[csglinux]

Hi guys, I'm in the middle of something that I find disturbing... now it's two manufacturers that I have ordered a custom set of IEM's that both sound different from the Universal demo versions of theirs and well, not in a good way. Since I have some of the decent equipment available to me I have fooled around with measurements only to get to the point that there is probably no way to actually meaningfully measure the Universals as it seems there is no dedicated "sound" to it as the differences made by the tip of the Universals and the difference in drivers tubing length in the Customs mess everything up in the end?

This is the post I found here that gave me the inspiration to measure difference of the tips only to find in horror that the difference is huge and Custom sleeve or custom design in general messes up the sound.

https://www.head-fi.org/threads/shu...tatic-earphones.785377/page-207#post-13714398

FYI I use the SpinFit tips with the Universal demos. So, what do you measuring fanatics think about it? Do you agree with me and what do you think should I tell to the manufacturers for them to fix the sound so that it would actually resemble what people hear when they listen to the Universals and want "that sound"?

I'm not a fan of CIEMs. I'll try to explain why below.

Pros of custom IEMs:
1) No pressure on your ear canals. You can wear them forever with no discomfort.
2) Consistent fit and seal. They'll sound the same tomorrow as they do today.
3) Nope, I can't think of any other pros.

Cons:
1) They're expensive.
2) When you get them back from the manufacturer, they may or may not fit you properly. Most manufacturers will happily repeat the process for you until you're happy with the fit and seal, but even then...
3) They will never give you the same level of isolation that you'll get from a UIEM with something like Comply foam tips. (The people that tell you otherwise are simply the ones who couldn't get a proper seal with foam tips. Measurements don't lie and aren't subjective!)
4) They're a total crapshoot in terms of FR. Your ear canals and conchal bowls are unique - as a result, the length of the tubes running from the drivers to your eardrums will also be unique to you. So you'll never know where those resonant peaks are going to land until those customs finally arrive in the post. And then if you don't like the way they sound, good luck getting a refund.
5) Good luck re-selling them when it's time for an upgrade.

To answer your question, yes you should go back to the manufacturer and ask them to re-work it if it sounds radically different to the UIEM you originally demo'd. Some companies, like UE do claim that your CIEM will be tuned to have what they call a consistent "house signature". It's kind of a bold claim though - I don't understand how they can guarantee this when everyone is going to have different sized ears, which is going to necessitate different bore lengths.

 

[Sinusoid]

csglinux, I know what you mean. Regarding UE, I have looked at a video at some point where they did show their way of manufacture and I think they have a valid point - I believe they use a part "The Booth" that holds all the drivers together always at the same tube length and position, I'm a newb but this actually sounds like something every manufacturer should do to be honest. Also, I see manufacturers treating differently the tip of the CIEM's, some do bore a larger hole there that turns into smaller canals that lead to the drivers, some just come out with bunch of small canals opening straight into your ear but every Tip on Universals create a "horn" so if a CIEM does not mimic that, I believe that will be a flaw right there, creating different sound. No? Link to UE video:

 

[csglinux]

csglinux, I know what you mean. Regarding UE, I have looked at a video at some point where they did show their way of manufacture and I think they have a valid point - I believe they use a part "The Booth" that holds all the drivers together always at the same tube length and position, I'm a newb but this actually sounds like something every manufacturer should do to be honest. Also, I see manufacturers treating differently the tip of the CIEM's, some do bore a larger hole there that turns into smaller canals that lead to the drivers, some just come out with bunch of small canals opening straight into your ear but every Tip on Universals create a "horn" so if a CIEM does not mimic that, I believe that will be a flaw right there, creating different sound. No? Link to UE video:

Any (even small) change in geometry or configuration could create an audible difference in the final sound signature. Maybe, as @piotrus-g pointed out, there are ways of controlling your initial listening experience with the UIEM to limit this somewhat, but ultimately you're still rolling the dice with any CIEM.

 

[Sinusoid]

Thank you piotrus-g, i'll check out the T400's, the SpinFit's I use now are provided by the IEM manufacturer.

 

[SilverEars]

I actually agree with crinnicle. Saying FR reveals 99% is an overstatement.

I recall Brooko stated ES ES3 should be similar to Andro. This is not true. They have different technicalities and sound different despite close enough FR.

Try to EQ a very wonky IEM to be similar to another, the results will not be the same. Also all EQ are not equal, some perform better than other. Lotoo PAW Gold has great PEQ, and I've tried others through computer software, and there are differences in performance.

Please try to refrain from making assertions without real hearing experience by looking at graphs.

There are outliers out there like the Hifiman RE400 and 600. Try to compare the graph to what you hear. Doesn't lineup.

I think we are oversimplifying complexities that isn't isn't knowledged well.

EQ is useful in adjustment, but will not make one iem perform the same as another.

 

[SilverEars]

Until the day we can give technical ability score based on what we can read from measurements to make the perfect purchase that we are entirely sure in it's abilities technically, we do not know enough.

 

[csglinux]

Please try to refrain from making assertions without real hearing experience by looking at graphs.

Chill buddy. We're all of us making "assertions" without being 100% backed up by science.
I'm sure most of us here doing measurements have - on at least one or two occasions - also listened to the results.

Yes, two IEMs could measure similarly in a coupler, yet sound different. That still doesn't mean FR isn't the cause of the difference. If they have different-shaped housings, they won't fit the same in the ear and won't have the same FR at the eardrum that they had at the coupler's mic (where it's usually easier to control insertion depth). Also, the experiences you've had with different forms of EQ just shows that DSP isn't perfect and even if it was, EQ implementations obviously vary from device to device. That's entirely expected. That argument also doesn't diminish the importance of FR.

Let's play Devil's advocate for a minute and say there's something else out there more significant than FR. What do you think it is? (Bearing in mind the vast majority of these IEMs all use the exact same drivers.)

 

[SilverEars]

Don't ask me. I don't design iems. Perhaps those in the trade can share insights.

What I was told by one designer was that bore sizes of tips makes a difference, the foam material, ability of the tip bore to bend(was told that was a special ability of spinfits), and there are new drivers put out, and those can perform better.

We have info about acoustic resonance difference of varying ear geometries. How the muscles can effect the auditory system in how sensitively bass is received, etc..

I recall Tommcy created a thread with a master list of BA drivers involved in various iems.

If any know how different BA driver qualities are differentiated? What parameters they look at to be sure of better performance or improvements? This more insightful than the model numbers!

If anybody goes to Can Jams, ask them!

 

[csglinux]

I should probably take back my quote of 99%. It always bugged me that my wife's shampoo claims to make your hair (exactly) 27.8% silkier. I always doubted the accuracy of that number. I'm sure what they meant to say is the shampoo will make your hair somewhat silkier. What I meant to say is that FR is vastly, overwhelmingly the most significant factor (assuming you've taken care of any phase issues between drivers in multi-driver configurations). As @bartzky pointed out, if you have the FR, you also have the impulse response and vice versa. Most current BAs and DDs share the same technology, with the same materials.

You're absolutely right about bore size, foam material, ear canal resonances, etc., but guess what they all affect!?

 

[SilverEars]

Seriously, you get impulse response from FR graph? Explain.

 

[csglinux]

Check out the REW manual, starting on page 6:

http://www.roomeqwizard.com/rewv5_help.pdf

 

[goodvibes]

Thank you Bartzky - its something I've been suspecting for a long time.

Point in case - I just completed a review for the Lyra II. Even some really experienced reviewers talked about the upgraded sound. When i got them here (along with a pair of the original Lyra), I listened with some quick switching, and was almost sure there were very slight differences. My next step was to measure volume to make sure they were matched, and surely enough, they were very slightly out. Volume matched, listened and no discernible differences (to my poor hearing anyway). Next step - left ear-piece from one (Lyra I), right ear-piece from the other (Lyra II), and volume match using the X7ii's channel adjustment. Now listen - perfect stereo image.

Finally - measure on my rig - practically a perfect frequency response match (once volume matched).

Conclusion - expectation bias is an absolute killer (new model- must be better), volume matching is essential, and I trust my measurement rig to be more accurate than the filter my brain puts over everything

Just to throw a monkey wrench into this. Cables sound different and don't necessarily measure so. I know there's debate but let's say if you one hears it that way. Same with tips that do measure the same. One that don't offer significant restriction or absorption.

To the fellow that said his customs don't sound like his audition. Spinfits have a sound as do many tips. When auditioning samples for customs, you need to use a tip that basically stops at the tip of the nozzle to get a decent take. You won't normally see this at shops since it's more trouble but at shows etc, most custom makers use shallow (and not as porous as comply) disposable foams to try and achieve that. Other than one high frequency resonance point possibly shifting due to eardrum proximity, a universal should be representative is auditioned correctly. If you custom sounds a bit leaner and u shaped, you know the inverse of your spinfit which is awesome on some universals like the PP8.

 

[SilverEars]

Cables do measure differently. It's called impedance. What you are hearing is due to impedance differences, placebo, expectation bias, or combination.

 

[Brooko]

Just to throw a monkey wrench into this. Cables sound different and don't necessarily measure so. I know there's debate but let's say if you one hears it that way.

Guess you have the appropriate data where tests were done in a controlled manner (proper ABX) and compared with measurements? I’nm yet to see an instance myself. I agree cables can make a change if the impedance changes enough to affect frequency response, but otherwise they sound the same to me when volume matched properly. Funnily enough they measure the same as well (frequency).

And if you look at most comments re cable changes (generally always subjective and never volume matched comparisons), most reference changes to bass or treble. Those would certainly show up in a frequency chart!

I’d love to have some hard data which shows otherwise - but unfortunately all the “evidence” seems to be anecdotal .......

 

[goodvibes]

Cables do measure differently. It's called impedance. What you are hearing is due to impedance differences, placebo, expectation bias, or combination.

It's called resistance not impedance. A 75 ohm impedance cable doesn't measure 75 ohms on a meter. Impedance is something different but I know what you mean. I've measured their resistances and 2 that measured the same with under .1 ohm tolerance sound different to me. If you're biased not to hear it or your files and/or kit aren't up to it, that's OK for me. See, there's an inverse to every rational. I even allowed for it in my post you decided to respond to and tell me I'm hearing things. (I'll highlight that for you.) You are allowed your's. Please show the same courtesy.