Hydrogenaudio Forums

Quote from: lélé on Today at 11:22:32 AM

Hello!

Sorry for the lack of precision.

I am looking for:

• General information about pros and cons of CIEM vs. UIEM.
• CIEM and UIEM reviews not performed by some audiophile charlatan.

Regarding [1], I am interested in some specific areas:
Sound isolation is very important to me because I suffer from tinnitus. Therefore, I want to keep listening volume as low as possible, including in noisy environments (ex.: in the subway, in a train, etc.). In addition, in quieter environments (ex. : at home, at the library, etc.) I enjoy not being disturb by external noises.
As for the information I found:

• There is a consensus that silicon CIEM provides better sound isolation than acrylic CIEM, which makes sense: silicon CIEM are completely filled while most acrylic CIEM use an hollow shell, silicon is softer and may accommodante slight shape variations thus provide a better seal. Unfortunately, silicon CIEM seem to have a lot of drawbacks: less model choice, lower durability, size constraints, maybe impossible to re-shell (?), etc.
  
• When it comes to compare UIEM and CIEM sound isolation, I found completely contradictory information! Some claim that CIEM sound isolation is far better, while other claim the opposite. I do understand that a lot of parameters comes into play (tips used for UIEM, insertion depth, material, presence (or not) of a vent, etc.). However, I struggled to find data that would give, at least, rough trends. I am looking for that!

Sound quality is also very important to me.
As a long term UIEM user, I noticed that:

• Quality of seal as a tremendous impact on bass response. With UIEM, I usually get the best seal with double/triple flange silicon tips or with foam tips. I do prefer the latter for their comfort. I noticed that my ear canal shape was varying quite a lot when moving my jaw. It seems normal, but to what extent depends - I guess - a lot on individuals. Thus, I was wondering to what extend it could be a problem for me with CIEM (I'll try to discuss that with an audiologist, to check if my ear canal are particularly varying in shape compared to the average individual...). User feedback maybe helpful.
• With UIEM, insertion depth seems to have an impact on high frequency response. I recently read that this may be due to some resonance in the ear canal and that inserting and that modifying IEM insertion depth, thus cavity length and resonant frequency. I was wondering how CIEM manufacturers were managing this issue...and it seems they simply don't! I am looking for more information about that. (Good point with CIEM being that you might get a consistent insertion depth, bad point being that you cannot adjust it.)

Regarding [2], I found a lot of audiophile reviews where facts are mixed with complete non-sense.
On the other hand, we have Chin Roi measurements which provide very interesting material, but they are not easy to understand for the layman (IMHO information about how these measurements impact listening experience are lacking)...and this fellow stopped publishing in 2014, thus most models I am considering are not reviewed.
As for a model short list, nothing is fixed.
Regarding UIEM, I gave a try to Orivety New Primacy (ONP) hybrids (dynamic driver for bass and dual balanced armature for mids/highs). I found them convincing sound-wise, but I had to return them due to comfort issue (my left ear canal as a different slope than the right one and combined with ONP connector implémentation it caused the IEM not to stay correctly in place, no matter the tips used). In addition, isolation was just barely okay. I was also considering second hand Shure SE846 and Westone W60 (these fellows are very expensive but re-sell value is pretty stable in case I don't like them and I have an excellent customer experience with my previous Westome UIEM which lasted 12 years, making the cost of use more acceptable...although nothing guarantee the new ones will last so long !). I also have less expensive options in mind, like the FLC8S (hybrids).
Regarding CIEM, I was considering several options, including AAW because they propose hybrid CIEM and I was curious how to see how they perform after having tried the ONP which were pretty convincing.
But nothing is fixed since I had to rely on those audiophile websites to make my short list...so on unreliable data!

Please take into account that I will use those something like 40 to 50hours per week, in both noisy and very quiet environment.
They are, by far, the listening device I use most...so I pay quite a lot of attention to them.
regards,
Fred

If you are chasing comfort and isolation you shoud go to the audiologist and make several molds with different materials, insertion deepness and concha shapes... and test by yourself what is good for you.

For the UIEM insertion depth issue, you should look at the transfer functions of the 2cc coupler, the 1.26cc standard IEC711 coupler and its diferent adapters (exemple : IEC60318-4 (711) coupler with DB2012 adapter G.R.A.S. 43BA-2, the residual volume is 0.4cc ) and some of the measurements procedures and make your own conclusions.

Some forums have a note (in red text) that pops up in old threads, reminding a poster that it's an old thread.