Symphonium Crimson - One persons two year journey to find the One
First it is important to know this is just a review, one persons opinion (YMMV). The unit being reviewed was purchased by me at CanJam London for full retail.
Who am I, what do I value in audio reproduction and what’s my basis for comparison. Well I started down the audiophile rabbit hole with speakers in 1992 with my first pair of Alon 1 speakers. These were highly transparent but with deep tight bass response. As they years went on I fell in love with horn based speakers like the Altec Lansing Voice of the Theater and more recently OMA (Oswalds Mills Audio) Imperia and Mini as benchmarks.
I fell into headphone listening only due to a change in living arrangements, shorthand for I moved in with a friend and they weren’t going to indulge my audio gear in their living room. In late 2004 I joined Head-Fi as a short stop gap to find headphone audio to fill in this gap. Almost 20 years later I'm still here enjoying the people, music and gear (in that order).
I have owned AKG K-1000a, Grade PS-1, RS-! Pink Drivers (wow try these), RAAL ear speakers, several Stax headphones… My current full size drivers are the LCD-5 and HifiMan HE1kse. In ears I was there for the start of JH audio in 2009 and had 3 of his units (13, 16, Lola), also the Sony ier z1r, FIR M5 and I currently own the 64 Audio U12t and the Sony M9. I’ve auditioned countless IEMs at multiple CanJams and find two truths: 1) the IEM space has seen the greatest qualitative growth in the Head-Fi space over the past 5 year then any other category and 2) the sweet spot for me in IEMs is the $1500 to $2000 range. I have heard a lot of crappy weird sounding IEMs in the $3000 and up range that are just plain wonky. At Can Jam London I was searching for an IEM that could potentially dethrone the 64 Audio. This is a tough ask as they are pretty highly regarded and are normally found in the top 3 or 5 IEMs by reviewers that stack rank al products regardless of price.
I tend to favor a fast dynamic sound but also need deep tight bass that won’t overshoot into the mid range. I listen to primarily Classic Rock, Grunge, some classic metal, Jazz primarily from the golden age of 1957 to 1965 but wander out of that range a bit for great stuff and lastly blues music. I need a transducer that will make my toes tap and cause me to involuntarily smile or air drum without consciously being aware of it. Timbre aka tone quality is vital as I attend many concerts and play guitar and bass (woefully mediocre but joyously) so I have heard a wide array of actual instruments in many different spaces. A touch of warmth is ok but too much and the music loses its drive and vibrancy. So you could say I value PRaT and transparency.
I like to take a few weeks to sit with a piece of gear prior to writing a full review as sometimes gear that wows at a show or in a quick listen can fatigue over time and sometimes the shy wallflower comes to life and reveals greatness after a week or two.
Ok dude enough about you and blah blah blah… Did you like the Crimson or didn’t you?
I tried these pretty much directly following an audition of the Helios SE and then the Subtonic Storm (these are the best I have ever heard). I really liked the newly tweaked Helios and fell in love with the Storm (my wallet said no). I was expecting to be let down as how could test the Crimson directly after the Storm and not be let down? I was not and I was giddy with excitement at how much I enjoyed these.
Bass - This is a tough one as this may be my favorite IEM for bass reproduction and it’s not the quantity but the quality and how low these play. They have nice sub bass reproduction. The bass is fast and you can follow the bass notes extremely well better hear the cane in pitch than other IEMs I have tried. The bass has incredible texture as well. Listen to a Hammond B3 low notes and it brings chills, Charlie Hunter (Everybody Has a Plan Until..) it almost feels like a visceral impact to the body (although that is physically not possible). There is no bass bleed into other regions. Total win for me here!
Midrange - ok for me the test here is guitar, sax, trumpet and vocals. I can be sensitive to upper midrange brightness. This is my one caveat with these in rare instances there can be a touch of glare with some guitar sounds. I have experienced this extremely infrequently and it may just be the recording but for those with a similarly sensitive to this I thought I would mention it. Now for the good and oh I mean great stuff. TIMBRE in spades my friends. Guitars come to life with these in a way not heard by me in an earpiece. Last night I put on Let it Be by the Beatles and there is an iconic solo and the detail, tone and transparency had me feeling like this was the first time haring this song. As I explore my collection over and over gain I am hit with this experience. Vocals are super clean and clear, they come right out of a deep dark silence to appear hanging right in front of you. These also portray vocal nuance like throat or mouth sounds well. I have had several emotional/hair raising moments with these.
Treble - highly extended, at least for these late 50 year olds ears. My hearing has been tested and it is surprisingly good but age does what it does to hearing. I find the treble well executed and may be the reason for the wide stage and detail retrieval. There is a lot of information in the treble with these but oddly it is never overdone or harsh. I can’t fully explain it, it is there when you need it but it doesn’t push the instruments into harsh or exaggerated sounds. This is also an area that provides great instrument location and overtones that can really bring out the quality of the sound.
Dynamics - These are to my ears very fast sounding earpieces with a great degree of accuracy. They may favor newer masters with a fuller range of bass. All in all I found these a lively listen with great macro dynamics and very good micro dynamics.
Separation and Stage - Not sure how they did this in an earpiece but the head stage is pretty wide with sounds appearing extremely well localized in a 180 degree plane from your ears around you. You can tell the designers really focused on driving separation of sounds as you can clearly pick out each instrument in space in a way not present to this degree in any earpiece I have owned. Clarity is second to none (ok, ok, with the exception of the Storm)
Sonic Quibbles - If he mix is weak sauce then bass is not going to be great, my other pieces seem to homogenize this to a degree. There can be upper mid peaks for me, this is most present in guitars in rock music but only shows up infrequently
Fit and Finish - Fit good but I did need to experiment with several tips to get a fit that was comfortable. I settled for now with the AZLA Crystals. Normally I am a medium but due to the larger nozzle size I needed to size down to the MS to get a fit that sealed well and was comfortable. These are pretty comfortable in my ears with no part of the outer shell creating rub spots or pain. I like the look and the forged carbon has grown on me. The 8 wire cable provided to the early adopters is well done and has good flex. I would love an ear wire for the cable around my ear but I can always add one later. I have pretty much exclusively used the 4.4 as both my daps and my usb dongle docs have this as well.
While I have used many songs to audition these over the past few weeks. I largely focused on a few songs I have used over the past 30 years:
- Eric Johnson 40 Mile Town
- RATM - Killing In The Name Of
- Mad Season - River of Deceit
- Miles Davis - Shhh Peaceful
- Led Zeppelin - Babe I’m Going To Leave You
- Bill Evans - My Foolish Heart
Equipment Used - Shanling M6 Ultra, Ibasso DX320 (amp12) and FIIO BTR 7.
The Crimson is somewhat ruthless with the source and the Shanling and Ibasso showed up well with the Crimson. The FIIO sounded a bit harsh and listening fatigue arrived after about an hour and the timbre was just not as good. So all comments are based on the sound I got from the DX320 and M6 Ultra. I did need about 20% more volume subjectively compared the the 64 audio but at no time were the Crimsons hard to drive. I use medium gain on the devices and on the Shanling for instance it never goes much above 20. On low gain maybe 28 is needed so no worries for powering these.
Now on to comparing these to what’s in the current line up. You know you are truly crazy when you take three sets of IEMs with you on a trip to France so you can complete a review

. Comparisons used the above tracks in more of a stream of consciousness approach.
Crimson vs 64 Audio U12t (m15 module) - U12t excellent but softer sounding bass is fatter but also significantly less defined. Treble on the U12t slightly more diffuse and delicate. Greater perception of details and sense of space with the Crimson. Layering better with the Crimson. Greater midrange presence on the Crimson. It takes several seconds to adjust to the change between these two as they deliver very different experiences to my ears. The 64 audio has good technical chops much has a bit of a warmer sound while the Crimson is significantly better technically but somewhat drier. Crimson delivers more tonal information for guitar sounds it is pretty noticeable. When switching back and forth coming from the Crimson going to the U12t the sound felt veiled and a bit closed in. Overall I prefer the Crimson although the mighty U12t is still a top flight IEM. The cost of the U12t new is $2k vs Crimson at $1.5k at release. Buying new I’d tip my hat to the Crimson.
Crimson vs Sony IER M9 - This comparison is a bit unfair to the Sony as it is about $1k new versus the $1.5k new Crimson. Similar to the 64 Audio comparison, the Sony is warm neutral so the Crimson is just so much more open and spacious. There is more kick drum impact on the Sony coming from the lows that are not nearly as controlled as the Crimson. The Sony has a nice warmth that I could see as an alternative to the Crimson on nights when your brain needs a rest or like this morning when I had a bit of a hangover from too many beers in a cafe with a new Belgian friend who loves jazz and plays in a band that plays around the world but like most musicians has a day job. Well this am maybe the Sony was a bit more prescriptive for me than the more incisive Crimson. One thing this comparison has also shown me is once again with three IEMs at $1k, $1.5k and $2k price is not the arbiter of what is best (at least for me). So I’d chalk it up to me preferring the Crimson head to head but seeing a place for the Sony as a backup, more warm alternative to the daily driver of the Crimson.
Conclusion - Well if you’ve stuck with me this far you obviously know the
Crimson has a strong buy recommendation from me. It’s got the edge in transparency, head stage, tonality/timbre, and the bass is right up my alley. CanJam SoCal is right around the corner as of the writing of this review and we’ll likely see a ton of Crimson impressions so you’ll have plenty of others to juxtapose this review with. Thanks for reading and Thanks to Symposium for continuing to push the envelop!!