[hakuzen]

sort of global response: we have to determine what we're trying to achieve. best measurements or sort of realistic measurement? because holding the IEM in place is something that doesn't necessarily happens in our ears even when the shell is securely fit on part of the pinna and ear canal, all that stuff is flexible.
same for the idea of not using tips. for anybody who needs to make repeated measurements that must achieve the same response, obviously getting rid of the tips is the best approach. Etymotic has a sort of mold where they insert the IEM without tips to measure and match the pairs of the er4 series, and probably to test a lot of stuff on the other models. but the reliable, highly repeatable response we get is not what an actual ear will get. and that to me is a problem. I'm well aware that even the IEC standards are in the end practical choices, some even suspiciously arbitrary IMO, but at least those are references that most people have learned to interpret subjectively(with more or less accuracy). I personally feel that there is value in all those years of habits. if a new better standard comes along and is accessible to us amateur nerds, I'm up for it, but it needs to be something accepted by most people, or we need to have such a massive output of measurements that we can become our own reference, like Tyll did with innerfidelity, like crinacle is doing right now. we accept that their measurements might not mean much in term of standard, but they provide big enough samples of measurements for us to get the relevant relative variations compared to some IEM we have used ourselves.

@hakuzen the most successful changes for me in term of vibration:
- delay the measurement by 2 or 3 seconds in REW, click and move away. or put the mouse on a different desk and stay away ^_^
- measure from 10 or 15Hz instead of 20Hz. I still only look at and show from 20 to 20K, but sometimes it avoids some wiggly artifacts in the subs. no idea if that's due to my gears or if it's something that sometimes happens in REW? same thing with measuring impedance, on rare occasion the impedance curve takes a dive in the upper range, and if I do it again, it rises(if BA), or does whatever it's supposed to measure. I don't seem to be changing anything, so I assume it could be REW. I remember seeing Purrin show such an impedance response that wasn't right in the treble, so I assume it might happen to others too. for that beyond doing several measurements, I'm not sure how to avoid it from happening(but it's super rare for me anyway).
- using a fanless computer. I only do it when I'm really looking for something super specific, because the fanless one I have was crap when it was new, and that was years ago^_^. it's just so slow I go mad from using it. so I usually measure with my rather noisy but responsive one as for FR at least, it's irrelevant so long as I measure a signal in the 80-90dB SPL. but for distortions, in my case it changes everything. I've done stuff to reduce the noise coming from my regular computer too, with yoga brick, acoustic panels, pillows, etc, but none of that can stop low frequencies. so to my ears it's pretty quiet, but my mics disagree ^_^.
- electrical pollution. some gears are just more sensitive than others, but it seems pretty common to have some little 50 or 60Hz noise, or other stuff when some equipment is running in the house. my personal nemesis is my fridge. if it starts running while I measure stuff, noise and distortion levels increase instantly.
- in the dead of the night is always where I got my cleanest measurements, because people sleep. even from an electrical point of view things are just better for me usually after 1AM. again, that doesn't matter for FR, only for stuff measured some 40dB below signal and lower.
- try to feed the mic with different sources. when I started this, I was always feeding my Vibro Veritas with a really noisy and crappy soundcard from my laptop, and it's only when I got other mics requiring different sources/plugs, that I realized how crappy the laptop's DC powering the mics really was. I made an adapter to still be able to use most stuff from the laptop, and that was my wake up call. virtually anything was cleaner, my tablet, phone, some batteries, they all were a lot cleaner. now I mostly use a mic that requires 48V of phantom power, so I don't really have a choice. but for the dayton it might be worth trying a few devices just in case.

well I guess we could also just have proper gears and clean quiet room, but I at least will never have that.

thanks for the heads up!
last version of REW uses a new way to show noise before and while measuring, more graphical. now you can see clearly the impact of mouse clicking, pc fan, your movement, neighbors or street noise, etc.
i already use a 3 seconds delay, and even hold my breath while measuring, lol.
do measure from 0 to 96kHz as a rule (think is better for impulse response calculations, and don't want to redo measurements to check behavior till 48kHz; all gear calibrated for that resolution, of course).
for impedance measuring, found that is mandatory calibrating impedance before measuring, always you try a new iem.
the fans from my pc are quality low noise fans (!beQuiet), but still noisy when they activate while measuring. purchased a mini pc at 3.28 for multimedia (including measuring audio) purposes, although it has a 8cm fan. and i've not mounted yet an ultra silence desktop pc (big fans, acoustic isolation panels), which will be on the floor rather than on the desk. so i hope to get a big improvement soon.
trying to measure at night. during the day, buses, traffic, neighbors, and two schools just in front of my home, create excessive noise and vibrations.
my measuring mic also gets feed with 48V phantom power, from creative EMU-0404, which features ground lift and it's fed by a quality low noise usb feeder through isolated canare cable + quality plug. amplifier used is JDSLabs C5D, low noise, distortion, and impedance, fed by internal battery when measuring. i have to locate sources of electrical pollution. already have to mount an EMI filter i purchased to reduce high frequencies noise and stabilize the AC (i have to add some plugs and make the connections, including modification of the power strip current take), to feed all gear (pc, usb feeder, etc.).
another good way to decrease noise while measuring, is using 2 sweeps of 2M in REW. slower, and ram consuming, but it works very well for definitive measurements.

my recent main problem is the noise and lows distortion created by the press touching the iem. i wouldn't mind if the tips slide off a bit and stay in the coupler, but they get out completely, so using the press is mandatory for those tips, although it barely touch the iem, making minimum pressure (it's just a top limit).
i've added soborthane feet to the press, and replaced the end rubber which touch the iem with a smaller one, naked (no putty nor soborthane), a few hours ago; the improvement has been great.
but the difference is still noticeable: from -80 to -60dbFS when not using the press, to -50 to -40dBFS. from zero extra lows distortion, to some extra distortion below 40Hz (0.5% to 1.5% = 10dB, in flc8s).
i'm satisfied with last improvement. to generate distortion curve, i'll use the self-staying tip which measures nearer to stock or reference tip. for frequency response, these new numbers allow a smooth raw curve when using the press.

 

[CoiL]

I just measure at night and hope not to fart

 

[guicnovaes]

Has anyone here measured the HiFi Boy OS V3?

Thanks in Advance.

 

[CoiL]

So, my question to iMM-6 users would be - which is the correct length from mic to tip edge when measuring and also correct diameter of tube?
Please make this clear for everybody for better consistent measurements @ iMM-6.

Any consensus on this?
I want to be sure before I start measuring other IEMs I have and can get hold on for measuring.

 

[castleofargh]

Any consensus on this?
I want to be sure before I start measuring other IEMs I have and can get hold on for measuring.

no sure there is one. clearly a basic tube is not the modern standard for anatomically correct coupler, so trying to come close to some IEC standard anyway is more of a personal desire than a necessity IMO. even for those of us who have a 711 knock off, this standard is old and new ones have come since.
my simple answer would be align with whoever you're trying to imitate. but human ears are different in length, I think on average females have it like 3 or 4mm shorter, and that's on average. the actual variations on a population are a good deal bigger. then you add to that how many IEMs are simply not made to be inserted the same way, or how some use part of the shell as an extra cavity changing the overall resonance game, and you have to come to the conclusion that we're all trying to get the best result so that some dummy head can have a personal connection to our measurements ^_^. but how relevant are those for us actual listeners? that will depend. personally, when I measure stuff for myself I insert less than I would for fake official graphs, because I have a big head with big ear canals and to my ears, this is more accurate. but as my size isn't average anything, I don't assume that those result will be correct for most people. different objectives lead to different methods. so imitate someone, or simply publish enough following your protocol so that you are your own reference(which IMO is always the best option when available).

 

[kadas152]

Any consensus on this?
I want to be sure before I start measuring other IEMs I have and can get hold on for measuring.

It would be really awesome to have consensus on this at least some unofficial guidelines for iMM-6 users here to make measurements at least similar.

I’ve originally created my tube to imitate crin’s results thus that 8k resonance peak in my measurements. But I am definitely open to another standard here as quite a few of you doesn’t seem to agree with that.

 

[CoiL]

Considering my ears and ear-canals are small and current measurements align to what I hear - I think I will stay with measuring distance ~13mm.

Maybe we (iMM-6 users in this particular thread) could set different measuring lengths for S / M / L size ears (according to tips size used) ?

My suggestion would be:
~13mm for S-size tips/small ears
~17mm for M-size tips/medium ears
~21mm for L-size tips/large ears

Open for discussion/suggestions for other distances.

Or does it sound absurd/pointless?

 

[hakuzen]

i like crin solution (as valid as any other one, like @castleofargh explains, while you are consistent): try a measurement, and change insertion depth until you get 8kHz peak resonance well located.
then, if you are using a tube, and insertion was too deep, get your tube shorten, to allow more comfortable insertion

 

[CoiL]

try a measurement, and change insertion depth until you get 8kHz peak resonance well located.

What do You mean about it exactly? Locate that peak for Your hearing or adjust that peak for 8kHz (like crin does)?
If latter, then I will question WHY when in reality I do not hear peak at 8kHz?

 

[kadas152]

i like crin solution (as valid as any other one, like @castleofargh explains, while you are consistent): try a measurement, and change insertion depth until you get 8kHz peak resonance well located.
then, if you are using a tube, and insertion was too deep, get your tube shorten, to allow more comfortable insertion

That’s exactly what I am doing.

 

[CoiL]

Ok, as I understand we are having two opposing sides:

1) adjusts/calibrates mic to 8kHz peak/resonance
2) adjusts/calibrates mic according to their hearing and other measurements of same IEM

I personally prefer second and probably will measure like that, cuz if person knows his/her hearing sensitive areas, he/her would like to know/read out those areas from graph.
For example, if I look at crins 8kHz peak @ IT01 and would like to buy it potentially, I would ditch the plan because I`m really sensitive to 6.2-7.5-8kHz frequencies.
But in real world I do not hear such 8kHz as graph suggests.

 

[castleofargh]

Ok, as I understand we are having two opposing sides:

1) adjusts/calibrates mic to 8kHz peak/resonance
2) adjusts/calibrates mic according to their hearing and other measurements of same IEM

I personally prefer second and probably will measure like that, cuz if person knows his/her hearing sensitive areas, he/her would like to know/read out those areas from graph.
For example, if I look at crins 8kHz peak @ IT01 and would like to buy it potentially, I would ditch the plan because I`m really sensitive to 6.2-7.5-8kHz frequencies.
But in real world I do not hear such 8kHz as graph suggests.

again it's a matter of what you're trying to achieve. at some point I considered how other members would benefit from a given way of measuring, but TBH, those who have a fair understanding of measurements will always be wary of comparing graphs made by 2 different sources, while everybody else is going to assume that all graphs are comparable and often don't even bother reading if a compensation is applied.
the power of crinacle's method is not about being right or super technical, his force comes from the sheer scale of his database. he effectively made himself a reference by offering measurements of so many IEMs. so in that respect, there is meaning to copying him a little because people are bound to use your graphs and compare them to his at one point or another. the same way innerfidelity was the reference for headphone measurements. Tyll measurements had a number of issues/personal choices, but the number of headphones measured that way made it a point of reference for all the headphone community and perhaps even for some of the pros when they had to start from nothing.
I don't publish much so it makes more sense for me to care about my number one follower, me ^_^.
you could also decide that comparing graphs from different sources is objectionable(and TBH you'd be right), and decide to go your own way as a clear warning that your graphs should only be compared to your own other graphs.

I don't believe that there is a wrong choice here. personally I would never put a measurement of an IEM at some reference plane if typical insertion is obviously different. but that has obvious consequences, most of which go against repeatability. we all end up wondering about those stuff(usually while doing measurements), and we rarely all agree on what is "the right way". standards are cool because they offer increased stability, but do they make a graph look more like what people are hearing? I'm not convinced.

 

[hakuzen]

What do You mean about it exactly? Locate that peak for Your hearing or adjust that peak for 8kHz (like crin does)?
If latter, then I will question WHY when in reality I do not hear peak at 8kHz?

i mean, do a FR measurement of your iem with your actual tube and insertion depth. check where the ~8kHz is located in your graph; depending of distance (tube length+insertion depth), it could be located from 7kHz to 9kHz (for example). change insertion depth and measure again (you'll see how the peak "moves" depending of insertion), until the peak is centered at 8kHz.

the 8kHz peak can be louder in some iems compared to others, but that resonance is always there. you say you are sensitive to 6.2-7.5-8kHz freqs. if the peak is loud, you'll notice sibilance surely; when the peak is more moderated, it's less noticeable.. but it is there.
also, some tips tame the amplitude of that peak (foams and long tips), and insertion depth can do it as well.. but the peak is there..

 

[CoiL]

Ok. Thanks guys. Will think about everything and try that 8kHz peak-alignment too. Meanwhile I have taken down my measurements as I think I need to calibrate it WAY more seriously regarding different frequencies dB level difference.
I`m not planning to provide measurements of many chi-fi IEMs, only those I have and like, plus some modded IEM differences.

 

[csglinux]

Like I said earlier, I think shooting for an 8 kHz resonance peak is a really bad idea. If you create graphs this way, you could make two dissimilar IEMs look to have similar treble performance. That's just misleading.

And what are you going to do with the Zero Audio Carbo Tenores? Which peak are you going to move to 8 kHz??

This would only makes sense if you carefully adjust the insertion depth (with extra-length eartips) for each and every IEM you listen to, in order to make sure you always hear a peak at 8 kHz. And if you do that, you're nuts. IMHO.