Thanks Alex - miles behind you mate, and doubt I'll catch up. Looking forward to your thoughts on U6 vs U12 when you get the chance.

THAT WAS A MIGHTY LONG REVIEW !!!  

Great stuff. Really useful graphs too. Looking forward to receiving the MAMs for my A12 (they're still a little bassy with the B1 module).

Great review Paul! 

PS, the color dots were just for kickstarter MAMs, as we were coming up with the final solution of how to differentiate left & right. We're doing the top O-Ring in Blue & Red for retail, no risk of wearing off.

Incredibly helpful and well-written review. I have A6 w/S1 module and your review gave me the best insight yet as to what I might gain / lose from MAM or B1. For now, isolation is important to me so I'm staying with S1, Thanks for taking the time to put this together so intelligently!

Thanks all.  Steve - that idea for the O rings is great

Great review, length was ok for me, and appreciate you took time to explain in detail the ADEL tech and how the modules make a difference. 

Awesome review.! Very detailed and personal.
 
Jumped the gun and ordered the A6 a few hours ago...my first ever CIEM...never been an IEM fan but I think reading this review made me more excited!

I hope it is everything you want in an IEM!  When you've had the chance to get used to it, don't forget to drop by and give your impressions.

Thanks you @Brooko. I always enjoy  your reviews (I'm subscribed). I was particularly interested in this one, and you did not disappoint...it didn't seem long to me at all (although since I was looking forward to this review may have something to do with it).
 
I was a bit too chicken to pull the trigger when I saw these on Kickstarter, since that's a lot of scratch to throw at something sight unseen. (sound unheard?) according to the graphs 1964 Audio give, it seems this is the SQ I'd be most interested in. ( I do lean more toward neutrality... my current favorites are the Shure 535, AKG 701 & HiFiMan 400S.) I'm not sure upping the drivers to the U10 would result in the endgame for you, as it looks (from the graph) to be more of a u-shaped tuning...not the best for the mid-range. Of course hearing is believing, and I'll be very curious of your impressions if & when they're able to lend the U10 to you.
 
I did want to ask one thing about the MAM...am I correct in thinking that the MAM more or less gives you a tuning range from the S1 to the B1? (perhaps a bit more given the "all the way" open is closest to your ideal?) These may very well be the endgame I'm looking for as well...
 
Thanks again...your dedication is evident and appreciated.

Hi Jinxy - thanks. Yeah I'm pretty sure with the MAMs you could simulate everything from the S1 to B1 (and a lot in between). The best thing is being able to equalise your ears (if your canals are asymmetric).  If I get the chance to grab a U10 or U12 to compare, I'll let you know

It sounds like the MAMs would indeed be a worthwhile investment. Fortunately for me there is an audiologist not too far (close to where I work actually) that has the ADEL. Looks like I'll be paying her a visit...thanks again!

I purchased my U6's at CanJam SoCal and was very pleased to see your review. I must say I had a very similar reaction, except I don't listen at particularly low levels. I found them a bit dark and had a touch of buyers remorse initially. I finally gave in and also started to EQ mine with my Questyle QP1R. I was centering approx. 1 db lift on 4 kHz and hearing encouraging improvements. But I think you have a better recipe and I'm listening to your curve now. Listening to Nora and Ella... Thank you so much! I need to get back in touch with the fine folks at 64 Audio and find out what ADEL modules were in the demo U6's, they may have been the B1's.
That said, thank you for discussing the different modules in great detail, I am fairly certain that the MAM's or B1's would be more to my taste but I travel by air so much that I would hate to give up the S1's due to their greater isolation. I found that they did not bother or set off my own tinitus problem even after 5 hours listening on a plane last week. They do not isolate as well as my old Klipsch K10 but they still work well enough in flight and and it is nice that they exhibit such low levels of microphonics too. Thanks again for an honest and well researched review.

I have been wondering why they are voiced this way and came up with a couple of ideas. One was that they are designed as stage monitors and for musicians the basic sound would be quite good as it has a lot of rhythm due to its great bass and drum qualities. It is non fatiguing and you can listen at relatively high volume without discomfort. This would be more useful to a performer than the cymbal splashes and other high frequency sounds in the mix. Another was that they were designed to be used with custom earmolds and those might alter the equalization curve as heard by the wearer. I actually avoided customs as I have owned custom earmold musicians earplugs in the past and I prefer a more flexible foam based interface.

Paul... Wow. Your personal journey drew me in and helped me understand your review in a way so rarely achieved when describing audio. Simply an amazing review!

@husafreak - I ahve to admit its kind of reassuring to hear someone else have a similar experience.  If you're flying a lot, get the MAMs.  They'll give you the greatest isolation (dialing them closed), and then you have the option of opening them up when isolation is less of a factor. As far as the voicing goes - I'm guessing the A series (customs) may indeed be a little different (deeper insertion etc).  I guess when I compare with my HD600, T1, HD630VB etc, and many of the IEMs I own, there are very few that aren't flat or have a slight rise through the presence area. If I get the chance, I'll definitely ask Vitaliy about it - as there must be a reason.  Campfire Audio's Jupiter had a similar (but much larger dip) and unfortunately I just couldn't get past it - yet others really like them.  I guess it all comes down to anatomy and preference in the end.  Anyway - thanks for the comments.  They are appreciated.
 
@x RELIC x - Craig  - thanks. I was hoping the "journey" might resonate with someone. I'm more and more coming to appreciate how the wham-bam write a review after listening for a week might in some cases be doing a dis-service to some manufacturers.  Its something I might cover in a blog post

I was able to get the B1 modules to audition. Not the MAM's though. They are I guess all spoken for so still not available for purchase separately. The B1 wins hands down for me. I will admit that the S1 has a nice warm signature, the bass is particularly full and especially the upper frequencies. They also isolate better than the B1's. But the B1 modules are better balanced and the sound really opens up with them. Especially the higher frequencies. They are just easier to hear. For example on something like Jazz At The Pawnshop you can hear the audience sounds and glass tinkling quite clearly where before that stuff was buried. On Havok's Prepare For Attack (thrash metal) you can hear hall reverb and the guitars really bite, they sound correct. On both those examples cymbals are better defined. If you get a chance to compare the modules listen for the cymbal sounds first for the most obvious change. Note that you do not really lose the bass with either module. You do lose the claustrophobic warmth and IMHO darker presentation of the S1. So I will definitely be keeping the B1 modules and doing most of my listening with those. I am trying to decide about the S1 modules as I travel a lot and they definitely isolate better. I went so far as to compare the modules in a Boeing 737 cabin and again today in my homes laundry room. The S1 modules do a better job of insulating you from outside noises. Also on certain recordings the darker S1's can sound pretty seductive.
In closing, these are not huge differences, it is still the same pair of IEM's. But the two modules show the range of tuning the ADEL modules are capable off. They also both retain the wonderful non fatiguing and musical character of ADEL technology. They are easy to enjoy at low or high volumes. The S1's are just too dark sounding for me. The B1 modules hit the sweet spot for sure.

I am thinking there may be a better alternative for listening to music in aircraft cabins. If I return the S1 modules. For instance I have been using Klipsch X-10's for that purpose for many years. They cannot compete with the U6's for sound quality but they are amazing at isolating you from outside noise.

I just use the QC25s when flying most of the time now.  Either those or the q-Jays.

Yeah, in loud environments I think isolation is the first battle to win, sound quality next. My experiment with the U6's was a short deadhead hop, but with either module it is fatiguing to try and listen through the background rumble to the music. This wasn't a problem with my Klipsh X-10's.
This is my regular set when I'm up front: Bose A20 Aviation Headset with Bluetooth. So I am no stranger to noise canceling cans and the relief they provide. I've just never listened to music through them and they are too big to carry except when I am working. Thanks!