Top critical review
Reviewed in the United States on June 25, 2017
This is an update after using the IEMs for two and a half years. The stem of the left bud broke. I have intermittent sound in that bud and must frequently manually twist and/or remove from my ear and re-insert - very frequently. I had problems with the left ear even before they physically broke. I sent the first pair back and received a new pair. Same problem with the new pair. I decided to live with it rather than continuing to deal with it. Now I'm shopping for a new pair. It won't be an AKG. The sound was excellent. But there was always some amount of stress involved in using them because I knew I would be fiddling with them constantly. Great sound. Lousy build quality/reliability/durability/quality control.
My original review:
Here are my initial impressions after using for a couple weeks. I rate 5 stars even though I feel that these IEMs fall short in a couple ares. Overall, I am extremely pleased. The mids and highs are handled by the balanced armature driver and the lows by the dynamic driver. Both drivers are of very high quality. This, theoretically, is the ultimate combination since dynamic drivers are supposedly better at handling lower frequencies while BA drivers supposedly handle mids and highs better. Selecting from a wide range of high quality recordings, I have found that the mids and highs are extraordinarily clear with a mostly uncolored, natural sound - using the reference sound filter. I then tried the high sound filter and found the emphasis on the higher frequencies a bit too much, the sound slightly shrill and brittle - only subtly, though. Returning to the reference sound filter, I was welcomed by the natural but ever so slightly warm sound of the midrange.
There is plenty of punch in the bass and the bass plays plenty loud. There is a slight emphasis to the lower frequencies giving the sound a bit more warmth than perhaps is found in the source material. I will admit that it's possible my previous IEMs (the excellent Shure SE215's) simply weren't capable of producing the lower frequencies as well as the N40's, but I don't believe that's quite correct. I think that the slight emphasis on the lower frequencies is there. Yet, it doesn't detract. I tried the high sound filters to see if I would get a bit more neutral sound signature. There was less bass, but I found I preferred the slightly warmer sound of the reference sound filters. I did not try the bass sound filters because I feel there is already more than enough bass to keep me happy. I will try them at some point because I'm curious how the N40's will handle the greater volume in the lower frequencies. Will the bass remain as tight and in control? Or will distortion become more audible? I suspect they'll still sound quite good.
As previously mentioned, the lower frequencies are handled by the dynamic driver, which is quite different in its approach to generating sound than BA drivers. I feel that this difference shows in the character of the sound in the lower versus middle frequencies and in the transition in the music between these two general ranges of frequencies. It is subtle. It's also possible that I may be guilty of confirmation bias stemming from my awareness of the two different driver technologies present in these IEMs. The use of these two different driver technologies is what attracted me to these IEMs as it offers the best possibility of getting the optimal sound reproduction across the entire range of human hearing in one package (other than, possibly, from planar magnetics drivers like the comparably priced Audeze iSine 10). If the sound character mismatch is indeed there, it is very slight. And, I'm more than willing to accept this as a possible trade-off in getting the best sound.
As an aside, I had considered getting the Audeze iSine 10's, which are reputed to sound better than the N40's. The reason I didn't was because the iSine 10's are open-backed and there's considerable noise bleed. I mainly use my IEMs at the gym and when traveling by plane and I don't see the need to force my listening choices on those nearby. The N40's, like most IEMs, are a closed design.
Regarding sensitivity, my Nexus 6P is able to drive the N40's just fine - in the gym and with most source material. I suspect that I may have a problem on a plane. For that reason, I will likely purchase a light, portable headphone Amp/DAC. I suspect that the listening experience will improve with a Amp/DAC but I will no longer be able to use the N40 cable with in-line control, which I really like. The in-line controls work flawlessly with my 6P: pause, play, skip, volume up and down, and phone calls.
Why do $400 IEMs only come with four sets of only one type of tip? The included tips work fine with my ears. But I would have liked to try foam tips, which have been my preference with previous IEMs. I may purchase compatible foam tips in the future but I shouldn't have to, especially at this price.
The three sound filters are a nice idea but I don't know that they're necessary. Everyone is different, though, and others may appreciate having these options. But, in my opinion, the high sound filter results in sound reproduction that is a subtle step down. And there is more than enough bass with the reference filters, so the bass filters seem unnecessary. I would have rather had more tips. The sound filters was not among the reasons I chose these IEMs. I was drawn primarily by the combination of BA and dynamic drivers.
The N40s fit me fine and they stay in. I'm comfortable with the over-the-ear design. The rubberized cable around the portion that goes around the ear is comfortable. The cable is of high quality, though I'm glad it's detachable as I can see it wearing out after a time. The cable is slightly shorter than I'd prefer but about three inches, but not big deal.
Overall, I'm very satisfied with these IEMs, especially the sound quality, and I recommend them without reservation.