Rhapsodio RDB Mk.IV - Reviews
Pros: Slamming bass, warm and lush mids, super musical and beautiful to look at
Cons: Slightly relaxed treble, not detail monsters
Intro & Me: I'm best described as someone who loves music, loves gear and loves to combine them into a "hobby" that focuses on all of these important ingredients from Head-Fi. I have quite a few IEMs, though I still do not consider myself an audiophile. Instead, I like what I like, I'm not scientific in my "testing" and I am here today to simply give you my thoughts on a really fun, addictive pair of IEMs that I have recently purchased: the Rhapsodio RDB mk4.

Test Equipment:
What I have used for testing in this review is my home desktop setup which is a Gustard A20H balanced DAC/amp, my Pioneer XDP-300r player and my ALO International+ DAC/amp which I use at work. I used Tidal "HiFi" streaming exclusively with tracks from almost all genres, including rock, electronic, country and pop. I used both the supplied cable and also a Rhapsodio RSD Silver cable, which I will go into later.

Ordering, Physical Appearance, Fit and Cables: This time, I'm going to spend a little more time than I normally would on this section because when I took these out of the box, I was blown away. Let's take a step back and talk about Rhapsodio for a minute: they are not Sennheiser. They are not Sony. They are not a large manufacturer. Instead, they are a few extremely talented, friendly and downright awesome folks who share a love and passion for creating some of the best IEMs on earth (in my not-so-humble-opinion). Sammy, who is very well-known on the forums, usually answers messages sent to Rhapsodio inquiring about making purchases. I had never bought a Rhapsodio product before, so I had a few questions that Sammy answered immediately via Facebook Messenger. I love that he's always happy to answer questions and that he's not shy to give his opinion. Truth be told: I had no idea what I wanted, I just knew I wanted a Rhapsodio IEM. The RDB falls on the lesser-expensive side of their lineup and when I asked Sammy how it sounded compared to the Solar and the Galaxy, he replied that he loved it because of its huge dynamic range and great sound quality. When I was ready to order, I got to choose the color I wanted and the overall appearance, similar to a custom IEM experience. I went with an orange shell and carbon fiber face. He sent me photos that blew me away and I was so excited. Then, when I received them, I was just taken aback by how beautiful they were in person, including the Pandora Dwarf copper cable he included with them for me.

The RDB mk4 is the "hybrid" of Rhapsodio's lineup in that it has a single dynamic driver and then four balanced-armature drivers. This sounds like a very potent mix and given the similar configurations, I expected it to sound somewhat like my Shockwave 3 IEMs. I couldn't have been more wrong and that just goes to show that driver configuration is never indicitive of sound quality. The IEMs came in an awesome aluminum case, came with an assortment of silicon tips and also came with a beautiful cable with a leather tie on it. Overall, the package just felt completely awesome. Shipping times were very fast from Hong Kong to the United States and I have no complaints whatsoever.

Let's move onto the fit of these IEMs. They are somewhat large, but very comfortable for me. My preferred tips are JVC Spiral Dots and I am happy to report that these fit the RDB IEMs perfectly. I didn't try any tips that Sammy provided because, why mess with a good thing. Everyone's ears are different and for me, wherever Spiral Dots fit the nozzle, I use them. Unless in rare circumstances I have an IEM where a wide nozzle doesn't work well with the sound, I love them and recommend them. The RDB is no exception, though chances are there's something for everyone in the package.

Sound: Sound is a very subjective thing, but I will do my best to hit all the big points with regards to sound quality and sound signature. Summarizing my take on the IEMs, they are pleasantly dark, musical and very fun with a slamming and deep bass, lush, warm mid-range and a smooth treble that I have never found fatiguing at any volume. These are the IEMs you listen to all day, toe tapping and head bobbing. These are NOT the IEMs you use to hear every single last detail in the music. Now that's not to say they don't produce great amounts of detail, but they stray from the "analytical" side of things in favor of total "musicality" and for that, I love them. Let's dig a big deeper into the different frequencies.

Bass: I think I'm somewhere in between bass-head and north-of-neutral bass preference, meaning I like a lot. I'll just come right out and say it: the bass on the RDB mk4 is the best bass I have heard in regards to my sound preference. The dynamic driver produces a very low, deep sub-bass rumble and still provides an ample punch in the mid-bass. I love, love, love the sound of the lower frequencies through these IEMs. It is well-controlled, deep and definitely more toward fun than neutral. The bass makes itself known sometimes even when the track does not call for it, but not in an overwhelming way. It's just fun and games and like I said, these are not the most analytical IEMs, but darn near the most fun. I rank the bass in the same league as the Velvets I have, where the sub-bass goes a bit deeper on the RDB and the mid-bass on the Velvets is slightly faster and punchier. I guess if I'm splitting hairs, the bass could be a tad tighter and quicker on the RDB, but that also might change the sound signature in a direction that I wouldn't want. These aren't bass-head IEMs, but they're as close as I'm willing to get.

Mids: I really enjoy the mid-range of the RDB mk4. Thankfully all of the wonderful bass I mentioned above does not create any issues with the mid-range on these IEMs. Instead, the mids are warm, lush and vocals sound smooth with enough texture. Electric guitars really sing, with real meat on the bones so to speak and the mids never seem lean or recessed. Male vocals are full and presented with authority and similarly, female vocals are clear, detailed and never sound veiled. The bass blends nicely into the lower mids and I just love the way these IEMs make everything so musical. The mids remind me of my Earsonics S-EM6 IEMs, but not as forward and out in front of the bass.

Highs: To me, the treble on the RDB mk4 is best described as relaxed. The treble is smooth, detailed and relaxed and you will find zero evidence of any sibilance or treble fatigue here. This can be a good thing or a not so good thing depending on the music you choose to listen to. These are not V-shaped IEMs; in fact, I don't even know what shape these would be given the strong bass presence, neutral-yet-warm mids and slightly smooth, relaxed treble. For me, it's uber-musical (sorry for broken record, I'm running out of adjectives) and very enjoyable for long listening sessions. Treble-heads or EDM fans may wish for more treble presence, but the treble I hear is so pleasing to my ears with the right amount of sparkle and character. Symbals and high hats have a wonderful crash that will not pierce your eardrums and pop music has clear, defined high notes. To me, this is very close to the perfect tuning.

Detail, Separation and Soundstage: As I mentioned, these would not be my first choice for an analytical listening session aimed toward eeking out every last detail. I find them wonderfully detailed, but the strong bass presence and warm mid-range may leave some resolution in favor of a more "fun" sound signature. Not a bad thing for me; I love the way these present details and I find no fatigue after spending hours with them. Separation between instruments is very good, but not quite as good as something like the Earsonics S-EM9 (and nor should it be at less than half the price at the time of this writing). Soundstage, however, really surprised me with a very wide stage. I've accumulated a few test tracks that were recorded with a binaural microphone and these IEMs do the recordings justice. While listening with your eyes closed, it is very easy to imagine where each instrument is located and some sound quite distant, while some sound near you. This, for me, is a win on the soundstage front.

Cable Improvements: Ah, one of the most controversial subjects on Head-Fi. I'm going to keep this very simple: I tested these IEMs with two cables. The first, and what I primarily used for a majority of the review, is the copper Pandora Dwarf in 3.5mm single ended. The second cable I tried is the Rhapsodio RSD Silver which I asked Sammy to terminate in 2.5mm balanced. So, while I can't exactly offer an apples to apples comparison, I prefer the RSD silver with the balanced connection. It tightens up the bass, brings the treble a bit forward and generally leaves the mid-range alone. The differences are VERY subtle, but they are there. This cable currently sells for $220 and I think it's a wonderful "upgrade" cable for these IEMs. Once this review is complete, I plan to use the RDB mk4 with the RSD Silver cable indefinitely. Given that the RDB are very warm by nature, this combination really works for me.

Some Comparisons: A lot of folks look for comparisons when choosing IEMs, so I'll do my best here with what I have and what I think some contenders might be. First and foremost...

Earsonics Velvet: The Velvets are one of my favorite pairs of IEMs because of their slamming, authoritative bass and very fun V-shape signature. I actually am finding it difficult to choose a winner on the bass front because they both have such awesome, powerful bass. The bass on the Velvet is quicker, while on the RDB it extends lower and has a softer feel to it. The mids on the Velvet are recessed where they are full and neutral on the RDB. The highs on the Velvet are quite extended and can get bright depending on where you adjust the tuning dial, while the RDB have a smooth, relaxed treble. Someone who prefers a V-shape sound for EDM or pop would likely choose the Velvets where someone who wanted a better IEM for rock and vocals would likely choose the RDB mk4. I give them a completely tie as they are just different sound signatures, but similar quality.

Sony XBA-Z5: Sony's triple-hybrid design with a big dynamic driver and two balanced-armature drivers came to mind in this test because of price point and overall quality. The bass on the Z5 is a bit more refined, though less in quantity than the RDB. Where the RDB bass is seemingly always present, it is there when called for in the Z5. Both extend very deep and are very punchy with kick drums and overall, I think the bass-head would prefer the RDB while someone looking for a slightly more neutral tuning might favor the Z5. Mid-range is a bit warmer on the RDB, while a bit clearer and very slightly recessed on the Z5. Treble on the Z5 sounds energetic compared to the RDB where it is more relaxed and smooth. Z5 leans closer to a V-shape sound with strong, powerful bass, lean mids and extended treble where the RDB is smooth, lush and overall a very dark and warm IEM. I prefer the sound of the RDB mk4 myself. The fit is way better on the RDB for me as well, where the Z5 looks like two USB thumb drives sticking out of your ears!

Noble Django (6): The Noble Django is a six balanced-armature unit tuned toward fun, musicality. Starting with the bass, it is punchy, quick and defined on the Django where it is deeper, a bit looser and slower on the RDB. Again, I think the bass-head would prefer the RDB and someone wanting a bit quicker punchier bass would prefer the Django. The Django has a V-shape signature with recessed mids, where the RDB has warm, lush mids as I mentioned before. Treble is very energetic on the Django and more relaxed and smoother on the RDB. Neither IEM is sibilant or bright, but the treble energy is on a higher level on the Django. This is a tough call as the Django are one of my all-time favorite IEMs. The fact that the RDB mk4 are $350 cheaper than the Noble Django make them a win for me, and I also prefer the dark, rich sound of the RDB. But I can see how someone looking for a more neutral tuning, but still musical an fun, might prefer the Django.

Earsonics S-EM6: The S-EM6 is another six balanced-armature design like the Django, but tuning is completely different. The S-EM6 bass is quite warm and relaxed, though it does not extend as deep as the RDB mk4. It is ever so slightly quicker, but the sub-bass rumble on the RDB mk4 is much better. Mid-ranges are similar here in that they're warm and lush, though the S-EM6 brings the mids forward to be in front of the treble and bass, making vocals sound noticeably forward (and pleasing usually). The RDB vocals are similarly warm and lush, but are not nearly as forward. Treble on the S-EM6 and RDB mk4 might be their most similar traid: relaxed and non-fatiguing. The sound signatures are not too far off in total, with the mid-forward focus of the S-EM6 being the only large differentiator. For me, the IEM for my tastes is the RDB mk4. I love the S-EM6 with certain types of music, but the more versatile and fun IEM is the RDB mk4. Prices vary considerably on the S-EM6 and it's worth noting that I only have the V1 version and not the V2. At retail price of nearly $1k for the S-EM6, the RDB mk4 is an easy winner. At the Massdrop price of $549 that I got them for, it's not as sure a win.

Wrapping Up: I really like Rhapsodio as a company. They're not afraid to step outside the bubble and make IEMs that they think people will love and if it isn't evident yet, I love the RDB mk4. You can see that there are things that I feel some folks might want to change or wish different upon, but these are just so fun for me that I cannot give them any less than five stars. I similarly gave the Velvet five stars because of how much I loved their fun, musical nature and these RDB mk4 are no different (and better in many ways). At the price of $650 including an upgraded Pandora Dwarf cable, they earn my highest mark. At the original retail price of $800 with a Pandora OCC cable, I would probably drop that rating to 4.5 stars. I would still pay it, but, I wouldn't be as blown away as the price to performance ratio that Sammy is now offering with these. In closing, yes there are more detailed IEMs out there and yes, there are more technically superior IEMs out there, but I have yet to hear an IEM that is as fun as these. Now, I've recently obtained a pair of Rhapsodio Solars as well and my statement may change of which of my IEMs are the most fun to listen to, but for right now my ultimate joy is found in the RDB mk4. These are very well done and worthy of your consideration and have turned me overnight into a Rhapsodio fanboy.



  • Like
Reactions: jgosroc and Kerouac
Pros: Amazing (sub)bass and very good (relaxed) sound quality overall. Nice dark signature. Superb build, fit and design.
Cons: Lacks a bit of sparkle in its treble.
Introduction, or how I met my...
Well kids...
I'm not the everyday ''Hey, let's write a review'' kinda guy and because English isn't my main language, please forgive me my grammatical flaws and somewhat limited vocabulary on this one.
I decided to make an exception for the...HEY, WAIT A MINUTE!!!
Complete déjà vu feeling at this moment? PERFECT!
That means that you've at least read the introduction of my Rhapsodio Solar review earlier

But now it's time to write about another Rhapsodio iem, a hybrid (1xDD + 4xBA drivers) one, called the RDB Mk.IV
Information from the RSD site: http://www.rhapsodio.com/products/iem/hybridrdb-series/
- 4BA + 1DD Design
- 3-way passive crossover design, (2 high, 2 mid, 1 bass)
- Frequency response: 20 ~ 20,000 Hz
- Bundles with OFC copper CM cable
- CM socket cables compatible
- 1-year international warranty
Retail price $800
So, how did I got introduced to it?
It started with this imo beautiful pic/design (+$100 for silver carbon fp) posted on Rhapsodios facebook page some months ago:
Not much later, I saw a HF member (productred) describing it in the RSD thread as:
''RDB4: Wild and sexy. V-shape profile that doesn't sacrifice vocals at all (does that even make sense? but that's exactly what's happening here......maybe it's down to adding a pair of mid-range BAs) The dynamic woofer/sub-woofer is THE best out there. No competition. I mean it. Bass coming from that is deep, very impactful, yet magic and voodoos keep it extremely clean and controlled.''
And at that moment the seed was planted in my brain and the damage (for my wallet) was done...it started to haunt me in my daydreams. Would that bass maybe sound something like...

It was obvious that I just had to give it a try somewhere down the line

In the meantime Head-Fi'er @flinkenick picked up the blue one. But some weeks later, he needed funds for other projects (2 expensive ciems). He said I could have a free auditioning (by sending it over to me => a nice oppurtunity and great gesture!) with them and that if I liked it, I could buy it from him. Well, it only took less than an hour for me to conclude that this would end up in a deal.
Build and design:
I still think these look drop dead gorgeous. The beautiful transparent blue shells that show you the drivers inside and the carbon silver faceplate, that gives it a classy look. Build quality is superb (just like with the Solar), couldn't find any flaws on it so far.
The port (for the dynamic driver) is right above the connector, see the small hole over there?
Fit and size:
They're smaller and lighter than the Solar (5 instead of 10 drivers a side) and in footprint comparable in size with (but also slightly thinner than) the Tralucent 1Plus2 that I have.
I put some JVC Spiral Dot (M) tips on them et voilà, perfect fit and seal for my ears.
Cable and source:
As they were bought initially and came to me as shells only, I tried variable cables with it over time. The 2.98 SG cable was my favorite (again), but because that one's already married to my Solar, the RDB Mk4 ended up with the (also excellent) Rhapsodio 8-strand pure silver Luna cable, which I bought recently from another HF member (jmills8)
Listening was mainly done from a Cowon Plenue 1
I'm aware that this is not (sorry for that) a very detailled sound description, like some of you out there can do very well. I guess it's more something like an ''overall abstract painting'' of it.
To put it short: since I listened with the RDB Mk4, its signature always reminded me on my (good ol') Audeze LCD-2, that I had for over a year and loved for its sound quality and signature. I only sold it, because I considered it to be too heavy/uncomfortable in the end. I would describe it as an addictive, ''bit on the dark side'' signature with extremely good (controlled) and deep (sub)bass.
But like productred also mentioned, because of the 2x mid + 2x high BA drivers it doesn't get too dark or muffled and voices still sound pretty awesome with it. There's also still quite a high level of details, instrument separation, soundstage and imaging going on. No, probably not on a Solar level, but also not that far behind. Besides the bass I don't think it excells in anything else, but the overall sound signature of it just keeps on pulling me into the music, which is a good thing.
As mentioned before, the bass is where it really excells. On a bone rumbling deep level => Thors hammer hits with all its earth shaking power when called upon! Mids are a bit recessed, which results in a V shaped signature. Treble is pretty good (never harsh), but lacks a bit of the sparkle (which counts for all my other iems too btw) that the Solar can provide.
But that bass....sigh....that bass. It's just nothing less than legen...wait for it...
If I would have to rank and rate my current (and one former) iems with an overall sound quality score, purely based on my own feelings/thoughts, nowhere getting scientifical at all. It would be like this:
Rhapsodio Solar
9,7 (best allrounder, period!!! No competition in my collection 'till today)
Tralucent 1Plus2
9,5 (amazing soundstage & lows, needed help of a Headstage Arrow 5P to scale up to this level)
Rhapsodio Mk4
9,4 (superb bass and a very addictive dark sound signature)
Sony XBA-Z5
9,2 (very good bass & soundstage, especially for its price)
1964 Ears V6 Stage
9,2 (sold it some weeks ago, beautiful detailled & intimate presentation)
The more expensive Solar is, without a doubt, performing on a higher level. But I found the RDB Mk4 to be a great addition to my small iem collection and I'm still grabbing for it almost every day and have no plans on selling it => I guess that says something.
And because it's that time of the year again...just one more picture to get some inspiration for under (or in) that Christmas tree

Thanks for reading and happy listening to all of you out there!

O man I feel guilty right now...........**SOB**
So you see what I mean about THAT bass huh...............while Rhapsodio, like every major iem makers out there, uses generic off-the-shelf BA drivers, what they truly excel in (where others fall short of) is their in-house dynamic drivers. They have a unique and good understanding of how to make and tune a dynamic driver to sound good, and how to pair them with other drivers to sound coherent. TBH I'm fairly negative towards anything with a decidedly V-shape signature but I find myself unable to fault the RDB4 since the bass is so good yet unobstrusive and the musical picture is still so complete even with such a fun signature.
@flinkenick Thanks mate! I'm not as good as you in describing sound aspects, so chose another direction in ''storytelling''.
@productred Don't feel guilty please, as you did me a favor in the end :)
It must be a very special dynamic driver indeed, producing this sound signature which I like very much! Before this I considered my XBA-Z5 as my best ''bass orientated iem'', but the RDB Mk4 is the new King of the Hill in that department now.
Need moar reviews from @Kerouac, you stylish stylish man. You are an inspiration.