[JohnYang1997]

I ordered ecm8000 this morning, lets see what i can do with it.

 

[castleofargh]

I ordered ecm8000 this morning, lets see what i can do with it.

a warning though. to be able to fit it inside the coupler, I had to remove the coupler's internal thread that you normally use to screw the proper mics in place. so unless you can tear down the coupler and replace that piece with another identical but threadless piece, it's a definitive modification.

and I also had to deal with all the little vertical extrusions on the head of the EMC8000 because while they seem very nice in free air measurements, they were clearly messing too much with the upper range.

so I'm not sure it won't take you ever further away from your objective of having more reliable trebles(based on whatever standard of an ear).

aside from that, I'm fairly happy with the noise floor I get(noise in my room is typically picked before the mic or my ADC). as for distortions, this is a wild guess because I don't have great gear to compare with, but I seem to get a trend where the EMC8000 should be tested at something like 80 or 85dB max, instead of what I'm used to do, setting up 1khz at 90dB SPL and getting close to 100dB at 3khz on many IEMs. it's a game of keeping the mic's own distortions low, and still staying far enough from ambient noise.




unrelated, I got a solution from MiniDSP for the EARS and my +24dB mic boost locked in the settings. it was a test thing and it got initialized with a fast little game of moving the jumpers a certain way and unplugging/plugging. so all is well and I have a working setup to play with.

 

[JohnYang1997]

a warning though. to be able to fit it inside the coupler, I had to remove the coupler's internal thread that you normally use to screw the proper mics in place. so unless you can tear down the coupler and replace that piece with another identical but threadless piece, it's a definitive modification.

and I also had to deal with all the little vertical extrusions on the head of the EMC8000 because while they seem very nice in free air measurements, they were clearly messing too much with the upper range.

so I'm not sure it won't take you ever further away from your objective of having more reliable trebles(based on whatever standard of an ear).

aside from that, I'm fairly happy with the noise floor I get(noise in my room is typically picked before the mic or my ADC). as for distortions, this is a wild guess because I don't have great gear to compare with, but I seem to get a trend where the EMC8000 should be tested at something like 80 or 85dB max, instead of what I'm used to do, setting up 1khz at 90dB SPL and getting close to 100dB at 3khz on many IEMs. it's a game of keeping the mic's own distortions low, and still staying far enough from ambient noise.




unrelated, I got a solution from MiniDSP for the EARS and my +24dB mic boost locked in the settings. it was a test thing and it got initialized with a fast little game of moving the jumpers a certain way and unplugging/plugging. so all is well and I have a working setup to play with.

I cancelled the order because it's not going to surpass the current setup with my modification.

 

[castleofargh]

probably not, that's why I thought I should post this warning. given our small conversation and a few of your posts, it is clear that you aspire for more of a reference curve than I do. I basically am happy so long as I can get variations between 2 measurements with reasonable accuracy, and usually disregard the results above 10Khz. they only serve me to confirm that I inserted an IEM at the same distance again.

 

[JohnYang1997]

probably not, that's why I thought I should post this warning. given our small conversation and a few of your posts, it is clear that you aspire for more of a reference curve than I do. I basically am happy so long as I can get variations between 2 measurements with reasonable accuracy, and usually disregard the results above 10Khz. they only serve me to confirm that I inserted an IEM at the same distance again.

Did you see my modification post? That was insane.

 

[JohnYang1997]

Reply to OP, rin's 711 is from BSWA.
Quote: ' Last time I got a quote from BSWA USA in April 2011, the price of this simulator was $3150 each.'
http://rinchoi.blogspot.com.au/2012/08/introducing-my-60318-4-occluded-ear.html

 

[castleofargh]

Did you see my modification post? That was insane.

on crinacle's topic yes. I had only missed the pic of the coupler from below that looks like you removed a ring in it. I took mine apart for the lolz, and to get rid of the thread, but I didn't try to measure anything without some parts. I suppose it could be fun to do some day.

 

[JohnYang1997]

on crinacle's topic yes. I had only missed the pic of the coupler from below that looks like you removed a ring in it. I took mine apart for the lolz, and to get rid of the thread, but I didn't try to measure anything without some parts. I suppose it could be fun to do some day.

That's very nice. I didn't remove a ring but i did try to tho. But I failed :.(

 

[csglinux]

got a little free time this morning so I went on with it. here are my cheap amateur measurement rigs in a few examples (not enough to really get a pattern, just enough to make a mess ^_^).
gear used:
-output: Odac/O2
- IEMs: ER4SR(sealed deep insertion), XBA_C10(sealed, can't go deep), Fiio EX1 AKA rebranded Titan1(super mega vented and dynamic driver).
-inputs: that's where it gets fun.
option 1@@@@: MiniDSP EARS (USB)

option 2@@@@: IMM6 made to use on cellphones and tablets.

I fed mine with a cellphone for the DC voltage, but recorded into a Scarlett 2i2.TBH as far as FR is concerned, I get almost the same results with a cheap 30$ Startech USB ADC, or even with my laptop's mic input.
a silicone tube is added to be able to measure IEMs with a seal while at a more appropriate distance(see the hundred measurements done by @crinacle using this little cheap mic).


option 3 @@@@: EMC8000 stuck into a fake IEC711 coupler, massively DIY as the 2 didn't fit by default. (XLR, needs 48v phantom power).

+

I have the coupler on the right



option 4@@@@: Vibro Veritas v1. plugged into a 30$ startech USB ADC/DAC.

+

the color code follows the measurement rigs in the graphs for pretend clarity^_^. so green is always something measured with the IMM6.
I used the same source and output level for each group of measurements, first set the IEM to output 90dB SPL@1khz, then calibrate each rigs so REW would read 90dB@1khz. I also tried my best to get the resonance spikes around the same frequency when it was physically possible. no calibration, compensation or smoothing was applied. the EARS comes with a DF compensation but it would make no sense to use it for that comparison against RAWs.

Etymotic ER4SR into various rigs:



Sony XBA_c10:



Fiio EX1 (old one):



to my ears, the EX1 has a lot more subs than the ER4SR or the XBA_c10. I hear the ER4SR with an attenuated low end(I EQ it with a +6dB boost in the subs stating around 100hz). the XBA_c10 feels really close to my idea of flat. and the EX1 has the very sort of boosted low end that I adore. so while the quantities are clearly wrong, my Frankenstein rig with the EMC8000+coupler is the only one to follow the general direction of what I'm hearing. the others IMO always show too much subs on sealed stuff and not enough on vented IEMs. and while I can compensate the EMC8000+coupler to push all the low end up by some value and stick closer to perceived response, it's not something I can really control on the other rigs. the only choice would be to have a sealed calibration and a vented calibration. else the results between IEMs really don't follow subjective impressions. so that's something to check for people trying to set up their little amateur system.


all in all, for frequency response graphs only, I'd suggest to stick to the IMM6 and some app. it's cheap, small, practical, and with a little testing done on silicone tubes of various lengths, we can really work out something with most of the resonances close to how they are on graphs from expensive dummy heads. the EARS has the very obvious advantage to make for easy measurements of headphones without making our own "dummy box" for the head. but I'll wait to see if I can solve my issues before advising to buy one(if you get it for IEM measurements, prepare the tweezers to go fishing for tips).
for distortions and stuff like that, there are plenty of microphones with lower noise floor and better overall fidelity than an IMM6. but if cheap stuff could do it all with great results, there would be no need for people to invest in the kind of rig @jude has for HeadFi. at some point, we always have to face reality. pro gears have different requirements and costs. but to have some fun and learn a great deal through experimentation, any cheap solution has something to offer IMO.

What an awesome post, my friend with the cool Python-inspired username I wish I'd found this sooner.

Can I ask where you bought your "fake" 711 coupler? It looks different to the one that @crinacle is now using. Also, is the mod you made to attach your Behringer mic reversible, or did it involve drilling out the thread?

Some random thoughts/questions...

I love what you've done here. Very inventive and enterprising. I'm not sure how significant the Frankensteining step is, because if this coupler is one of those cheap "711-compliant"(?) couplers from taobao, maybe, just maybe(?!) they were never really 711-compliant to begin with My understanding is that the unit (coupler and mic) need to be calibrated as a whole to ensure the correct transfer impedance. The device @crinacle uses can apparently be bought as just the coupler, or coupler+mic, and I understand the mic comes with some kind of calibration curve. So, in theory, if it were properly built and calibrated, the removal of the original mic and replacement with some other mic could mess things up to the point where it might miss some standard impedance response. (In fact GRAS, Larson Davis, AP, etc. say never to remove their coupler mics.) But... other than being a "standard", that impedance response is arguably a little arbitrary. I don't know how you'd ever really validate even a $4.5k pro GRAS coupler - presumably you'd need to insert mics in an awful lot of fresh cadavers to show agreement with the average human inner-ear response?

I wish we had more affordable options for mics in these couplers and your Frankensteining approach could be one way to remedy that. In my (admittedly very limited) experience, cheaper electret mics seem to have high noise floors and early roll-offs in the subs and highs, whereas phantom-powered condenser mics seem to suffer from a lot of AC mains hum. I suspect that any of the mics you used (with the possible judicious use of a compensation curve) would be totally sufficient for FR measurements. I'd bet most of the differences here are due to the differences in the enclosures the mic/IEM finds themselves sitting in. I completely agree with you that the deltas are the all-important thing here (at least, they are for me), so even the MiniDSP EARS are probably ok in that regard.

But... I'd like to be able to look more carefully at THD+N, so I'm wanting to find some intermediate ground between the $50 Dayton/Behringer mics and the $1000+ pre-polarized/pre-amped/filtered BNC-connected mics that are used with the typical audio analyzers. Kit like the APx555 is awesome for measuring electronics, but I think it's overkill (and certainly over my budget) for measuring IEMs.

If you had a gun to your head castle, what would be your next step-up in terms of mic and USB audio interface?

 

[DanWiggins]

What an awesome post, my friend with the cool Python-inspired username I wish I'd found this sooner.

Can I ask where you bought your "fake" 711 coupler? It looks different to the one that @crinacle is now using. Also, is the mod you made to attach your Behringer mic reversible, or did it involve drilling out the thread?

Some random thoughts/questions...

I love what you've done here. Very inventive and enterprising. I'm not sure how significant the Frankensteining step is, because if this coupler is one of those cheap "711-compliant"(?) couplers from taobao, maybe, just maybe(?!) they were never really 711-compliant to begin with My understanding is that the unit (coupler and mic) need to be calibrated as a whole to ensure the correct transfer impedance. The device @crinacle uses can apparently be bought as just the coupler, or coupler+mic, and I understand the mic comes with some kind of calibration curve. So, in theory, if it were properly built and calibrated, the removal of the original mic and replacement with some other mic could mess things up to the point where it might miss some standard impedance response. (In fact GRAS, Larson Davis, AP, etc. say never to remove their coupler mics.) But... other than being a "standard", that impedance response is arguably a little arbitrary. I don't know how you'd ever really validate even a $4.5k pro GRAS coupler - presumably you'd need to insert mics in an awful lot of fresh cadavers to show agreement with the average human inner-ear response?

I wish we had more affordable options for mics in these couplers and your Frankensteining approach could be one way to remedy that. In my (admittedly very limited) experience, cheaper electret mics seem to have high noise floors and early roll-offs in the subs and highs, whereas phantom-powered condenser mics seem to suffer from a lot of AC mains hum. I suspect that any of the mics you used (with the possible judicious use of a compensation curve) would be totally sufficient for FR measurements. I'd bet most of the differences here are due to the differences in the enclosures the mic/IEM finds themselves sitting in. I completely agree with you that the deltas are the all-important thing here (at least, they are for me), so even the MiniDSP EARS are probably ok in that regard.

But... I'd like to be able to look more carefully at THD+N, so I'm wanting to find some intermediate ground between the $50 Dayton/Behringer mics and the $1000+ pre-polarized/pre-amped/filtered BNC-connected mics that are used with the typical audio analyzers. Kit like the APx555 is awesome for measuring electronics, but I think it's overkill (and certainly over my budget) for measuring IEMs.

If you had a gun to your head castle, what would be your next step-up in terms of mic and USB audio interface?

Get a Clio Pocket. For $600 you get a VERY good piece of gear, with great software. THD+N can be measured, frequency response, impedance, sensitivity, waterfalls, etc. Comes with a calibrated mic as well - everything you need to make professional-quality measurements.

I have several APs (from a System one to my workhorse 525 to a loaded 555), CRYSound systems (the standard for production testing), Klippel R&D, and some other gear, but the Clio Pocket gets used a LOT because it's so portable, easy to use, and "plenty good" for just about any measurement you need to make.

 

[JohnYang1997]

What an awesome post, my friend with the cool Python-inspired username I wish I'd found this sooner.

Can I ask where you bought your "fake" 711 coupler? It looks different to the one that @crinacle is now using. Also, is the mod you made to attach your Behringer mic reversible, or did it involve drilling out the thread?

Some random thoughts/questions...

I love what you've done here. Very inventive and enterprising. I'm not sure how significant the Frankensteining step is, because if this coupler is one of those cheap "711-compliant"(?) couplers from taobao, maybe, just maybe(?!) they were never really 711-compliant to begin with My understanding is that the unit (coupler and mic) need to be calibrated as a whole to ensure the correct transfer impedance. The device @crinacle uses can apparently be bought as just the coupler, or coupler+mic, and I understand the mic comes with some kind of calibration curve. So, in theory, if it were properly built and calibrated, the removal of the original mic and replacement with some other mic could mess things up to the point where it might miss some standard impedance response. (In fact GRAS, Larson Davis, AP, etc. say never to remove their coupler mics.) But... other than being a "standard", that impedance response is arguably a little arbitrary. I don't know how you'd ever really validate even a $4.5k pro GRAS coupler - presumably you'd need to insert mics in an awful lot of fresh cadavers to show agreement with the average human inner-ear response?

I wish we had more affordable options for mics in these couplers and your Frankensteining approach could be one way to remedy that. In my (admittedly very limited) experience, cheaper electret mics seem to have high noise floors and early roll-offs in the subs and highs, whereas phantom-powered condenser mics seem to suffer from a lot of AC mains hum. I suspect that any of the mics you used (with the possible judicious use of a compensation curve) would be totally sufficient for FR measurements. I'd bet most of the differences here are due to the differences in the enclosures the mic/IEM finds themselves sitting in. I completely agree with you that the deltas are the all-important thing here (at least, they are for me), so even the MiniDSP EARS are probably ok in that regard.

But... I'd like to be able to look more carefully at THD+N, so I'm wanting to find some intermediate ground between the $50 Dayton/Behringer mics and the $1000+ pre-polarized/pre-amped/filtered BNC-connected mics that are used with the typical audio analyzers. Kit like the APx555 is awesome for measuring electronics, but I think it's overkill (and certainly over my budget) for measuring IEMs.

If you had a gun to your head castle, what would be your next step-up in terms of mic and USB audio interface?

The coupler should always be the same and not to tuned to compensate the mic. Luckily people who makes cheap couplers are actually really close to gras. Friend of mine actually can build +-0.2db difference coupler 20hz-16khz to that of gras. And gras and b&k are not the same to begin with so it's completely acceptable.

However the mic will mess up with the impedance curve. Even it's legit gras/b&k piston transducer if it is 1 inch or 1/4 inch the result will be very different from 1/2 inch in the standard. But the mics are all measured flat in the testing condition. In terms of cheap electret, it's cheap and can work very well upon 6khz in the pressure field with shallow insertion and 10khz when insert deeply. Also there are difference between free field mic and pressure field mics. Pressure field mics basically have more highs roughly 5db at 10k. That's another thing to consider.
One question I don't know whether you have thought or not. It's that why it's either too cheap or too expensive ? Is there options for 500-1000 dollars? Answer is yes of course. One model I know is really really good is rstech. They have the coupler just the same as gras and proper Chinese piston pressure field mic that performs close to gras or bk even tho there is difference but it's really acceptable +-0.5 up to 10k +-1 up to 16k. So that maybe even better than Aco Japan not quite sure.
Noise floor wise, yes they are really high, but thd tho, it's capable of measure most earphones for as low as 0.01%
In conclusion, coupler is absolutely the bottom line, jf the impedance curve is wrong it's all wrong. If the mic is wrong it can work upon some points or can be corrected for some.

 

[JohnYang1997]

Get a Clio Pocket. For $600 you get a VERY good piece of gear, with great software. THD+N can be measured, frequency response, impedance, sensitivity, waterfalls, etc. Comes with a calibrated mic as well - everything you need to make professional-quality measurements.

I have several APs (from a System one to my workhorse 525 to a loaded 555), CRYSound systems (the standard for production testing), Klippel R&D, and some other gear, but the Clio Pocket gets used a LOT because it's so portable, easy to use, and "plenty good" for just about any measurement you need to make.

What about couplers tho. Clio did secretly make couplers but of course does not come with the clio pocket.

 

[DanWiggins]

What about couplers tho. Clio did secretly make couplers but of course does not come with the clio pocket.

http://periodicaudio.com/Research/ - check it out... I designed it to work with the Clio Pocket mic, and be within ~0.5 dB SPL (and 0.3% THD) of my CRYSound and AP525 systems over the audio bandwidth, provided it's printed with PLA (don't use a different material, that will affect the mechanical impedance of the system). So anyone with a printer - or access to a 3D printing service (meaning anyone on the Internet) can get a "close enough" coupler for pretty darn cheap.

There is also a full-size "45CA-type" 3D printable measurement jig there, too - of course, you need to mod the ear plates to support whatever mic you use. I designed it to support the CRYSound 508 couplers (711-compliant units). Easy mod to make it take the CLIO mic or others...

 

[csglinux]

Get a Clio Pocket. For $600 you get a VERY good piece of gear, with great software. THD+N can be measured, frequency response, impedance, sensitivity, waterfalls, etc. Comes with a calibrated mic as well - everything you need to make professional-quality measurements.

I have several APs (from a System one to my workhorse 525 to a loaded 555), CRYSound systems (the standard for production testing), Klippel R&D, and some other gear, but the Clio Pocket gets used a LOT because it's so portable, easy to use, and "plenty good" for just about any measurement you need to make.

Great recommendation - thanks

 

[castleofargh]

Can I ask where you bought your "fake" 711 coupler?

I'm 90% confident it's this one https://world.taobao.com/item/523280856235.htm but I ended up with it after @hakuzen infected me with curiosity in PM and proposed to send me some of his stuff to try them. so only him would really be sure.

is the mod you made to attach your Behringer mic reversible, or did it involve drilling out the thread?

the mic is fine. no going back for the coupler, I clearly ruined it for any other use by completely removing the thread.

I'm not sure how significant the Frankensteining step is, because if this coupler is one of those cheap "711-compliant"(?) couplers from taobao, maybe, just maybe(?!) they were never really 711-compliant to begin with My understanding is that the unit (coupler and mic) need to be calibrated as a whole to ensure the correct transfer impedance

nothing proper, nothing calibrated here(other than using some Etymotic IEMs to calibrate the levels at 1khz in REW). I'm tempted to decide that it's closer to the correct ideal rig because the vented vs sealed response in the subs aligns more with my subjective impressions than the other rigs I have. but that's as far as I'm ready to venture. when making that evil creature, I started pretty bad compared to what I could check on the web(although doing that is in itself quite risky when I don't even know the tip used, the insertion depth, some practice habits from the guy...). but I felt like some resonance was strongly shifted in frequency and I fooled around to try and reduce that shift. basically with insertion depth of the mic and by making stuff to fit over the tip of the mic so that the coupler wouldn't interact with the extruded lines around the mic. filling that up really made a nice improvement, or so I chose to believe ^_^. but clearly it's all MacGyver work. nothing is right.

about the standard itself, like most references in science including the units, they all have some arbitrary parts. I need no ultimate device to be absolutely sure that my ears aren't close to an average. so it rapidly turns into what we want and what we need. professionals can't afford not to have a standard reference(even an approximate one) to work with. but most of what I do is for myself so even the FR compensation curve is mostly me putting a finger in my nose and deciding it should be higher at 3khz. I'm a fake objectivist.

But... I'd like to be able to look more carefully at THD+N, so I'm wanting to find some intermediate ground between the $50 Dayton/Behringer mics and the $1000+ pre-polarized/pre-amped/filtered BNC-connected mics that are used with the typical audio analyzers. Kit like the APx555 is awesome for measuring electronics, but I think it's overkill (and certainly over my budget) for measuring IEMs.

If you had a gun to your head castle, what would be your next step-up in terms of mic and USB audio interface?

Dan's suggestion of the Clio pocket could be pretty cool, although too expensive for me as my only drive here is morbid curiosity. I don't review stuff, I don't publish much of anything, I'm just a kid playing with toys. but I do keep the idea in the back of my head, the same way I've been itching to get a QA400(now 401) audio analyzer since it first came out. if I was to go back to asking for demo products and making reviews, the turnover alone would probably justify getting some OK toys for measurements. but I'm not that guy, it's too much work to properly review gears for free(IMO!!!!).

also I'm really scared that when it comes to measuring IEMs or headphones, investing in quality gears for lower noise and distortions would all be for nothing because of all the noise I have at home. it's all great and fun as long as I'm using my crappy ears, but even achieving conditions to get to the limit of those cheap toys I have, can be a real challenge in my house. unless it's 2AM, not a week end, no rain, no wind (it's impressive how much I don't mind wind and often don't even notice how strong it is until I see the mic picking it up), no drunk people, no dude playing Collin McRae IRL in the mountain road, and I have to remember to turn off my fridge(and more importantly I have to remember to turn it back ON when I'm done^_^).
I have a laggy fanless computer just to measure transducers, so fan noise is a solved issue.
right now I wonder if my best upgrade wouldn't first be to move to another house. for headphones and at least vented IEMs, I suspect it could be a legitimate upgrade.

all that to say that I'm low fi and will probably stay that way. at least until I get tempted by something again.