[iRo-Fi]

Sounds like something i'd enjoy.

How's the comfort, Tom? Not sure if you're allowed to take photos, any size comparisons with something you have at hand? How's the cable, your impressions on it's comfort/MMCX socket/durability?

Also, any thoughts about how Primo 8 compares to new Audio-Technica line?

 

[tomscy2000]

The W40 is the same as the W4R. It manages to sound "better" because it achieves a better seal and placement in the concha more consistently than does the W4R.
 
When it comes to SQ, the UE900 probably comes closest to the Primo 8 in terms of technical performance, but the Primo 8 has the better fit and ergonomics for my ear, as well as a sound signature that I enjoy more. The Audio-Technica ATH-IM04 is also a consideration, and as a "new generation" universal IEM, it is also pretty good, but it seems to take a departure from the classic Audio-Technica house sound, in favor of a bassier sound. I find the Primo 8's bass, despite being lifted above neutral, decidedly less overwhelming than any of its competitors. The UE900, with a clogged bass port, has a similar feel to its bass response, but with the bass port all the way clear (like it's supposed to be), the UE900 sound decidedly more stuffy. I have not heard the Noble 4.
 
My worry about the Primo 8 is that it's noticeably better than the current three/four driver models, but it's not significantly better, and it's tuned for a very inoffensive, relaxing sound. Nothing "catches" the ear on first listen, and though that is actually the hallmark of its superiority over its competitors, I don't believe that it'll necessarily be a cash cow for Nuforce the same way the Triple.Fi 10, UM3X, or SE530/535 were for their respective companies.

 

[tomscy2000]

  How's the comfort, Tom? Not sure if you're allowed to take photos, any size comparisons with something you have at hand? How's the cable, your impressions on it's comfort/MMCX socket/durability?

Also, any thoughts about how Primo 8 compares to new Audio-Technica line?

 
The comfort is good for my ears, at least. It's more comfortable than the W4R, but less snug than the W40. It's about on par with the fit of the SE846.
 
No size comparisons, unfortunately, but I can say that unless you had problems with the previous generation of IEMs in terms of fit, you won't have a problem with the fit on this thing.
 
Cable: The cable is very soft, but I have some concerns about its thickness. Personally, as long as it's durable, I have no problems with thin cables, but the thickness isn't exactly confidence inspiring. I'm also not a big fan of the memory wire portion. It's beefy, but bends stiffly. I'm a little more used to it now, but perhaps I'm still not used to the design. Luckily, the MMCX connector design is excellent, and probably the best one I've seen so far. This design does not swivel [much], because there is a detent that prevents swiveling overbeyond a range of about 30°. However, this means that you have to insert the connector in the correct orientation.
 
I did some quick comparisons with a few earphones, such as the W40, SE846 (White, High Boost Filter), and TO GO! 334, but didn't get to compare it against the IM04.
 
Here are a couple of pictures:
 

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​

 

[HeadphoneAddict]

  Folks, I have the Primo 8 for the night, and then it's gotta go back to the folks at Nuforce tomorrow.
 
Big ups to Wolf for taking the time to meet with me and being generous with letting me handle their engineering prototype (was just told this is a actually a production unit, just not made with the mass production run, so the design and sound signature are finalized, but the build quality isn't necessarily representative of the final production product)!
 
I don't have time to write up full impressions (and even when they come, please take them with a grain [or pinch, I'm better than a grain, I kid, I kid] of salt, because it's basically a 12-hour experience), but I've got a few initial remarks:

1. These are very relaxing to listen to, i.e. they are an IEM that Tyll Hertsens could actually enjoy.
2. I'm impressed by the maturity of Nuforce's tuning choice for this earphone. This is a great first effort on their part, foraying into the higher end of IEMs.
3. TBH, I was not expecting to be impressed, but I am liking them more and more by the second.
4. However, while it is decidedly excellent, it is not quite a "giant killer". It's not taking down the SE846, K3003, or TO GO! 334. What it is, is a very, very competent IEM.
5. The quick summary is that it's "mid-centric", with a mild downsloping response, mild bass, and relaxed treble.
6. Treble is slightly too relaxed for my tastes, but the open stereo separation in the midrange helps with the relaxed sound signature. Timbre is quite natural-sounding, despite the relaxed nature.
7. Primary criticism: accessories are not as polished as those included with the offerings of its immediate competing products from Shure, Westone, and Logitech UE.
8. Secondary criticism: mid-forward sound presentation should probably have slightly more in the upper-midrange and general treble shelf to further delineate the vocal band, which would also allow it to more closely approach the subjective "ideal" eardrum response as outlined by Olive & Welti (2013).

 
(Maybe I should do this Reddit AMA style... ask me anything concerning the Primo 8 within the next hour and a half?)

 
I've also seen the rest of your posts and think you have presented what you hear well - top-tier but not a giant killer, which needs to do everything better, not just mids, etc.  
 
I always fine one area that could be improved in a universal IEM, as mentioned in my review - more treble in SE-530, more upper bass & low mids in TF10Pro, more micro-detail in W4R, less mid-bass in Image X10, more mids in W3, less mids in UM3X, more efficiency in RE-600, more bass in ER4P, or more bass in Primo 8 (about 2 dB). But out of all of these, the Primo 8 may be the most audiophile or "clear and realistic" with live performances.
 
Note - the upper mids and treble is more clear and open with the Westone silicone tips vs the Complys, and so I am now exclusively using the silicone tips. So try to find some of those and give it a try.  They also make insertion into the ears easier. I do agree the cable is pretty soft, but it's not too thin in my opinion.
 
Someone asked about Audio Technica and I've only heard the CK-10 on a 2 week loan, and while others raved about the CK-10, the Primo 8 are superior in terms of the CK-10 being fatiguing and bright to me, while these are smooth like an ER4P, but with more weight and presence to instruments and vocals.  So, maybe not as relaxed sounding as the W4 or RE-600, but much better than the aggressive sounding CK-10 (or Alien Ears C3 customs that I gave away after all the headaches they gave me).
 
The SE-530 you mentioned have great mids but roiled off highs in comparison to the mids, which is what you seem to describe for the Primo 8.  That improves with the tips on both IEM, but the SE-530 mids while smooth as you described are still not as life-like as the Primo 8.  
 
I keep using the term life-like because that's the best way to describe the Primo 8 mids. It's like the micro-detail in the midrange vibrato of vocals is clearer and more present with these. When I upgraded my SE-530 drivers into a custom IEM shell (livewires) I asked for more treble, and now they are slightly sibilant, which takes away from their wonderful mids (the C530 sound like a Grado SR-325i now).

 

[jasonl]

Hi Tomscy, the packaging that you have seen is not the production version. We only have 3 full sets that went to Germany, Singapore and China.  Accessory such as the pouch is genuine lamb skin leather instead of the PU fake leather that you see in practically all the other carrying case and cell phone covers. If it looks perfect, it is not the real thing.  After months of use, PU material can start to wear out.  There will be more coming out from pilot production on March 6 and full production release on March 26.  In production, pilot units are made to make sure everything goes according to plan before mass production.

 

[tomscy2000]

  I've also seen the rest of your posts and think you have presented what you hear well - top-tier but not a giant killer, which needs to do everything better, not just mids, etc.  
 
I always fine one area that could be improved in a universal IEM, as mentioned in my review - more treble in SE-530, more upper bass & low mids in TF10Pro, more micro-detail in W4R, less mid-bass in Image X10, more mids in W3, less mids in UM3X, more efficiency in RE-600, more bass in ER4P, or more bass in Primo 8 (about 2 dB). But out of all of these, the Primo 8 may be the most audiophile or "clear and realistic" with live performances.
 
Note - the upper mids and treble is more clear and open with the Westone silicone tips vs the Complys, and so I am now exclusively using the silicone tips. So try to find some of those and give it a try.  They also make insertion into the ears easier. I do agree the cable is pretty soft, but it's not too thin in my opinion.
 
Someone asked about Audio Technica and I've only heard the CK-10 on a 2 week loan, and while others raved about the CK-10, the Primo 8 are superior in terms of the CK-10 being fatiguing and bright to me, while these are smooth like an ER4P, but with more weight and presence to instruments and vocals.  So, maybe not as relaxed sounding as the W4 or RE-600, but much better than the aggressive sounding CK-10 (or Alien Ears C3 customs that I gave away after all the headaches they gave me).
 
The SE-530 you mentioned have great mids but roiled off highs in comparison to the mids, which is what you seem to describe for the Primo 8.  That improves with the tips on both IEM, but the SE-530 mids while smooth as you described are still not as life-like as the Primo 8.  
 
I keep using the term life-like because that's the best way to describe the Primo 8 mids. It's like the micro-detail in the midrange vibrato of vocals is clearer and more present with these. When I upgraded my SE-530 drivers into a custom IEM shell (livewires) I asked for more treble, and now they are slightly sibilant, which takes away from their wonderful mids (the C530 sound like a Grado SR-325i now).

 
I did try the Westone STAR tips, but only briefly. They're more comfortable, but seem comparable to the single flange tips included with the Primo 8 in terms of SQ. Tried it that way for only a few seconds, however, so I don't know how reliable my thoughts are. Most of the time, I used the the single flange silicone tips.
 
Comply tips are comfortable, but the T series is probably not ideal for sound, as it tends to impart a reverse horn effect when inserted, with body heat causing the foam to expand and constrict the diameter around the exit port. I prefer the round Ts series, which have a tapered mouth.
 
About the bass of the Primo 8 --- from memory, I find that the bass levels are on par with the levels presented in the RE-600, but I haven't done a direct comparison. My preference for bass levels are in the realm of the UERM, which has a bit less bass, but I believe the Primo 8 strikes a great balance in bass response. The nice part about it is that it never feels overwhelming, but can hit hard when the music calls for it.
 
The SE530/535 certainly have rolled-off highs, but they're not as big an issue as people might believe. The Primo 8 certainly extends better, but it's difficult to really test true treble extension accurately in modern IEC60711 artificial ear couplers because of their design; they tend to show a massive drop of about 20 dB in treble response from 16k, for all balanced armature drivers. Because I already have an inkling of what the Primo 8 uses for its treble driver, I trust that it extends well beyond what we need for music. With respect to an approximate neutral response as defined approximately by diffuse field equalization with a 1 dB per octave downslope, the entire shelf from about 5k upwards is relaxed by about 3-6 (more in some minor areas of anti-resonance nulls) dB in the Primo 8; not that I take issue with it --- it's perfectly fine for editorializing music, just not my personal preference. The final result fits very well within the target sound signature of what I assume Nuforce was trying to create, which is a warm, non-fatiguing, but still very clear response.
 

  Hi Tomscy, the packaging that you have seen is not the production version. We only have 3 full sets that went to Germany, Singapore and China.  Accessory such as the pouch is genuine lamb skin leather instead of the PU fake leather that you see in practically all the other carrying case and cell phone covers. If it looks perfect, it is not the real thing.  After months of use, PU material can start to wear out.  There will be more coming out from pilot production on March 6 and full production release on March 26.  In production, pilot units are made to make sure everything goes according to plan before mass production.

 
Thanks for the information. I think it'll be helpful for people anticipating purchasing the Primo 8.
 
I think the pouch I saw is the production version? Indeed, it looks and feels great --- like the feel of a leather wallet (and I was told the leather case actually costs quite a bit to source) truly, but my only concern is that it doesn't provide any impact protection for people who commute a lot and need to carry the Primo 8 around in their bags and backpacks, which is what I assume a lot of people would be doing with IEMs. While the head-fier would not mind the exclusion of a protective case (we have many cases and are constantly looking for better cases to store our gear in), perhaps someone like CNET's David Carnoy would take issue with it.
 
I don't necessarily think it needs to be something as ultra-utilitarian as the Westone Monitor Vault, which is waterproof and crushproof, but a simple foam core insert would go a long way in making that case a lot more bag-friendly.
 
If we examine cases from others:




 
All of these offerings contain some kind of hard or semi-hard inner structure to mitigate the stressors of being inside a bag or backpack filled to the brim with various different things.
 
For example, my daily use pack to and from the hospital is a messenger bag; I always carry a laptop, a folder, a heavy reference book, a couple of smaller reference pocketbooks, power brick, pencil case, and sometimes my Concero HP. I take the subway everyday, and within the crowded rush hour cabins of the Taipei MRT, I'm bound to be jostled around by other riders, putting strain on the IEMs inside my bag. I often carry two pairs of IEMs, a CIEM and a universal, so if I'm listening to my CIEMs, the Primo 8 would be in my bag, getting squashed by Harrison's Principles of Internal Medicine. As HPA might know, I'm exaggerating, no one in their right mind carries Harrison's around town, but you get my drift.
 
I don't necessarily believe it has to be overly complicated like the one used by the K3003 or IQ, as then no one would bother using it and opt to just stuff them in their pockets to save time. Striking the right balance between too simple and too complicated is the difficult part. People should appreciate the effort Nuforce has put into sourcing the leather pouch; however, an evolution of that pouch would transform it from something that merely looks and feels luxurious into something that is simultaneously useful. That would be a great marriage of form and function.

 

[HeadphoneAddict]

 
Quote:

   
I did try the Westone STAR tips, but only briefly.... snip...
 
All of these offerings contain some kind of hard or semi-hard inner structure to mitigate the stressors of being inside a bag or backpack filled to the brim with various different things.
 
For example, my daily use pack to and from the hospital is a messenger bag; I always carry a laptop, a folder, a heavy reference book, a couple of smaller reference pocketbooks, power brick, pencil case, and sometimes my Concero HP. I take the subway everyday, and within the crowded rush hour cabins of the Taipei MRT, I'm bound to be jostled around by other riders, putting strain on the IEMs inside my bag. I often carry two pairs of IEMs, a CIEM and a universal, so if I'm listening to my CIEMs, the Primo 8 would be in my bag, getting squashed by Harrison's Principles of Internal Medicine. As HPA might know, I'm exaggerating, no one in their right mind carries Harrison's around town, but you get my drift.
 

 
Yeah, fortunately for me, all we pediatricians needed to carry around was maybe a Harriet Lane handbook in a jacket pocket. You can see the size of the book in scale with some IEM here.
 

 

[tomscy2000]

These days, most people just carry tablets. I just thought the image of IEMs being crushed under the weight of Harrison's would be somewhat amusing. I'm actually taking a gap year before graduation to do benchwork in a radiobiology lab, so that's why I manage to carry a few more physical books. Still, I maintain my stance because I'm sure many other people also need to carry around a lot of stuff, whatever those things are, and even if they're not heavy, they could very well damage small items like IEMs.

 

[HeadphoneAddict]

  These days, most people just carry tablets. I just thought the image of IEMs being crushed under the weight of Harrison's would be somewhat amusing. I'm actually taking a gap year before graduation to do benchwork in a radiobiology lab, so that's why I manage to carry a few more physical books. Still, I maintain my stance because I'm sure many other people also need to carry around a lot of stuff, whatever those things are, and even if they're not heavy, they could very well damage small items like IEMs.

 
You're gonna think I'm nuts but as a resident I carried around a small pocket-sized Casio clamshell style PDA with keyboard, and I had created a database of pediatric drugs with the mg/kg dosing and usage. That was back in 1989 or 1990 when I started the project.  It was immensely helpful during emergencies for rapid access (vs the laminated 3x5 card with crash meds on it). Now everything you need fits on an iPhone or Android device.  I was doing electronic medical records with an Apple Newton and syncing to a Mac in the 90's, etc.  Technology has been great for doctors.
 
As for IEM cases, I have been buying Westone zipper cases, and then UE aluminum cases, and now the IEM vaults from Westone to protect mine.  I agree it's nice to get a case with your high end IEM, but some people want something soft and flat for a front pants pocket and others want something hard for more protection, So, one choice on shipping isn't going to make everyone happy.

 

[tomscy2000]

  You're gonna think I'm nuts but as a resident I carried around a small pocket-sized Casio clamshell style PDA with keyboard, and I had created a database of pediatric drugs with the mg/hg dosing and usage. That was back in 1989 or 1990 when I started the project.  It was immensely helpful during emergencies for rapid access (vs the laminated 3x5 card with crash meds on it). Now everything you need fits on an iPhone or Android device.  I was doing electronic medical records with an Apple Newton and syncing to a Mac in the 90's, etc.  Technology has been great for doctors.  
As for IEM cases, I have been buying Westone zipper cases, and then UE aluminum cases, and now the IEM vaults from Westone to protect mine.  I agree it's nice to get a case with your high end IEM, but some people want something soft and flat for a front pants pocket and others want something hard for more protection, So, one choice on shipping isn't going to make everyone happy.

Indeed technology has advanced well; you were certainly well ahead of your time!
 
Personally, I think giving people the ability to protect their $500 asset supercedes the convenience of a soft pouch, as a soft pouch really does nothing. If people are still throwing their $500 IEM into their pants or jacket pocket, then they might as well just not use a case. A cord organizing velcro would just do. A soft pouch might prolong the nice iridescent blue finish of the Primo 8, but that might be it. A possible idea would be a hard or semi-hard insert that fits within the confines of the soft pouch. That way, people who want protection get it, and those that don't can just pull the insert out and use the leather pouch.

 

[HeadphoneAddict]

 
Indeed technology has advanced well; you were certainly well ahead of your time!
 
Personally, I think giving people the ability to protect their $500 asset supercedes the convenience of a soft pouch, as a soft pouch really does nothing. If people are still throwing their $500 IEM into their pants or jacket pocket, then they might as well just not use a case. A cord organizing velcro would just do. A soft pouch might prolong the nice iridescent blue finish of the Primo 8, but that might be it. A possible idea would be a hard or semi-hard insert that fits within the confines of the soft pouch. That way, people who want protection get it, and those that don't can just pull the insert out and use the leather pouch.

 
PS: autocorrect changed mg/kg above (milligrams drug per kg body weight) to mg/hg for some reason.
 
As for your other suggestion, I noticed tonight that I have my JH16Pro FreqPhase in a small velveteen draw-string bag INSIDE of the hard shell case that they came with.  I don't specifically recall if that bag came with them or not, but I don't think I've ever bought a small bag like that on it's own, so likely they included both means of carrying the IEM around.

 

[Deviltooth]

I also favour a hard case that is well padded on the inside.  Any IEM that's $200 plus needs protection and it should be included in the purchase price.  Also, multiple different tips (sizes and styles) should be included (Heir got this right); if there are less than 6 different sets of tips then the company is not providing adequate options for the varied ears of the consumer.

 

[tomscy2000]

Let's hope we can see a better fit kit, as well as a more versatile case from Nuforce in some form or fashion. Aside from the unit sent to Audio360, I don't think anyone else has really had an up-close look at the final accessories kit included with the Primo 8. Just as they've done with the uDAC-2, Nuforce could probably release some kind of variant of the Primo 8 that perhaps features a more durable-looking cable, an expanded set of accessories, and other small additions or changes? It's a possibility.

 

[tomscy2000]

A 12-hour Impression of the Primo 8

As the title suggests, I only spent about 12 hours with the Primo 8, as Nuforce had other plans for that particular unit later in the week. These impressions are proportionally short. If I get to have another go at the Primo 8, I'll do a full review, and actually do some interesting comparisons that don't require as much condiment dosing...
 

​

 
 

Build Quality & Ergonomics

 
The shells fit well in my ear, and I have fairly small ears. I feel they fit better than the W4R shells, but the new W40 shells feel a little more snug. Likewise, they fit about as well as the SE846, with the edge going to the Primo 8 for comfort. The Primo 8 is also more comfortable and low profile than the ATH-IM04.
 
The shells feel pretty solid; they don't feel borderline brittle like the old Westone shells or the TDK BA200 shells, but more along the lines of the SE535 shells. It's not perfect, as there are gaps between the two halves of the shells, but hopefully the general production run smooths out these issues. I'll refrain from real judgment until then.
 
Ergonomically, the cable rotates only about 30º because there is a tab that extends into a small recess in the shell, restricting the rotation of the coaxial connector. Well done, Nuforce!
 
The cable is quite flexible and feels very nice, but does come off as a bit thin and fragile, especially when compared to its braided EPIC 2 competitor or thick Shure cable. It should be plenty durable, but psychologically, a lot of people are going to take a look at the cable and worry whether or not they'll need an aftermarket one.
 
The ear guides are big and beefy, and have that "soft-touch plastic" type of feel, but they do feel a bit stiff and difficult to mold to the ear. It's a good thing the cable connector doesn't rotate too much, or else I would've had a terrible time trying to wrap these guides around my ears.
 

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The cables can appear to be kind of thin, especially above the Y-split.​

 

Accessories

 
I'm not sure if what I saw was all that is included with the final retail package of the Primo 8, but here goes...
 
There are four sets of single flange silicone tips (XS, S, M, L), and two pairs of Comply T-100. To me, the silicone tips feel slightly stiff and tacky-feeling to the touch, but once inside the ear they don't feel uncomfortable at all.
 
While I recommend the Ts-100 tips over the T-100 tips because of their reverse horn effects are minimized, the inclusion of Comply as a tips partner is not a problem at all.
 
The TDK BA200, a sub-$150 product, included a pair of Tx-100 and a pair of Ts-100, which seems quite accommodating to me. I'd also recommend throwing in a pair or two of biflange tips to give people a choice. Biflange tips isolate better and usually sound better than single flange tips; they're just somewhat uncomfortable for people that aren't used to them. It could take some research into finding which kind of silicone (texture, consistency) allow for a comfortable-feeling double flange tip. Low-density foam tips are a possibility as well.
 
The storage pouch is made from a very soft lambskin leather that feels very nice. However, it does not provide any crush protection.
 
There are also other "standard" accessories for an IEM of this caliber: two-prong airplane adapter, 3.5-6.3 adapter, cleaning loop/brush, and a nice microfiber cloth. I can't remember if I'm missing anything else.
 
There was a small velcro cable organizer as well, but I don't know whether it's actually part of the accessories set or that it's just something Wolf brought along with him to keep the cables tidy.
 

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Insertion Depth

 
I suggest as deep a fit as is possible, in order to minimize residual canal volume effects on treble resonances/nulls.
 
The experience mirrors the TDK BA200 (and most other balanced armature-based, concha bowl designs) in that I get the best, most coherent and detailed sound with a deep fit.
 

Sound Overview

 
The general sound signature is warm and intimate, but deep and detailed. Highs are relaxed, but still extend well. Bass is mild, perhaps +5 dB over an Etymotic ER4S, and never gets overwhelming in any way. Midrange is fairly forward, with the upper midrange relaxed relative to the lower midrange.
 

What I like about the Primo 8

 
The Primo 8 is not an aggressive earphone; quite the opposite, it's mostly relaxed, though still stays light on its feet with respect to speed. To me, it's designed for listening for long periods. It won't over-stimulate your brain like a JH13 FreqPhase will do. Rather, it's made for those that want to slowly but steadily appreciate their music.

 

What I'm not so hot about the Primo 8

 
The Primo 8, after 12 hours, just doesn't feel like a character-driven IEM. It feels designed to fit a happy medium, more of a product of focus group feedback, rather than the single, concerted vision of a company head, or an expression of a famous house sound. I felt the same way when I heard the the UE900 a couple years ago, and the Nuforce gave me a sense of deja vu. While the Primo 8 strikes a nice, happy medium that should appeal to a broad number of people, it also runs the risk of not appealing to anyone.
 
The second thing is about the upper midrange response. I don't have a problem with the lower midrange being elevated, but it really should be met with a proportional increase of upper midrange elevation, in order to achieve the best accuracy in the most sensitive band of the human auditory system. While people do tend to be a bit overly sensitive in that region and too much boost leads to appreciable ear fatigue, it should probably still be elevated at least a little bit more over what it presents now, and still be in line with the Primo 8's tendency to be a relaxing, non-fatiguing earphone.
 

Soundstage & Imaging

 
Absolute soundstage is very average (likely a reflection of the relaxed treble), but luckily it doesn't ever feel closed in, which is surprising considering how intimate the vocal fundamentals are placed.
 
Stereo imaging is quite good with the Primo 8, especially in the central approximately +/- 75º or so range of pan.
 

Sibilance

 
In keeping with the idea that the Primo 8 is designed for long-term listening, sibilance is not pronounced in any way. It does not mean that there is no sibilance, however, as some tracks reveal the Primo 8 to be a bit crispier in the 6-7k region than the UERM. Luckily, if we translate that crispiness to the time domain, the sibilance occurs very mildly and (more importantly) transiently, decaying away fairly quickly. There's none of that "ringing" that can be heard in earphones like the Ultrasone IQ.
 

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General Comparisons with Other IEMs

 
Sound signature wise, these IEMs are like the BA-equipped twin of the RE-600 --- always composed, and clean as a whistle, but is quite warm, and despite possessing great detail, doesn't present it aggressively.
 
If I only compare it against other quad-driver universal IEMs (have not heard the Noble 4, Audiofly AF180, LEAR LUF-4), then it definitely slots above the Westone W40, perhaps a tiny bit above the UE900 and IM04 (though the reverse argument can be made as well, and I just didn't spend the time comparing), but lags behind the SE846, and the TO GO! 334.
 
The Audio-Technica ATH-IM04 has not been received very well on head-fi; some users have deemed it a poor value because of its reduced clarity over its lower-priced little brothers, the IM02 and IM03, but I give the IM04 a bit more cachet than others do, and it's still a product worth of being a flagship IEM within the Audio-Technica brand. If we compare the IM04 against the Primo 8, a couple things stand out: (1) the IM04 is slightly weightier feeling in the low end while possessing a similar upper quantity, and (2) the IM04 has a more neutral-sounding midrange with respect to tonal balance, but possesses lesser transparency overall.
 
While I prefer the tonal balance of the IM04's midrange, as the upper midrange allows the entire vocal band to sound a bit more natural and less forward/warm than the Primo 8, the appreciably greater transparency of the Primo 8 is a significant advantage. It's just easier to appreciate the subtleties in vocal expression with the Primo 8 --- voices project deeper in the sound space and take up a larger, more accurate portion of the stereo image.
 
I've never been a fan of the Westone 4, and by extension, I don't really like the W40 either. It has never been all that transparent sounding to me, with uneven treble to boot. It's significantly recessed in the upper midrange, while elevated in parts of the lower treble. To me, the Primo 8 is what Westone should've come out with when designing the W4/40. The Primo 8 is hands-down a clear step-up over the W40.
 
No real time was spent comparing the Primo 8 against the UE900, because (1) I didn't have time to do so, and (2) I never get a good fit with the UE900 with stock tips.
 
Even though the SE846 has been well-received, I've not been a fan of it, largely because I don't believe its price reflects its performance. People who want the subwoofer experience in a BA earphone should try out the SE846 at one point or another, however. It's one of the few earphones with a beefy lower bass response that doesn't encroach upon the rest of the frequency range because of its acoustic design. I'm less impressed with the rest of the SE846, though it is still a fair bit more detailed than the Primo 8. I did try the SE846 with the white, treble-boosting filters, however, and that type of brighter response allows the SE846 pull away from the Primo 8 in terms of tonal accuracy. With another filter, perhaps the advantages of this $1000 IEM are less pronounced.
 
The FitEar TO GO! 334 has been a favorite of head-fiers into high-end IEMs. The Primo 8's sound tuning philosophy is actually similar to that of the FitEar 334 --- downsloping. However, the Primo 8 is a little more mild in flavor; the 334 actually has thicker bass and thicker mids. However, the 334 is simply sublimely beautiful in response above 1 kHz, and the Primo 8 just can't match the feel of the 334 --- the FitEar just feels more organic than the Primo 8 --- it's an intangible feel that's hard to describe, but FitEar manages a euphony in the 334 that I find has been difficult to replicate with other earphones.
 
Likewise, the Primo 8 has not been able to keep up with the technical proficiency of my UERM. The two earphones are quite different in sound signature; the Primo 8 is thicker and fuller, but comes up short when it comes to transparency and openness of soundstage. Even the good stereo separation that I laud the Primo 8 for doesn't quite measure up to that of the UERM's. The one similarity that they share is that neither is an "in your face" type of IEM, as neither will feel overwhelming, in spite of the UERM's brightness, and in spite of the Primo 8's forward midrange.
 

Final Remarks (...for now)

 
It's difficult to really assess the Primo 8 in full when only given half a day to do so. I tried my best to tick off all the boxes, and prayed that my experience in a variety of IEMs would help give me some valuable insight into the feel of the Primo 8, but the truth is that you don't buy an IEM for a mere day. From the sound signature alone, it's clear that Nuforce designed this IEM to stay with an user for the long haul, and the Primo 8 would perhaps only prove its true worth in a long-term engagement. It has shown me flashes of it being akin to an Old Faithful in the world of IEMs, and I believe it's a remarkably mature-sounding product, at least in the short time I've spent with it.
 
I'll look forward to spending a little more time with it, as I want to be able to adequately put their assertion of the Primo 8 being a "phase-coherent" earphone to the test. From a superficial level, it seems to work, as transparency and imaging in a crucial area of the stereo image is surprisingly good --- much better than what I would've expected for an IEM with such forward mids.

 

[busyx2]

Honestly, I ordered a Shure 846, had it and it's going back.
 
I wouldn't go into the detail, but if you're interested, please check out the facts, i.e. measurements of SE846.
 
Even the Shure ad is telling the truth, and that's what I heard.
 
Shure ad.