Not sure how that doesn't make sense. It's about as basic as it gets. Obviously the material and headphone change the size and location of the sounds, that's soundstage. How well defined each sound is 'apart' from each other is separation. Notice I don't say distance.

Using this picture to demonstrate:



Notice the blurry text blends together and is not separated well. Each letter is less distinct and if it were a sound, something even less precise, it would be difficult to tell exactly where it was to begin with. The clear letters at the bottom are exactly the same positions, but are separated better. The stage is merely the original word without any blurring. It's shape and position is determined by the original recording and the electronics and transducers between the original recording and your ears.

Think of a line of musicians standing on stage playing towards you. You hear them distinctly because you are in direct line of sight of their sound. Turn them facing away from you and the sound becomes diffuse and much more difficult to locate where one instrument stops and one begins. This is the same concept.

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maxvla said:

Soundstage to me is literally a stage where the sounds are placed. Separation to me is how clearly those instruments are defined in their own space separated from each other. Think of it like a fuzzy picture that slowly comes into focus. The more in focus you are the better the separation is, but the sound stage itself is entirely unchanged. The sounds still come from the same place, they are simply more defined.
By the way, I don't recall any of those IEMs you mentioned being listed with exceptional soundstaging. There are some universals that do, though.

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Oh that makes sense now. We're not on the same page. 
 
The TF10, W4, FX700 and the IE8 has one of the best soundstages. Let's keep on topic.
 

I'd like to mention first that have not heard a custom IEM.
 
To my ears, no universal IEM can compete with can compete with a decent fullsize headphone in SQ. The best of what I heard is the Sony top of the line (I don't remember the model) and the ER-4 (I have heard most of the flagship ones). Most of them have one thing in common, that is the smoothed over sound lacking in texture. I think it has to do with the miniature crossovers for those multi drivers ones (most likely made with SMD stuffs, not exactly high grade). A decent headphone like HD600 or SRH940 would butcher those, they are not even close. If you are willing to pay custom IEM price, it's not even a fair fight.
 
I'd like to stress again that I have not heard those custom ones, but they are made with the same basic technology and I highly doubt that the two technologies can compete. You can't beat the sheer amount of air moved by those full range large drivers.
 
As for sound stage, a headphone's sound stage is pathetic, not to mention IEM. I personally don't put too much hope in them.
 
But of course, if you need absolute portability, IEM is the way to go.

[size=11pt]NavyBlue.  To be honest I was guessing that it would be difficult for custom Iem’s to compete with fullsize. Surprisingly, by the response I am getting, it seems opinion is more in favor of custom iem’s. I haven’t heard customs or any higher end fullsize so I appreciate the response. [/size]

Both have their ups and downs. I personally prefer IEMs, like my Unique Melody, because i'm able to get the best Hi-Fi sounds out of an iPhone and Fiio E7 without bringing a full-size headphone. Generally speaking, I admit many full-size headphones sounds more defined and acurate that many IEMs but I still think there are some amazing IEMs available that are able to compare with headphones. For example, I actually prefer my UM SCL3X remold to many Mid-High end headphones i've listened to like the Sennheiser HD650, AKG Q701, Beyer DT990s, and Grado PS500. IMO all have their own specific details that makes them unique, but I just think my UM sounds better than all of those in sonic signature, comfort, portability, and everything minus soundstage because there is a massive size difference. IEMs don't exactly have realistic bass unlike Headphones, but i'm not a big bass listener myself so i'm not looking for a realistic bass sound in IEMs. It's really your own choice of either a custom IEM or headphones. I'm just saying that I prefer IEMs more because of my mobile lifestyle.

Also with IEMs you have the potential for more detail than full size cans. Yes full size cans do move more air but while moving that air you also lose detailing as it has to move farther from the headphone then into your ear canals while IEMs have to move less air and the IEMs are in your ear canals. And there are IEMs with large sound stages that do compare to full size cans. Maybe not to headphones with the biggest sound stages for headphones but non-the-less; I have out of head experiences all the time with my IE80s and sometimes with my FX700s.
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planx said:

Both have their ups and downs. I personally prefer IEMs, like my Unique Melody, because i'm able to get the best Hi-Fi sounds out of an iPhone and Fiio E7 without bringing a full-size headphone. Generally speaking, I admit many full-size headphones sounds more defined and acurate that many IEMs but I still think there are some amazing IEMs available that are able to compare with headphones. For example, I actually prefer my UM SCL3X remold to many Mid-High end headphones i've listened to like the Sennheiser HD650, AKG Q701, Beyer DT990s, and Grado PS500. IMO all have their own specific details that makes them unique, but I just think my UM sounds better than all of those in sonic signature, comfort, portability, and everything minus soundstage because there is a massive size difference. IEMs don't exactly have realistic bass unlike Headphones, but i'm not a big bass listener myself so i'm not looking for a realistic bass sound in IEMs. It's really your own choice of either a custom IEM or headphones. I'm just saying that I prefer IEMs more because of my mobile lifestyle.

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lee730 said:

Also with IEMs you have the potential for more detail than full size cans. Yes full size cans do move more air but while moving that air you also lose detailing as it has to move farther from the headphone then into your ear canals while IEMs have to move less air and the IEMs are in your ear canals. And there are IEMs with large sound stages that do compare to full size cans. Maybe not to headphones with the biggest sound stages for headphones but non-the-less; I have out of head experiences all the time with my IE80s and sometimes with my FX700s.


 

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mmm headfi logged me out while trying to post. anywho, yes I agree IEMs have crazy amounts of detail at times. My SCL3X http://www.head-fi.org/t/593272/review-unique-melody-re-shelled-scl3x-3-driver-3-way-crossover are my all time fav. I've had them for around 2-3 years already and I am currently 18 so the fit is not an issue for me. I only did minor fixes to my SCL3X by adding clear nail polish onto the monitor itself to make it larger for my growing ears. Be sure to check out the review if you want to reshell or if you just want a Custom IEM

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planx said:

mmm headfi logged me out while trying to post. anywho, yes I agree IEMs have crazy amounts of detail at times. My SCL3X http://www.head-fi.org/t/593272/review-unique-melody-re-shelled-scl3x-3-driver-3-way-crossover are my all time fav. I've had them for around 2-3 years already and I am currently 18 so the fit is not an issue for me. I only did minor fixes to my SCL3X by adding clear nail polish onto the monitor itself to make it larger for my growing ears. Be sure to check out the review if you want to reshell or if you just want a Custom IEM

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I'm already going the custom IEM route. I have my TF10s being reshelled as we speak. I'm also going for the Heir 8A flagship and should have that buy June at the latest. Hopefully within the next couple months if funds permit .
 

 
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jtabq said:

[size=11pt]NavyBlue.  To be honest I was guessing that it would be difficult for custom Iem’s to compete with fullsize. Surprisingly, by the response I am getting, it seems opinion is more in favor of custom iem’s. I haven’t heard customs or any higher end fullsize so I appreciate the response. [/size]

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The problem I have with IEMs, specifically those multi drivers BA IEMs, is actually in the detail department. I suspect that a lot of people who are new in the audio and claim audio nirvana out of ipods have really no idea how real detail sounds like. Many of these achieve "detail" by boosting certain frequencies, akin to an over sharpened picture taken by a bad camera, all the shapes are there but lacking in texture.
 
If you can I'd suggest you compare the followings that has similar sound signature and in the same price bracket, SRH940 vs ER-4, HD650 vs Westone 3, ignore everything else and focus on details, even though all the others are favoring the full size camp. I'd like to see if anyone can look at me in the eye and tell me the later is better than the former in detail out of a decent setup. They are not even close. Actually I'd like to be proven wrong, but I learned the hard way.

RE262 vs HD600 similar price very similar signature.

RE262 wins detail quite easily. I have them both here at my desk.

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maxvla said:

RE262 vs HD600 similar price very similar signature.
RE262 wins detail quite easily. I have them both here at my desk.

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I thought you have sold your HD600?
 

I had two pairs. The first one I broke the headband at the top of the curve. This is the one I still have and the sound is the same, I just can't use it often because it's held together by only the pad. It's rather delicate. I bought a second pair which is the one I sold when I moved to IEMs.

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maxvla said:

I had two pairs. The first one I broke the headband at the top of the curve. This is the one I still have and the sound is the same, I just can't use it often because it's held together by only the pad. It's rather delicate. I bought a second pair which is the one I sold when I moved to IEMs.

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A bit off topic but how is your RE262 compared to the HD600 in terms of timbre?
 
P.S. I moved from IEMs to headphones. I only have iBuds right now.
 

In a quick brief, they share more than they don't. Both are fairly difficult to drive and respond well to amping (the HD600 more than the RE262), the RE262 has the advantage in bass (extension, somewhat in quantity), detail and overall smoothness. Both roll off the highs a good bit but have excellent midrange. Timbre is a bit more realistic on the HD600, but it is very close, close enough it would be personal preference. Hard to be detailed with these since I've gotten used to my UERM which blow both away so they sound quite bad to my ears.

A bit more on topic: I've been struggling with finding a full size headphone under $1000 that would really satisfy me at this point. I thought about going LCD2 with my current rig, but it's just too dark. I heard them at RMAF and they were nice, but ultimately not what I would want. I'm just about decided on going Stax SR507 ($1050) with an energizer, either SRD-7 MKII if I can find one ($200-300) or Woo WEE ($500) to plug into my speaker amp. Electrostats as I said previously win out on detail so this would give me a different flavor than my UERM and can be used by more than me if needed.

i have much more experience with IEMs than full size.  I have lots of universal IEMs, as well as Future Sonics' mg6pro custom IEM and Heir Audio's 8.A custom IEM.
The sound of CIEMs [and high-end universal IEMs] is startlingly full, big, and powerful sounding.  However, I think that certain full sized headphones, at moderately high volumes, probably surpass CIEMs in sheer power and grandness of scale.
 

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