BLON BL-03 MOD MEASUREMENTS
Alright so I spent my 2 days measuring the BL-03 with some mods, hopefully these are useful.
In case you don't know, THe BLON BL-03 also using infamous nylon cloth mesh as a damper underneath the metal nozzle grill. Im into simple modding IEM, not into extreme mod or anything else, but from my experience, this kind of damper have more bad effects rather than its goodness.
The nylon cloth mesh dampers are believed by chifi manufacturer to smoothen upper mids region, while that doing good for the purposes, they also came with bad effect altogether, the main issue is bad airflow especially with IEM containing DD. THis will make bass part become bloated, think of covering vents with something, bass become bigger in quantity but sounded bloated. Other bad issues are reduced clarity, and blurry imaging (reducing imaging quality).
Moondrop lately found a way using similar cloth damper but I have yet to know what material they are using (mine still on the way) that sold separately. THeir damper although using similar cloth, may have different effect. Why? because they made a gap between the the damper and the grill. This is a clever way to avoid air flow blockage, but I need to listen myself if they still make bass bloated.
So some of us tried to remove / change the grill to make the IEM sounded better, but sometimes the default tuning without damper are too peaky, so we have to damper them with different way that better than using nylon cloth mesh.
THank you to
@Slater that found this BL-03 are using that infamous cloth mesh damper, I didn't think at all that they are using the cloth mesh damper, you can take a look of his great tutorial few pages back (someone help me find the link, i will post here for easier findout)
So I tried to mod with several materials to find which are the best, I mod and measure every materials that i use hopefully this will be useful for the community.
OK, to begin with, here is my rig, using similar rig with
@crinacle because I feel his measurement is one of the best in the world, and I used to see his graph among others. I'm using IEC711 coupler copy, with apple dongle, with REW, calibrated to have similar result with crinacle and always try to keep resonance peak as close as 8khz. Crinacle is using wide bore for measurement, but I'm using medium bore that can fit lot of my IEM, and more important stay inside the coupler with proper seal. So slight differences can be caused of eartips being used, unit variance on IEM themselves, unit variance on dongle, unit variance on coupler, mic, cables etc.
Comparison between My graph and
@crinacle 's. His graph as always credits to him with respect.
Here the default BL-03 FR by Crin :
And here my measurement on BL-03 default :
As you can see, my L (green lines) unit have lower bass quantity, i checked everything, holes, vents, tried different cables etc with no dice. I take that as driver unit variance. Too bad i just give my second BL-03 to my relatives earlier this year.
So i will use the R unit as reference since my L unit seems off with that roll off bass (but hey that is tuned better actually i guess?)
This is measurement to compare between default BL-03 with cloth mesh filter and filterless. Brown is default, Blue is filterless
To my ears, the bass is a lot cleaner due gone of bloated effect caused by that cloth mesh. On graph they cant be really seen, but its very obvious to my ears. same with bass decat, texture that you can't see from an FR graph.
Right, so the filterless BL-03 have peaky +13db pinna gain on roughly 2.2khz, 5.5khz and 8khz. Scariest peak is on that 5.5khz, that shouty sibilances. We did try several method to tame down that peaks so I try to measure a lot of materials for our curiosity.
Dried alcohol swab (red line) rolled on side of nozzle with no blockage at all on center of nozzle tamed the peaks a little bit, the bass still very clean, fast, tight, like filterless which is great result, but the peaks may a bit shouty to some.
Rolled cotton (green line on FR), roughly square 7mm put into nozzle, similar to alcohol swab, more like a "C" in the nozzle rather than full circle donut, because its easier. The result tame the peaks as much as the original filter, but of course with no bloated bass, but the cotton absorb too much upper mids and trebles, extension of the cymbals, decay of snares sounded gone too fast, very minimum resonance.
Next up is Soft foam (bright red line) , its a foam with very soft density, like almost no power to bounce back if you pinch it. I got them from the hard case for IEM. I cut rounghly 5mm in length, with width and depth lower than nozzle diameter, so they still have plenty space of air. Result is pretty good, Bass is tight, no bloat with litlle bit smoother upper mids but without losing of clarity and treble extension. Can be a little shouty, just occasionally happen, but i like a little bit tamed upper mids, at least below 10db increment from 1khz.
With longer soft foam (roughly 10mm) (tosca line) the upper mids is tamed down, very smooth result, similar to original state but better bass (no bloated), 8khz treble resonance peak also tamed down. I like this tonality but maybe i want to cut down the soft foam a little bit more for more aggressive and fun signature, just slightly.
left green foam : animal sponge (capsule animal sponge in 1 dollar store), soft density but not as soft as right one
right black foam : soft foam from IEM case, very soft density with a lot of cavities)
This time, I was using animal sponge (purple line). What the heck is that? that is a sponge that i found quite good that i use in the past for mod, they can be bought on one dollar store, a capsule sponge animal, put into the hot water and the sponge animal will popped out
something like this, image by google.
Result is very good too, with smooth upper mids but still non bloated bass, but the softer density foam (the black one above) do better job on clarity, remember to cut smaller than nozzle diameter so they can be fit without any force, dont put big cut and pinch to insert, they will be too full and muffled the sound.
Alright so next one is our popular mod tool, the 3M micropore, with full cover, covering the entire nozzle (peach line). As you can see and inline with what im hearing, they produce similar result with default BL-03 with that cloth mesh filter, bloated bass, you can see the bass FR there, back to original state, what you can't see is how bad the bloat, the texture. Upper mids also sounded a little bit veiled.
Next is I pinched a hole on that micropore tape, just 1 hole in the center (magenta line), bass is better than full micropore covering entire nozzle, but still have smear, not as clean as other mod.
Then i went crazy, stabbing the micropore on nozzle so they have many holes lol (on purpose) (showed in dark green line), bass become great, non bloated, much better than full micropore or micropore with 1 hole, logically of course make in common sense, better airflow for the DD. The upper mids of course less tamed than full micropore or just 1 hole, as you can see, but this is pretty good result too.
Then I ditch that micropore, changed into new micropore but now I cover only 3/4 of nozzle hole (dark red line), left with roughly 1/4 open, unfiltered. This is a classic mod and now proven this is a very good solution too, and very easy way too for beginner. Bass is clean, non bloated, very nice clean bass like the unfiltered one, the upper mids is similar with micropore with many holes. Great result too!
Just to kill curiosity, i reduce the micropore into half, covering only half of nozzle opening (green line). Bass of course great like filterless, but the upper mids also similar like filterless, too shouty. Hence, I didn't bother to try with 1/4 cover nozzle with micropore.
So out of few experiments with different materials, I like the 3/4 micropore cover and soft foam as the best result among all. As a note, sony is using soft foam as a damper, its no joke, they put soft density foam on the nozzle without any grill, but keep in mind that they did their homework, they tuned the Z1R for example with crazy bosst high mids but then put the foam, or the other way, they tune and measure with foam attached.
Conclusion, chifi manufacturer need to stop put this nylon cloth mesh glued together with grill as damper. They will bloat the bass. My H40 have similar effects too, and with the mod, the H40 is crazy, much better result than the BL-03 mod.
I'm sorry for super duper long post, but i feel its necessary to post everything in 1 post. Thanks for reading, sorry for your bandwidth.