[JohnYang1997]

But I will try the behringer ecm8000 since it's pretty cheap and it looks really promising.

 

[hakuzen]

coupler (together with insertion depth) seems to be very important to get closer resonances to reality (so freqs peaks and dips are located more accurately), i think we all agree on that.
but if you are willing to be pretty accurate above 10kHz.. both coupler and mic tolerances are big in this area.
coupler error: Freq range: 20Hz-10000Hz; freq response: ≤±0.5dB(200Hz-5000Hz),≤±1dB(<20Hz-10000Hz) -> you can imagine the error above 10kHz.. it could be >±3dB at 16kHz, for example.
mic error: my "expensive" condenser mic freq range: 20Hz-16kHz; about -3dB at 20kHz. iMM-6, 20Hz-10kHz. cheap electrect, could be like 20Hz-8kHz, for example.
error goes high and manufacturer doesn't guarantee enough stability/consistency outside the range.
you can try to calibrate your mic by using a calibrated high precision mic or by comparing to relative reference measurements, to minimize this error, but i guess a cheap mic will be prone to "loose" this calibration sooner in time and in range than a preciser mic.
i've just received a well calibrated ecm8000 and shall try to calibrate all my mics using it.
but ecm8000 is not ready to be screwed into our couplers, like you have read in @castleofargh post (and impossible to fit in your base/coupler stand). and it is a free field mic (rather than pressure mics, more suitable to be used in our iem couplers). more investigation is required..

 

[JohnYang1997]

coupler (together with insertion depth) seems to be very important to get closer resonances to reality (so freqs peaks and dips are located more accurately), i think we all agree on that.
but if you are willing to be pretty accurate above 10kHz.. both coupler and mic tolerances are big in this area.
coupler error: Freq range: 20Hz-10000Hz; freq response: ≤±0.5dB(200Hz-5000Hz),≤±1dB(<20Hz-10000Hz) -> you can imagine the error above 10kHz.. it could be >±3dB at 16kHz, for example.
mic error: my "expensive" condenser mic freq range: 20Hz-16kHz; about -3dB at 20kHz. iMM-6, 20Hz-10kHz. cheap electrect, could be like 20Hz-8kHz, for example.
error goes high and manufacturer doesn't guarantee enough stability/consistency outside the range.
you can try to calibrate your mic by using a calibrated high precision mic or by comparing to relative reference measurements, to minimize this error, but i guess a cheap mic will be prone to "loose" this calibration sooner in time and in range than a preciser mic.
i've just received a well calibrated ecm8000 and shall try to calibrate all my mics using it.
but ecm8000 is not ready to be screwed into our couplers, like you have read in @castleofargh post (and impossible to fit in your base/coupler stand). and it is a free field mic (rather than pressure mics, more suitable to be used in our iem couplers). more investigation is required..

I am cancelling the order because i dont think it will ever compete with current setup
About the coupler, without my modification, there is huge problem with the resonance frequency. I have two 711s. They both suck between 10k and 20k. But interestingly they work very well on 20k+. So according to my findings, the mic is cheap but good. And you know Chinese lol Chinese. They can get hands on anything. The discrepancy of 711 couplers are huge above 10k. Not only 3db but can be more than 10db between 10k and 16k. The difference is not smooth like mic rolloff but peaks and valleys. That is why I asked to compare those couplers. Thanks for the reply and reading. I love to do measurements, poor me hhha.

 

[JohnYang1997]

[deleted]

 

[hakuzen]

yes, these cheapo chi electret are a true value. you can get a +48V phantom to 9V adapter to use them in your focusrite. got rode vxlr+. or you can diy..

 

[JohnYang1997]

yes, these cheapo chi electret are a true value. you can get a +48V phantom to 9V adapter to use them in your focusrite. got rode vxlr+. or you can diy..

Holy f..s...there is accessory like this? Had rode vxlr but didn't see the vxlr+! Just ordered.

 

[hakuzen]

didn't get such discrepancy between my couplers (above 10kHz) when i tried (check the couplers comparison graph from my post). couldn't compare to the new coupler, because i don't dare to unscrew the fragile mic yet.
can't compare old couplers again because got rid of one, but i'll be able to compare with a new cheap ($13+shipping+fees) "711" coupler i got. but it will take long, many urgent tasks to do before.

 

[JohnYang1997]

didn't get such discrepancy between my couplers (above 10kHz) when i tried (check the couplers comparison graph from my post). couldn't compare to the new coupler, because i don't dare to unscrew the fragile mic yet.
can't compare old couplers again because got rid of one, but i'll be able to compare with a new cheap ($13+shipping+fees) "711" coupler i got. but it will take long, many urgent tasks to do before.

I really wish you to get some thing to compare to ra0045 or 4157/4195. Like the certificate from etymotic. It shows that er4s er4sr er4xr should have a almost flat plane 10k-16k. This is the next best thing to the recommendation stated in itu p.57. You don't need to screw the coupler of AWA or anything, just use the stock mic. I am pretty sure that even AWA won't get it right at 13k, but should be better still. Er6i with resistor is another next best thing to er4's. I have a friend in China has crysound711 and bk4195, but no gras or awa. Crysound being supposedly better than awa can't get it right. But very accurate and low distortion before 10k. I sure need to save up for a second hand ra0045, there are three of them that I know cost 12000 cny/rmb or 1600 usd roughly.

 

[castleofargh]

there is a double issue with the ER4 certificates. the silliest change in insertion depth will throw off the response in the trebles, so we'd need to have a strict reference and be able to stick to it. but then is it the deep insertion expected to be used by the listener? if so what about all the other IEMs that can't go that deep? or is it the standard distance to reference plane? in which case, does it mean anything to have a system aimed to model an average human ear, if we measure the IEMs at the wrong insertion depth?

and the other little point worth mentioning, they calibrate the IEMs by placing them into their rig with a mold of their making instead of using standard tips. the aim is to get rid of some uncertainties potentially caused by how the tip is inserted, but as a result it's not exactly what we do and we do not know if it would really measure the same.

that said I'm very happy to have such a certificate, because better have an approximate reference than no reference at all.

 

[JohnYang1997]

there is a double issue with the ER4 certificates. the silliest change in insertion depth will throw off the response in the trebles, so we'd need to have a strict reference and be able to stick to it. but then is it the deep insertion expected to be used by the listener? if so what about all the other IEMs that can't go that deep? or is it the standard distance to reference plane? in which case, does it mean anything to have a system aimed to model an average human ear, if we measure the IEMs at the wrong insertion depth?

and the other little point worth mentioning, they calibrate the IEMs by placing them into their rig with a mold of their making instead of using standard tips. the aim is to get rid of some uncertainties potentially caused by how the tip is inserted, but as a result it's not exactly what we do and we do not know if it would really measure the same.

that said I'm very happy to have such a certificate, because better have an approximate reference than no reference at all.

The answer to that is. If you have a iec 711 coupler, and setup your er4, then open arta spectrum analyze or fr2 window, you will find a depth that gives a highest 13k. That is the correct place for er4. I insert deeply to the 2nd bend as stated by rin ages ago/so deep that you cant hear your own voice clearly lol. As er4 being one of the rarest non custom earphones that have almost flat response 10k -16k. And the reference plane is where the coupler measured in development suggested in itut p.57. Making this imo the best way to evaluate a simulator on our own.
For regular shallow insertion earphones, as they are already far away from reference plane, the biggest difference should be around 8-10k. Because the resonance frequency shifts lower as the volume/length increased. Frequency over 10k should be pretty stable for this type. But many shallow insertion earphones don't have linear fr over 10, the measurements are much less meaningful.
How deep should you insert your earphones? As the coupler is to simulate the human ears, the depth should be the same as the earphones designed for. But not saying that you can't measured it at reference, it is just won't reflect the hearing. However, for some earphones like e3000 ,heaven v, f7200, x11, you can possibly insert deeply into your ear canal. It is perfectly fine to measure them at reference plane as well as shallow . But this is considered as modification even tho you don't really change anything on the earphone itself, to me it is one of the most useful modification to a pair of earphones.
Ciem wise, there are ways to measure the earphones with deep insertion. I think bartzky knows a bit more on this as I only had one ciem and I sold it in 2015.

 

[JohnYang1997]

For shallow insertion earphones, we don't even get a consistent sound when listening to them. They tend to slip out overtime right? That is why I love etymotic that much.
For measurement consistency reason, you may insert the earphones at such depth the housing is against the ear canal/external simulator. Or as Sead from sony stated at the small circular mark on the eartip.

 

[castleofargh]

yup I was talking about sticking to standards. my own use is 99% for my EQ, so of course I try to match the insertion and resonance frequencies to what I'm getting in my ears. and I accept that this is no standard measurement. having insertion difficulties with some models really make the IMM6 and a silicone tube great. it's easy to measure the distance, with the transparency. it's easy to adapt to any special need. while it's not standard to anything, it's really convenient. ^_^

 

[JohnYang1997]

yup I was talking about sticking to standards. my own use is 99% for my EQ, so of course I try to match the insertion and resonance frequencies to what I'm getting in my ears. and I accept that this is no standard measurement. having insertion difficulties with some models really make the IMM6 and a silicone tube great. it's easy to measure the distance, with the transparency. it's easy to adapt to any special need. while it's not standard to anything, it's really convenient. ^_^

Stick to your hearing, will be better if you can demo some high end near-mid field speakers like event opal and adjust eq yourself.

 

[Glebuzzz]

Any plans on measuring updated Westone's UM Pro line up? I guess differences between new and old models would be non-existent but still.

 

[goodvibes]

I'm wondering if Adel and Apex models don't play as well with the rig and may need alternate compensation in the bass. While linear mic response is just that, once your in pressure wave response, perhaps the mic has more resistance to movement than an eardrum causing more pressure to to be diverted to adel/apex than in another fully sealed inear. Very little difference could become noticeable and the Adel/Apex models consistently show less bass quantity and more low bass roll compared to review descriptions.