit that belongs to my friend. Also included the DUNU DN-2000 measurement done in the same session. All measurements are using gunmetal sound filter with the stock foam ear tip. I only use 1 gunmetal filter with 1 foam ear tip for all the drivers. So I unscrew from the previous driver and screw the filter to the next driver. This is to maintain the consistency of the measurement. I use foam ear tip for better alignment to the axis of the measurement microphone. Foam ear tip holds the driver better than the silicone ear tip and showing better consistency between measurements. The measurement showing frequency response and distortion analysis. I would say after measuring all 6 drivers (3 Left and 3 Right), the consistency between drivers is pretty good. I've seen much worse from higher priced IEMs.
PLEASE TAKE NOTE:
The measurement equipment I used here is not a standard measurement equipment to measure IEM, therefore I cannot guarantee that the results below are accurate. The reason for showing the measurement result is only to show COMPARISONS between 3 different PM4 units and my reference IEM DUNU DN-2000. Please DO NOT use the following measurement results to be compared with other measurement results.
PM4 - Black1
PM4 - Gunmetal
PM4 - Black2
DUNU DN-2000
FR of all 3x PM4s and DUNU DN-2000
For those who would like to analyze the REW measurement result, you can download it here.
MiniDSP UMIK-1 and the DIY acoustic coupler:
http://www.head-fi.org/t/796729/trinity-phantom-series-new-thread-worlds-first-push-pull-hybrid-iem/9240#post_13062483
Since last week I've 3 units of PM4 to test. I ordered 2 Gunmetal and received 1 Black and 1 Gunmetal. My friend ordered a PM4 and use my address for delivery. He ordered a Gunmetal, but delivered Black. So no I have 2 Blacks and 1 Gunmetal for testing. First Black came with extra whirlwind generic ear tips. The Gunmetal came with extra SpinFit ear tips. The 2nd Black unit didn't come with extra ear tips. So there is inconsistency here.
From all three, so far I don't see any issue with build quality. Only one piece of Gold filter that can be screwed to the Gunmetal PM4, but cannot be well tightened. The rest are good so far. I haven't tested all the 3 sets of filters from all the 3 PM4, but so far haven't seen any major issue with the build quality.
For me, comfort and fit are good. No issue with fitting so far and PM4 feels very comfortable even for a very long period of use.
After having more time with PM4 with my preferred filter, Gold Damped, I would say that I'm started to be able to accept and even enjoy the sound signature of PM4. There are some fuzziness or a kind of muffledness around the midrange area, it is still there, but sounds less with Gold filter and only become a problem with very complex orchestral music, and not so much of a problem, or I can say ignorable with simple Pop songs and other less complex arrangement. Generally, PM4 doesn't perform very well with fast and busy music, but more towards smooth pleasing sounding type of sound signature.
The fuzziness in the midrange varies between the Black PM4 and the Gunmetal PM4. The difference is not night and day but quite noticeable. Both Black PM4 have a similar level of fuzziness, while the Gunmetal PM4 sounds noticeably cleaner with better clarity. The differences between the Black units and the Gunmetal unit is not really clear from the measurement, but I can confirm that the Gunmetal PM4 sounds noticeably cleaner with better instrument separation than the 2 Black units. With the Gold filters (damped and undamped) the fuzziness I perceived as minimal and still acceptable. But previously with the gunmetal filter, the level of fuzziness was rather annoying for me. I find the Purple and Silver sound filter give either not enough bass or too much bass, therefore I didn't spend much time with Purple and Silver sound filter.
I tested all the 3 PM4s with the same pair of sound filters for better consistency. So I remove the filter and screw into the next PM4 for testing. As for the gears, I tested the PM4 using Onkyo DP-X1, Fiio X3ii, LH Geek Out 450, and ifi micro iDSD. My subjective opinion for which source sounds best with PM4 is as the following, from best (top) to less preferred (bottom):
ifi micro iDSD
LH Geek Out 450
Onkyo DP-X1 & Fiio X3ii
I did measure all the 3x PM4s using my standard equipment which is MiniDSP UMIK-1 measurement microphone and DIY acoustic coupler that I made using 5 layers of heat shrink tubing. I did some experiments with the acoustic coupler, with different length of the acoustic couplers, and use the one that I observe to show the closest result to what I perceived by my ears, and also comparing to FR measurements from manufacturers.
I measured every channel twice with unplugging and refit the IEM into the acoustic coupler. So after a measurement, I unplug the IEM from the acoustic coupler, fit it back, and measure. I did this to check the consistency of the measurement. I actually did more than twice for some of the units, and so far the measurement results have been quite consistent. At last, I measured my reference IEM for tonality flatness, the DUNU DN-2000, also to check the consistency of the measurement setup. I use Fiio X3ii as USB DAC, and Room EQ Wizard program.
Here are the screenshots of the 3 units of PM4: Black1 and Gunmetal that belong to me, and Black2 unit that belongs to my friend. Also included the DUNU DN-2000 measurement done in the same session. All measurements are using gunmetal sound filter with the stock foam ear tip. I only use 1 gunmetal filter with 1 foam ear tip for all the drivers. So I unscrew from the previous driver and screw the filter to the next driver. This is to maintain the consistency of the measurement. I use foam ear tip for better alignment to the axis of the measurement microphone. Foam ear tip holds the driver better than the silicone ear tip and showing better consistency between measurements. The measurement showing frequency response and distortion analysis. I would say after measuring all 6 drivers (3 Left and 3 Right), the consistency between drivers is pretty good. I've seen much worse from higher priced IEMs.
PLEASE TAKE NOTE:
The measurement equipment I used here is not a standard measurement equipment to measure IEM, therefore I cannot guarantee that the results below are accurate. The reason for showing the measurement result is only to show COMPARISONS between 3 different PM4 units and my reference IEM DUNU DN-2000. Please DO NOT use the following measurement results to be compared with other measurement results.
PM4 - Black1
PM4 - Gunmetal
PM4 - Black2
DUNU DN-2000
FR of all 3x PM4s and DUNU DN-2000
For those who would like to analyze the REW measurement result, you can download it here.
MiniDSP UMIK-1 and the DIY acoustic coupler:
