ROSESELSA RS9039 DAC/Headphone AMP

★ Introduction :-

Roseselsa RS9039 dongle DAC is a newly released by Rose Technics. It is a portable dongle having Newest ESS9039Q2M DSP Chip inside .
For more product info check out their official site below if you interested more on them .
https://rosetechnics.com/

★ Disclaimer :-

This unit was sent to me directly from Rose Technics for review purpose. I had no financial agreement with them to promote their product. As always the entire opinion of this review is completely my personal.

★ Box Content at a Glance :-

The packaging of Roseselsa RS9039 was quite good , a flat black plastic hard case contains dongle dac & a nice looking nylon braided type c to type c short cable. All useful accessories are available out of the box, so there is no need to buy anything extra. Roseselsa RS9039 has no room to complain in this regard

1. Roseselsa RS9039 dongle dac ×1
2. Type c to type c short cable ×1
3. Hard case ×1

★ Design, Build Quality & Functionality :-

In terms of design, this dongle does offer a print design of circuit board outside made out of plastic , but in the build section, it must be called rock solid. This dongle of fully Aliminum alloy constructed which is very light in weight but feels very durable when held in hand. To me it felt like holding a small metal bar in my hand lol. Apart from the solid build, the compatibility of the device was also excellent. I have used it with windows, android without any issues. Interestingly it has support from pcm format to native Dsd 512 which was really commendable.
The device has a small light indicator that changes color according to the audio sample rate. From this point of view, Rose Technics undoubtedly deserves praise.

★ Specifications :-

~ Model :- ROSESELSA RS9039/RS 9039 HiFi Headphone Amplifier DAC
~ Output Power :- 3.5mm 240mw @32 ohms, 4.4mm 300mw @32 ohms
~ Terminating Impedance :- 16-300Ω
~ Input Mode :- USB Type C
~ Output Mode :- 3.5MM + 4.4MM Headphone
~ Frequency Range :- 20Hz-20kHz (±0.5dB)
~ THD :- 0.0003%(32Ω SE)
~ SNR :- ≥126 dB
~ Dimensions: 48mm × 22mm × 12mm
~ Sampling Rate :- 32bit/384kHz
~ DSD :- DSD64/128/256/512
~ DAC Chipset :- ES9039
~ Material :- aluminium Alloy
~ Device Weight :- 14.5g

★ Tested With :-

~ Sennheiser HD660S2
~ Sony IER M9
~ Tanchjim Origin
~ Dunu Falcon Ultra
~ Dunu Kima 2
~ NF Acous NM20
~ NF Audio Ra15
~ Letshouer S08
~ Artti Audio R1

★ Sound Aspect :-

Roseselsa RS9039 basically neutral to slightly warmer sounding dongle. The dongle is able to deliver commendable sound performance from its compact form factor. The low noise floor of the device is relatively quiet, due to which there was no unwanted circuit noise in the background which can be called dead silent noise floor. Due to the lower noise floor, it is able to create a fairly clear invitation to lower frequency sounds naturally. Despite being a performer in the affordable price segment, there was no roll-off issue in its sound which is a big strength.
Roseselsa RS9039 dongle has regular single ended port as well as bal port from where the device can show its max output capability.
Maximum IEM's or some moderate demanding headphones can be powered up with this Bal port to get more juice out.
The dongle has support from pcm to native dsd 512 also supports 32bit/384kHz sample rate.
The Dsd playback is not as expected from budget dongles and this was no exception here.
The dongle has a small light indicator that changes color based on the sound sampling rate but most of the time it creates a confusing situation that can seem a bit annoying.

★ Synergy and Power :-

ESS's 9039 is used as a dac chip in the device, but its sound is not like the typical "ess" house sound. This neutral to smooth sounding dongle has good synergy with almost all types of IEMs.I did not find any decrease in the output power of the device, 120mw@32 ohms from single end and 220mw@32 ohms from Bal port. Despite having such impressive output capability, the dongle is very battery efficient. While using the phone I noticed a very low battery consumption rate which deserves a lot of praise. With this admirable power output, it is possible to power up some demanding headphones in addition to regular dd & planar sets. However, pairing with highly sensitive IEMs was very well, no hissing issue comes easily from here.

★ Conclusion :-

It is good lightweight dongle with neutral smoother presentation who wants their IEM to sound a bit relaxed .

I've provided the purchase link below for everyone convenience

Rosetechnics official website (link isn’t affiliated)

The ROSESELSA RS9039 is a compact sized, portable USB DAC dongle made by the Chinese brand Rose Technics that is best known for their RT-5000 desktop DAC/amp. The ROSESELSA RS9039 is the first USB dongle on the market to feature the brand new ES9039Q2M DAC chip by ESS that features lower distortion and higher SNR performance than its predecessor, the much acclaimed ES9038Q2M.



The ES9039Q2M doesn't have an embedded headphone amplifier so Rose Technics decided to utilize the ES9603Q headphone driver by ESS. The RS9039 is also equipped with low-noise LDO power supply chips to deliver a silent background without audible noise.

The device is plug 'n play compatible with a great range of OS while it supports sampling rates up to 32bit/384khz PCM and native DSD256.

The RS9039 is not compatible with an application, it doesn't have a screen, it doesn't offer any kind of sound customization, it doesn't have volume buttons, gain switch or hardware volume control.



Non Audio stuff

The ROSESELSA RS9039 is a simplistic USB dongle without any buttons or switches so it is more compact and lightweight than most of the competition. It measures 48x22x12mm and weighs 14.5 making it easy to carry around and doesn't occupy much space.

The chassis is made from aluminum alloy with a mate gray-silver finish. The bottom part is flat and has a printed pattern that illustrates the circuit schematics while the top features an asymmetrical design. The RS9039 is a well made, durable and aesthetically pleasing device.



Accessories

The package includes a hard carrying case that might look big but the inside compartment has limited space and is not suitable for carrying the RS9039 together with earphones. I tried to remove the plastic inserts but they are glued both at the lid and the bottom. Except for th case, you also get a USB type-C cable of decent quality. You have the option to order the device with an extra USB type-C to Lighting cable for $10 more.



Power output and efficiency

The rated power output of the ROSESELSA RS9039 is 300mW/32Ω from the balanced and 240mW/32Ω from the single ended output. Plenty of power to run a great variety of earphones and even full sized headphones like the FiiO FT5 or even the Sennheiser HD660S2.

However, the lack of gain setting means that sensitive earphones will become loud too fast and you don't have the option to do fine volume adjustments because the device doesn't have its own hardware volume control. On the plus side, the device is as silent as advertised without any audible noise or cellphone EMI.

Regarding the lack of hardware volume control I have accidentally discovered that the device is compatible with the iBasso UAC application. This means that you get 64 steps of fine volume adjustment.



The power consumption of the RS9039 is 0.11A / 0.55W while idling or playing music at full throttle so it is very efficient and you will not have to worry about your phone's battery duration. The device gets quite warm but not hot even under stress conditions.



Audio stuff

The RS9039 has a neutral-balanced tuning with good linearity, tonal precision and transparency. The sound is characterized by great low-end extension, present mids and vibrant treble that is surprisingly smooth without any annoying brightness. The RS9039 resolves very well for the category and has plenty of energy on tap but it doesn't sound clinical or sterile. The timbre is quite natural without much artificiality or digital glare. This newer generation of ESS DAC chips seem to fare a lot better in this regard than their predecessors.

The technical level is very competitive, the bass is dynamic and impactful, yet tight and controlled with good layering and speed. The textures are not that dry or lean, as someone would expect from an ESS DAC chip, the bass is rather weighty and elastic with strong grip.

The mid-range is clean, transparent and articulated and has excellent tonal accuracy. The sound is not lacking in harmonic variety, instruments and voices are reproduced with convincing realism. The RS9039 is fast and energetic with good definition and plenty of detail retrieval while it sounds quite refined and not coarse or grainy.

The soundstage is class leading for the category because it is spacious and expanded with depth layering and precise imaging. The proximity of the listener to the stage is not too close and the overall presentation quite grand scale.



As per usual practice I am not including any comparisons with other USB DAC dongles, there are too many of them to decide which one to compare or not. You can always read my corresponding reviews and reach your own conclusions. I am including a photo with the Hidizs S9 Pro plus to get an idea about the RS9039 size.

Conclusion

The ROSESELSA RS9039 is a powerful USB DAC dongle with a sonic performance that punches well above its category and doesn't have much to criticize. The criticism has to do with the lack of features that are considered as standard these days, like volume control buttons, gain switch and app connectivity. However, if you don't mind their absence and you need an affordable, lightweight and compact sized USB DAC dongle with plenty of power and stellar sound quality then the ROSESELSA RS9039 ticks all the boxes and is happily recommended.

The review sample was kindly provided free of charge in exchange for an honest review. The price of the ROSESELSA RS9039 is $77.99 and you can find it in HiFiGo.

This hobby is an escapist's dream. Escape from daily routine and distress that's causing you via something as sincere and everlasting as listening to music. I believe that the power of music is still not fully understood since it works in mysterious ways. Allow it to do its magic on you and let your worries dissolve in melody.

Having had the possibility to try so many different sets in a relatively short time I felt obliged to go ahead and express my gratitude by trying to help some lost souls out there, just as I was when I first stumbled upon this weird hobby about wired earphones – so yesteryear! … I thought. Possibilities are seemingly endless and only by getting to meet the right people did I manage to jump onboard the train heading the 'right' direction without getting off-track thousands of times along the way. Make sure to understand the helping person's preferences and you too can find your footing and hit the ground running in no time.

Quick Intermezzo About Me

I won't bore you for too long with personal trivia, however my quick & short background resume goes as follows. Currently I am 27 years old and more in awe of sheer power of music by the day. I have always been moved by music just that slight bit more than average, I'd say. My spending started with a roughly 200€ Bose bluetooth speaker back in my first grade of highschool. What an extraterrestrial thing that was in early 2010s. And it keeps on playing to this day – a true testament of quality. Also sounded fantastic back then, nowadays … yeah, not so much. Lots of BT speakers, TWS, car audio speakers, IEMs, etc., later bring me to this day when I truly consider myself an audiophile. What brings me the most joy beside listening to music is singing, so I am currently participating in a choir and challenging myself with solo vocal covers (check the links in my signature to hear my projects). Unsure where all this leads, but the journey itself is marvelous and life is nothing but a journey.

My preferences lie somewhere in the neutral camp with just an ever so slight bass boost, but I try to keep an open mind and truly appreciate any outliers that dare do it differently. Our ears vary, so do our brain and tastes. I am an advocate for respectful discourse, especially in topics that don't even have many objective undeniable truths. Audio is one of those.

My most listened genres are, in no particular order: jazz, singer/songwriter, slow-paced electronica, ambient, rock, metal, blues, trance, techno & pop.


Disclaimer: I have received the ROSESELSA RS9039 directly from Rose Technics in exchange for my honest thoughts. I am way too mindful of others' money to overly hype stuff that does not deserve it, so there's that.

Here is the link to their website: https://rosetechnics.com/products/r...O3krAvyNse7zzO_zbEMxMu&variant=47078043156785


The Technical Stuff

Who could describe this thing's underpinnings better than Rose Technics themselves, so here are the ins and outs of what this small thing is hiding inside.

That's all nice and fine, but how does it translate to the performance and actual use case, we'll see later.

It comes in a sweet case which I was not expecting:






My Findings About The RS9039

I admit, featuring a dongle is something a bit different for me, but there's no time to lose, let's go. Today's feature is the Roseselsa RS9039 dongle DAC/AMP. I have got a simple yet effective plan worked out on how to present this cute little item.

One of the critical aspects of dongles is battery drain and the fact they dongle and cause stress on your USB-C port of your phone/tablet/laptop. The small size and acceptable weight of the RS9039 minimizes the strain on your port, but some caution is still advised. Pulling this in and out of your pocket is not too difficult, but I don't trust myself to do so, at least not on a regular basis. Getting it caught somewhere and pulling on something is almost inevitable. About the battery drainage, I cannot say I have noticed anything too out of the ordinary, but clearly, this has no power on its own, so it depends on your host device to suck juice from - it is not a heavy drinker, I can confirm.

Since I am sure by now that my most neutral sounding source is the iBasso DX180, I will compare the TONALITY with that one. Only the tonality, because of course, it's only fair not to expect the pinky-sized dongle to be able to compete with the 500USD DAP in any category. Then, I will reach for three (all black, as luck might have it) pairs of IEMs, two of which I have recently reviewed, so I believe I am quite familiar with their sound overall – the tribrid Simgot EW300 HBB and the hybrid Rose Technics Star City 5 Pro. Third one is the impressive and wildly affordable single dynamic driver Tripowin Piccolo, just to see, how far less than 100USD in total (Piccolo currently retails at 9,99USD(!) while the RS9039 is about 75USD) can get you nowadays – spoiler alert: pretty far! Diminishing returns is the term that comes to mind.

Then, to spice it up I will throw at the dongle my full-sized HPs in the form of Meze 109 Pro.



Additionally, I will compare its capabilities to a 24USD Kiwi Ears Allegro Mini which is a TINY thing (can you even spot it on this table?), half the size of the already small Roseselsa.

Without further ado, here comes the tonal comparison with the DX180 after listening to all three IEMs on both.

Tonal Character

Going through some of my favourite and well-known tracks I use in most reviews, the differences are clearly noticeable. Star City 5 Pro gets a slight midbass boost on the RS9039 and just a tad attenuated in sibilance area. Very similar effect can be noticed on the EW300 HBB, while also showing a softer edge in the mid treble on the RS9039. On the Piccolo midrange gets pushed forward a little and some additional hiss is introduced. Simply put, it has no significant negatives compared to the DX180 tonality-wise. Most noticeably, it adds some midbass and smoothens mid treble. Some additional hiss is introduced, especially noticeable on my tablet, where something seems to be incompatible between the two. Alright, so how does all that affect it when going through some songs I consider myself well-versed on?


Song Examples

House of the Rising Sun, alt-J & Tuka

This song has this mysterious vibe going on throughout the song. That is maintained and nicely stretched out in dimensions on the Roseselsa. Then the bass comes in with its multiple drops. Even the lowest of low notes are grippy and tight. That shows this dongle does have some power to maintain control over the movement of the driver even in these most extreme movements. At low to mid volume no distortion can be noticed, while higher there is a bit of a stressed character, but we're talking unlistenable volumes already, at least for longer periods of time. However, even at 100+dB the low end was huge on the Rose Technics Star City 5 Pro – as if these two were made by the same company – oh wait, they are! This duo works very well, since the Star City 5 Pro can be leaning a bit brighter on most sources.

EW300 HBB fits the character of the RS9039 pretty well too. The main reason for that is the slight lack of midbass presence on the EW300 which is now aided. While it is a bit warmer as a result, it still misses the attack and punchiness. Roseselsa does not manage to fix that.

Piccolo is a set that has a very tasteful bass in its arsenal. While the Roseselsa does not necessarily ruin that balance, it does not help improve it either. Lowest notes are impressive for this simple single DD and small yet feisty dongle.


Kuwait, Mazde

A special song that requires good atmosphere and resolution.

Piccolo is so joyous here, just a sweet yet energetic listen, a special marriage between the two. This song is not too midbassy and that helps to get the overall balance into a bit more of a U-shape. No real downsides except some technicalities such as imaging which could be improved – more of an issue of the IEM. Let's hear if that is improved on the Star City 5 Pro.

First seconds of the song were all I needed to see this is improved upon the technical aspect of the previous pairing. We did lose some sweetness in exchange for better sound separation and imaging. It never sounds too busy and crowded. Very well done.

EW300 is like a mix of both worlds and it allows the dongle's strengths to come through. The bass is quite immense. You're not missing a single low note, that's for sure. The crispness is EW300's quality and all the Roseselsa has to do is not ruin it. It does not ruin it, on the contrary, it covers it in a silky dress to make it just that little more polished.


Lonely island, Amble

EW300 and Roseselsa render the guitar naturally but just slightly restrained. His rich and heart-melting voice is maybe only a bit too forward in this case. Let's swap to the other two to get a better idea if that's the IEM's 'fault' or dongle's 'fault'.

Piccolo's guitar playback is not my favourite from the get-go. It then gets even less enjoyable with the very forward vocal. Not too pleased with this song and my source&IEM combo. One more remains.

Star City 5 Pro's guitar is just a tad weighty and wooden too. His voice has an interesting forwardness but gels better with the guitars supporting him, thus the impression it leaves turns out a bit more cohesive and impressive. Either way, since all three sets struggle a tad here, I am afraid strings get a bit too polished and polite on the RS9039. Not that noticeable in usual arrangements, while this stripped down song shows that quite clearly.


And how does it do with the Meze 109 Pro?
Tonally, it's marvelous. The 109 Pro can be quite cold occasionally, but not on the RS9039. I have never liked the 109 Pro off of my other ESS-equipped sources. This goes to show the DAC chips themselves do not tell the whole story. Now, will the little Roseselsa and its 300mW run the 109 Pro to their best dynamic and resolving potential? Not quite. But listening casually is nice too, and for that the Roseselsa does a wonderful job even on these full-sized headphones.

A quick A/B vs the Kiwi Ears Allegro Mini shows the Roseselsa is a more grown up, better thought-out, smoother device. It shows more character, resolves better, allows the ambiance to hover around in a larger setting, and better controls the bass. The smaller and significantly cheaper Allegro Mini leaves a more neutral tonal impression. Vocals are less aggressive, which can either be a good or bad thing, depending largely on the performer and the recording. The form factor is wild and really cute, but it's actually even less friendly to use than the regular dongles, such as the Roseselsa RS9039. I will go into a little more detail on a short review on the Allegro Mini which follows soon.



One negative worth mentioning that I have noticed while A/Bing is that disconnecting the RS9039 from the phone or whathaveyou, makes the IEMs make this 'popping' sound in quite an uncomfortable way, but not dangerously loud. Still, I recommend disconnecting the IEMs or putting them out of your ears before disconnecting the dongle from the host unit.


Summing Up the Roseselsa RS9039

This is one for the dongle aficionados that are lacking a very small dongle which feels of significant quality and does well epsecially with those sets that need a bit of a push in that midbass area and maybe some finesse in the treble. This makes it a coloured source that would not suit all sets or tastes.

Thanks for reading and stay wonderful.

Disclaimer
Please note that I am not an audiophile, and this review does not delve into the technical aspects of the IEMs. My impressions are based on my personal preferences, and others may have different experiences with this product. I also have a very limited experience with audio products so please take this review with a grain of salt.

The Roseselsa RS9039 was lent to me as part of a review tour in the Philippines.

Price: 77.99 USD (or roughly 4.5k PHP)
Link: https://hifigo.com/products/roseselsa-rs9039 (not affiliate)

Part 1: General Product Details

Package Inclusions:

• The RS9039 DAC/Amp
• A USB-C to USB-C cable
• A storage case

The DAC/Amp

• The Dac is made of a bluish-gray cnc-ed aluminum material.
• A 4.4mm and 3.5mm input is on one side and a light indicator on another.
• The Roselsa branding as well as other details are printed in white ink on the top. There is a
• Under seems to be the electronic schematic of the DAC/Amp.
• It weighs 14.6g, and the dimensions is small enough to pocket.

The Storage Case

• A large rubber coated clamshell case approximately 5 times the volume of the RS9039 that can only contain the DAC/Amp and its cable because of a molded base.

The Cable

• It’s a black braided USB-C to USB-C cable, nothing special about it

Part 2: Subjective review



Devices Used
- PC
- Mi Pad 5
- Xiaomi 13T

Headphones Used
- BQEYZ Cloud
- Truthear Hola

General Impressions

• The Hola paired with the warm tuning of the RS9039 elevated the quality of this 20 USD headphones, giving me more rumble
• Meanwhile the Cloud’s bright tuning is toned slightly down, and the bass a bit more emphasized

Comparison vs Hidizs S9 Pro Plus Martha

• RS9039 has sightly better details
• Other than that, both sound very similar to me.

Final Thoughts

The Roseselsa is a great DAC/Amp for the price, beating the Hidizs S9 Pro Plus Martha in terms of power output, size, and value. If you value buttons though, get the Hidizs Martha. If not, the RS9039 is a worthy contender.

Preface:

I would like to thank @gadgetgod and HiFiGo for sending this unit as part of the review tour.

You can purchase RS9039 at the following link (not an affiliate link):
https://hifigo.com/products/roseselsa-rs9039

Also, I’m not a seasoned reviewer or a seasoned audiophile, so whatever I say are purely my observations and your results may vary.

I’m not the one to usually focus on specifications and numbers. I focus more on how happy I am with the equipment’s sound and that’s it.

Specifications:

DAC Chip: ES9039
Weight: Approx 14.5 grams
Dimensions: 48mm x 22mm x 12mm
SE Output: 240mW @ 32Ohms
Balanced outout: 300mW @ 32Ohms

Physical Unit:

The casing is robust made with aluminium, but the design of RS9039 is rather minimalistic. Most noticeably, it is smaller compared to many direct competitors (which can be a good thing depending on how you see it). The device has a simple status light but leaves the physical buttons or volume controls to the possibility of simplicity during use.





Driveability: The device has 3.5mm SE and 4.4mm balanced ouputs. Despite its size, the RS9039 punches above its own weight class quite well. I had no issues driving any IEMs I threw at it even the power hungry Desolation Sounds earbuds. I was also able to drive ZMF Bokeh and Focal Clear MG without any issues.



Sound:

Bass:

The bass response from the RS9039 is tight and well-controlled. It offers plenty of depth with a hefty impact without smearing onto the midrange. The sub-bass extension does it justice with a gratifying rumble that provides ample pleasure to EDM and hip-hop genres without bleeding into the mids.

Midrange:

The strong point of the RS9039 lies in the midrange, which provides clear and detailed vocals and instruments. Resolution is high, and one can pick individual elements from complex tracks. Although it can sound just a bit forward, this can be a bit wearing over the longer term for some people, particularly if you like a more relaxed kind of presentation.

Treble:

While detailed and extended, it can become quite hot (not literally hot) with treble energy on the RS9039, such that it could be declared bright. This adds to the perceived detail and airiness but this also proves fatiguing over long listening sessions.

Tone and Timbre:

Generally, the tone and timbre is on point, although the music tends to be a little more clinical and analytical-sounding. Instruments come over okay, although they don't really have that organic warmth a small proportion of listeners desire.

Staging and Layering of Instruments:

Soundstage is wide and produces a very open sound. Instrument separation and layering are great; you can clearly hear the different sounds and elements in the songs.

Detail Retrieval:

The RS9039 extracts all the details it can. It equally reveals the recording's level of energy, details, and micro-dynamics at the macro and micro levels. It is a very detailed unit for critical listening. Its excellent ability to render complex passages very accurately is just ideal for the demanding music genres, like classical and Jazz.

Conclusion:

The RoseTechnics RS9039 is a standout dongle DAC/AMP, considering the kind of technical performance it offers with a very small and ultra-portable form factor. It is pretty strong in its output and can drive mostly all headphones and IEMs but undoubtedly will appeal to more analytical lovers who like sharp resolution and clear presentation. However, it might not suit many users who are sensitive to high frequencies or look for a more musical sound due to its excessive brightness and lack of organic warmth.

Intro/Disclaimer​

The Roseselsa RS9039 dongle DAC is a newly released portable dac/amp by Rose Technics. It uses the new ES9039Q2M dac chipset.

This dac/amp was loaned to me by a fellow reviewer in the Head-Fi community. Thank you for the opportunity. My review is solely based on what I hear with my own two ears as this is a very subjective hobby. My ratings are also based on how I think this dongle dac fares against others in the same price category.

My primary litmus test when it comes to audio gear is whether or not vocals and instruments sound natural/organic. Regardless if the gear exhibits the biggest bass or the most technical treble. If it doesn’t sound natural to my ears then it’s a red flag.

Packaging and accessories​

The packaging is pretty standard for small budget dongle dacs these days. Wrapped in a cardboard sleeve, inside you will find a hardshell case with the RS9039 DAC and USB-C to USB-C cable. Apple users will need to purchase a Lightning to USB-C connector.

Build & Specifications​

The build of this dongle is quite good actually. Made entirely of a CNC-machined aluminum alloy body, it is very lightweight coming in at only 14.5 grams. The bottom of the dac also has a cool painted-on schematic of the internals. It also distinguishes the 3.5mm and 4.4mm outputs with the words “300MW’ and “240MW”

The RS9039 packs quite a punch in the power department for being such a small dongle. Single-ended outputs 240mW @ 32 ohms and Balanced 4.4 outputs 300mW @ 32 ohms. More than enough to drive even the most demanding IEMs.

One thing you will notice about the RS9039 is the lack of physical buttons. There is no volume control or gain switch. Be Warned!

Output Power: 3.5mm 240mw @32 ohms, 4.4mm 300mw @32 ohms
THD+N: 0.0003% @1 kHz 32 ohms
SNR: 126 dB @ 1khz 32 ohms
Dynamic Range: 130 dB
PCM: Up to 32bit/384khz
DSD: Native DSD 64/128/256

Sound​

Source Chain Used
Pula PA02<-RS9039 <- MacMini M1 <- Apple Music Lossless
Pula PA02<-RS9039 <- iPhone 14 <- Apple Music Lossless
Pula PA02<-Questyle M15 <- MacMini M1 <- Apple Music Lossless
Pula PA02<-Chord Mojo2 <- MacMini M1 <- Apple Music Lossless

Songs played






Initial impressions (before brain burn in)
I usually like to jot down my first impressions within the first few minutes of listening to a new audio product. Because, believe it or not, brain burn-in is a real thing.

Upon listening to the first few songs in my library, I was immediately impressed with the lush midrange and impactful bass. Mid range is smooth and forward. Male vocals have good note weight and sound very lush. The treble is smooth and non-fatiguing but lacking in clarity. You immediately notice that this dac skews more towards a warm/lush sound signature and in turn sacrifices some technical ability. I think this dongle will pair very well with more neutral/bright tuned IEMs.

I did not notice much sonic differences between the 3.5 and 4.4 outputs. Both have plenty of power to drive all your IEMs. I will say that the RS9039 seems to do better with single DD IEMs vs. hybrid IEMs with multiple drivers. It seems to struggle driving the hybrid drivers to their full potential.

Comparisons​

Chord Mojo 2 ($650)

Let’s start off with the Mojo2, it is my benchmark portable DAC/AMP. Yes, it’s in a completely different price bracket but it’s important to have a frame of reference for these comparisons.

When going between the RS9039 and the Mojo2, you immediately notice the claustrophobic soundstage, lack of detail retrieval and poor imaging. Like I said, this was not a fair fight. The Mojo2 is also a warm leaning sound signature but it manages to project a wide soundstage combined with excellent imaging and detail retrieval. The reproduction of music on the Mojo2 is just done with such authority and clarity without ever sounding harsh or sibilant.

Questyle M15 ($250)

Compared to the M15, you also get a more coherent and textured sound presentation. Bass reproduction is tighter, has more texture and slam. The soundstage also opens up, instruments sound very natural and with great separation. Vocals also have a lot more clarity and incisiveness. Overall, a more musical experience when compared to the RS9039.

Apple Dongle USB-C($9)

Last but not least, we have the all-famous Apple Dongle. The Apple dongle is known for presenting an uncolored sound and this time is no exception. Compared to the RS9039, you get much clearer imaging and soundstage. Bass is tight and thumpy but without any bloat. If you want something cheap and good then you can't go wrong with the Apple USB-C to 3.5mm dongle.

Conclusion​

The ROSESELSA RS9039 DAC is an interesting little dongle. It seemingly is a bass boosted/warm dongle dac. Which is not all too common in the world of portable source gear. Most manufacturers go for a neutral based presentation to not color the sound too much. Rose technics threw that recipe out the window and went for their own tuning with the RS9039. And honestly, some people might like this warm coloration to their music. Especially if you have a bright leaning IEM that needs to be toned down a little. All in all, I think Rose Technics have a competitive dongle dac here. This was on sale for $67 at HiFiGo at the time of this writing.

Rose Technics Roseselsa RS9039 Review
I am reviewing the Rose Technics Roseselsa, their current flagship dongle as of this writing.
The Roseselsa costs $80.
I’d like to thank Rose Technics for making me a participant in this tour.
Rose Technics is one of the older companies in Chi-fi, I did encounter some of their products in the past such as the Hybrid 7, and the earbuds Mojito and Masya. I think it was 7-8 years ago. This is my third time reviewing a dongle. I did review Hidizs’ S8 Robin a few weeks back.
IEMS used: BQEYZ Cloud, Hifiman Svanar, and NF-Audio Ne4
Specifications:
ES9039Q2M DAC
4.4mm Balanced & 3.5mm Single-ended Output
CNC-Machined Aluminum Alloy Body
240@32Ω 3.5mm SE / 300@32Ω 4.4mm BAL

Unboxing Experience​

The Roseselsa unboxing was nothing fancy. A black box with a prism reflective print on the front with its specifications on the back. It is more plain when it comes to giving information about the product compared to the Hidizs S8 Robin.

Features​

The Roseselsa has a cool and handy design, as its bottom portion has some electronic like print and it looks cool from my perspective. The overall shape of the dongle is handy and very ergonomic.Though compared to the S8 Robin, the Robin packs more features with its buttons.

Packaging and Build Quality
I do find the packaging rather okay though it is better than the s8 pro when it comes to having more protection as the dongle is encased in a sunglasses-like case which is better for carrying it around. I do find the build quality of the dongle itself above average.
Accessories
Rose wasn’t the most generous when it comes to accessories, it only comes with a Type-C to Type C cable and a hard case. I do think they could’ve included a lightning to type C adapter for older Iphone users. Though I liked the case very much, I do like a silicone protective case for my dongles.


Roseselsa Sound Quality
The Roseselsa is a very competitive dongle for its price. I do believe it has to do with its ES9039Q2M DAC and its 300 mw power output when using Balanced out. Transparent, decent soundstage, good vocals and its scales well with better gear. It still carries a neutral sound, though it emphasizes vocals more compared to the Hidizs S8 Pro. The bass could use a little punch and detail but compared to the S8 pro it does present transparency and more detail. The note weight is thick unlike most ESS powered dongles. When it comes to the treble it does have that ESS like extension though it does not have the “ESS glare” that most ESS powered dacs have. It could use a little more refinement, but I don’t have any complaints at this price point. The Roseselsa is a tad better compared to the s8 Pro when it comes to sound quality.

Synergy
The Roseselsa pairs well with neutral IEMS like BQEYZ Cloud and the Nf-Audio NE4 with its transparent and blue faceplate. It thickens up the sound and gives neutral IEMS life. It also helps some brightness in the treble region as it is a tad darker compared to some dongles.

Conclusion
Rose Technics are venturing to new heights. They are offering a great value dongle because of its sound quality though they sacrificed some accessories in the process. The Roseselsa offers great sound quality at its price and is very competitive. The Roseselsa is definitely one of the better sounding dongles I have tested this year. Very much recommended!

Roseselsa RS9039 Review​

Roseselsa RS9039 Review​

Intro​

Hello everyone, thanks for checking out this feature and review of the Roseselsa RS9039 dongle dac. The RS9039 comes from the audio brand Rose Technics. I was actually happy to receive this device, for a few reasons. For one, I am an unabashed fan of Rose Technics. Always have been. I feel that they craft and create some of the best and most unsung audio gear, or so it seems. Two, the RS9039 sports the absolute latest ES9039Q2M dac chip, which is the successor to the wildly popular ES9038Q2M dac chip. Three, it’s just a dope looking dongle dac and is rated to have some impressive specs. Beyond those reasons, I also cannot help but desire to hear the new thing, and I have an ever-evolving curiosity about what is out there in the world of personal audio. At any rate, I thank the audio store HiFiGo for providing the RS9039 for a feature at Mobileaudiophile.com.

Rosetech Selsa​

Rose Technics actually was founded as “Rosetech Selsa” which began way back in 2012. From what I gather; Rosetech Selsa was derived from an ancient proverb which means “There’s a lot of water yet only one scoop is taken to drink”. Rosetech Selsa has had over a decade of designing earphones while doing their best to maintain a sense of simplicity, like crafting small pieces of artwork. These are actually Rose Technics words (paraphrasing), and I can appreciate this cornerstone fundamental core principle; You can build a company with these words, and so long as everyone buys in… you’ll have a very good and prosperous thing.

Founded​

That brings us to around 2015 which was when the brand “Rose Technics” was founded. Since that time Rose Technics have been crafting one set after another that truly competes against the competition. Especially of late. I have actually reviewed a handful of their iems and have given great marks to each and every one of them. Starting with the Rose Technics QT9 MK2S (QT9 MK2S Review). The Rose Technics QuietSea (QuietSea Review). Then the Rose Technics Star City 5 Pro (Star City 5 Pro Review). Lastly, I reviewed the Rose Technics QT9 Mk3 (QT9 MK3 Review). Each set represents some of the best in each of their respective price points. Especially the QT9 MK3 which is without question one of the best hybrid iems that you can purchase around the $200 range. Rose Technics keeps it simple and usually puts good thought and effort into their products as well.

I know I don’t have to say this, but there really is a mountain of devices beginning to pile up under the $100 price point. Many of which I have on hand to test out and I’d be very interested to hear where they stack up. Well friends, I think I’m ready to see what this little device is all about. The Roseselsa RS9039 everyone…

Full Review can be found HERE​

Non-Affiliated Purchasing Links: ​

–HiFiGo

Disclaimer:​

I received the Roseselsa RS9039 from HiFiGo as a review sample and in exchange I will conduct a full review and feature at Mobileaudiophile.com. I have not received any payment or any other form of compensation for this review. This set is a review sample iem. HiFiGo has not requested to pre-read any review and doesn’t have any control over “what” or “when” anything gets published to mobileaudiophile.com. All thoughts within this review are my own, though please take note that I will always have my own biases. This is impossible to get around. I try to be as objective as my subjective self can be, but this is an opinion piece folks. Thank you to HiFiGo and thanks for reading.

Gear used for testing ​

-Hidizs S8 Pro Robin

-Moondrop Dawn 4.4

-Simgot Dew4x

-A multitude of iems, too many to name here

Packaging / Accessories​

Unboxing​

There’s never a lot to talk about within the packaging of a source device. In the case of the Roseselsa RS9039, it showed up at my door in a smaller rectangular box. It’s a black box to be exact with pinstripes and a holographic sheen of different colors as you move it in the light. Pretty cool, if you are into boxes that is. Anyways, the front cover shows the Rose Technics logo with “Roseselsa” and “ES9039Q2M” underneath. It’s a stylish display I suppose. On the back is a bunch of stats (as usual). Once you slip off the outer sleeve you are met with another black box. Inside that black box is the case that the RS9039 comes in. Rose Technics always hands out some cool accessories, but this is a case where we really don’t see much. You’ll notice that when you open the case the RS9039 will be sitting pretty inside of a felt molded pocket. The type-c data cable is right there too. That’s about it. Nothing that will blow your mind.

Carrying Case​

This kind of surprised me. I don’t usually ever get carrying cases with my dongle dacs and other source devices. In this case, Rose Technics provides a larger black rectangular rubber coated case with a hinge and a snapback style open/shut mechanism. It’s very satisfying actually. The case itself is roughly about 4.75” in length, by 2.5” inches in width, and 1.5” in height. It’s a good size. However, with the molded cut-outs inside you cannot bring anything other than the RS9039 with you anywhere. I guess you can rip the molded guts out and that will give you enough room for a pair of iems, the RS9039 and some other smaller accessories. I love the soft rubber feel on the outside of the black carrying case. It’s actually a nice extra add-on. Again, this is not the norm. However, they also didn’t provide any other adapters or cables which would have been nice. Granted, I personally have every adapter I’d ever need but for those who don’t they’d have to purchase those separately. Nice case though.

Cable​

Not much to say about the type-c to type-c cable. Thankfully the RS9039 does have a cable that I can swap out if need be. I will say that the included black cable is one of the nicer cables I’ve gotten with a source device. It’s very pliable, but also not flimsy. Strong enough to hold the RS9039 without bending at the strain relief. The outside covering is a soft black fabric as well. In length the included cable comes in at just a hair over 4”. It’s not a bad cable at all. Not up to the standards of the cable that came with the Aful SnowyNight and EPZ TP50, but much better than almost every other cable I’ve gotten. It has just enough rigidity, but not too much. I like it.

Specifications​

General Info.

-Brand: Rose Technics

-Model name: Roseselsa RS9039

-DAC chip: ES9039Q2M

-Dimensions: 48mm x 22mm x 12mm

-Approximate weight: 14.5 grams

-Output Option: 3.5 single ended, 4.4 balanced

Sound Parameters

-Output Power: 3.5 se- 240mw @32 ohms, 4.4- 300mw @32 ohms

-THD+N: 0.0003% @1 kHz 32 ohms

-SNR: 126 dB @ 1khz 32 ohms

-Dynamic Range: 130 dB

-PCM: Up to 32bit/384khz

-DSD: Native DSD 64/128/256

Build / Design / Internals​

Build Quality​

Rose Technics usually gets this area right, all the time. Once again, they’ve crafted a device that’s built very well. Made 100% out of aluminum, the RS9039 is a very robust and sturdy little guy. Coming in at roughly 2” in length, about 1” wide and a ½” at its fattest portion in the body which houses the 4.4 port. The RS9039 only weighs 14.5 grams which means it will not overly stress the usb-c port on your phone or computer…even if you let the dongle dangle. Ha. Anyways, it’s not heavy but it is very durable and well made. You can see there’s a 3.5 single ended port as well as a 4.4 balanced port on the thick side and a lone usb-c charging/data port on the other side. There is also a small indicator light as well on the side of the unit. To be honest, the build is fantastic. You’d be very hard pressed to find build quality that is much better.

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No buttons? ​

However, Rose Technics did negate a few things that the community greatly desires and that is buttons of any kind. People in this hobby love control! It’s almost an unspoken truth. We love control. Give us buttons. We want to control the play/pause, skipping tracks, gain modes, and sound filters. These are things that hobbyists desire. I may be some sort of an outlier as I don’t mind this at all because I always control volume, play/pause, etc. at my phone, for the most part anyways. Still, having “gain modes” at my fingertips would’ve sent this dongle dac into the “tops in class” category. However, this is a huge omission for some folks. That’s not just coming from me. I did an “Initial Impressions” post on Facebook, and I got more than a few personal messages about the lack of buttons. I suppose this keeps the price down. That’s one way to look at it. Also, if one could simply look at this device how they look at something like the Moondrop Dawn 4.4, Shanling UA2, Fiio KA3 etc. then you may come to the conclusion that I came to… “It’s not really a big deal and I’m not missing much”. I’m not you though and these functions may be integral in your listening experience. So yeah, no buttons. Is this a deal breaker to you?

Design​

I have to say, the RS9039 is one of the better-looking dongle dacs on the market under $100. I love the aerodynamic and streamlined shape. It’s a dope look in my opinion. The writing on the top side looks classy and not cheesy. You’ll see the Rose Technics logo followed by the name “Roseselsa”. Next to that is the name of the dac chip “ES9039Q2M”. Turn the RS9039 over and you’ll see a schematic blueprint style drawing of the Internals which is a tough look. Really a cool thought and a nice design feature. To be honest there really isn’t a ton to say. The designers did a bang-up job on this device, and they should get some recognition for that. Nice work.

Internals​

I’ve already spoken of what is inside this device quite a lot already. The dac chip used is the ES9039Q2M. This chip is the follow up from the much loved and widely used ES9038Q2M dac chip. At the outset it doesn’t seem like a huge improvement but the amp section on the newer chip is quite a bit bigger and more powerful. Also, the dynamic range is boosted at 130 dbs, signal to noise ratio is much better at 126 db’s, 32-bit PCM and up to 384khz decoding. These chips will only get you so far though. Everytime a company decides to use a chip it has to actually be implemented well. This is true for any dac chip. Yes, it has some refined capabilities and has the potential to really make a device great. Again, if it’s implemented well. There’s also a low-noise LDO power supply chip used among other Internals that you don’t care about.

Features​

Note: The Roseselsa RS9039 doesn’t really have a bunch of actual features on board. This is really just a plug n’ play device which works as it should. There’re no buttons, sound filters or any other notable feature to discuss.

Driving power​

Due to the lack of some more notable features, I figured I’d add in “Driving Power” to the features portion of this review. This is one key aspect of the RS9039. Promotional material states that the RS9039 can get up to 240mw @ 32 ohms on 3.5 single ended, which is quite a lot compared to other dongle dacs out there. 240mw should be able to drive darn near any iem out there. Now, on 4.4 balanced listening the RS9039 can push up to 300mw @32ohms. Both are huge numbers for a dongle dac. Certainly, on paper the RS9039 is one of the more powerful devices in this dongle dac form factor. Without question my Samsung Galaxy Z-Fold 5 was able to provide the best listening experience short of plugging the RS9039 into an actual computer. Many devices nowadays don’t have the current capacity to push these dongle dacs to their best output. However, even if I attached the RS9039 to my daps, like the iBasso DX240, it is still able to power every iem that I tested with with relative ease.

Plenty in the tank​

One thing I did notice is that I was using more volume steps to reach the same loudness levels as some other dongle dacs. In fact, the RS9039 reached equal volume with the Simgot Dew4x. Of course, power and volume are two different things. Just something I thought I’d share. The truth is, the RS9039 is able to power every planar iem that I own very easily and with very good dynamics. Sets like the Hidizs MP145, Raptgo Hook-X, Letshuoer S15, Letshuoer S12 Pro, and Letshuoer S08, BASN Asone, and many many more. Too many to name here. I found the RS9039 is able to drive each set well and with headroom. At the end of the day, I feel that the RS9039 is a very good source device for easier to drive iems, which is most iems. I don’t have any over-ear headphones to test either so please forgive me for that.

Battery Draw​

Another great feature is also not really a feature per se. That is… battery draw, or lack thereof. Like I said earlier the RS9039 does very well at not killing my phones battery. You see this very evident when you begin to compare the RS9039 with other dongle dacs of similar pricing. I’d say only the Simgot Dew4x, and the Hidizs S8 Pro Robin are the only two which seemed to get around the same battery draw. Now, I did not actually run any tests to see how long it takes the RS9039 to actually drain my battery. I simply pay attention and I’m always watching closely to the battery on my phone. Every time I’m ever listening to any dongle dac I do this. It’s embedded in me to do so and it’s plainly obvious that the RS9039 does better than most. Of course, you simply have to take my word for it in this one. I stand by it.

Sound Impressions​

Note: I should preface this entire section by letting you all know that I did let the RS9039 burn-in for roughly three to four days. I realize that this is a questionable action with questionable results, but I figured I’d get it out of the way anyways. I didn’t notice any real change, but that doesn’t mean there wasn’t any change either. It’s hard to remember (four days prior) exactly what you heard. For critical listening, I listen to flac or better files stored on my devices using the UAPP app (mostly) as well as Hiby Player. Also, I should state that source reviews are some of the more challenging to explain. I say this because most of the way the sound will be tailored comes from the earphones or headphones you have attached. All the sources can do is influence that sound. Of course, some devices will affect that influence greater than others.

What’s it sound like​

If there was one enduring quality that I noticed from the jump with the Roseselsa RS9039, is that it’s a warmer sound. Not only is it a warmer sound but it’s also a bass emphasized sound. Without question the RS9039 tweeters to the left. Why do the scales tip to the left? Because of that low-end emphasis in combination with the fact that the right side of that scale is less emphasized. The highs are less profuse, almost rolled-off in comparison to similarly priced done dacs. So, it’s warm, but along with that warmth is a smooth and richer note body throughout. This all equates to a sound that is generally characterized by “musicality”. Certainly, a more organic, natural, and earthy sounding dongle dac. To a degree. I’m not speaking in absolutes here. The truth is that the RS9039 is a very nice sounding warmer device that is fantastic for brighter iems if you seek to take the edge off a bit.

A warmer tilt​

To be perfectly honest, this slightly warmer tilt threw me for a loop folks. I was not expecting this ES9039Q2M Sabre dac chip to come across this way. Not that that’s a bad thing either. “Warm” and “rich” certainly have their perfect spot in the Audioverse. So, I was a bit surprised, but at the same time it was good to hear something different from neutral and analytical. Now, one downside is that detail retrieval won’t always be the best. Granted, if you have an analytical style iem, the RS9039 isn’t going to turn it into a veiled and mushy mess. No sir. The RS9039 will only give your listening experience a warm shade over your listening. Analytical sets like my Softears Studio 4 are still great for details. That said, sets like my Simgot EA1000 are much better at expressing the upper midrange without that glare that can occur from time to time. Is it world changing? Probably not.

Influence​

Source devices only really influence the sound to a degree, one way or the other based on which side of the scales they tip to. How much they can color the sound is how far from neutral they skew. They can enhance clarity a bit, add dynamics, add energy and increase control. Source devices can add depth to an extent and even layer the sound etc. They can add a sense of musicality or bring upon a more analytical flair to your earphones. Sources can truly make or break a listening experience. In the case of the RS9039, it influences the sound a bit richer, with a bit more of an earthy glaze. It’s a nice change of pace if I don’t say so myself. Let’s put it this way, the very warm and rich sound of the Penon Fan 2 doesn’t all of a sudden sound like a milkshake thick mess of mushiness. The sound is still clean, and the micro-dynamics are still present. There’s still some nice energy in macro-dynamics as well. Perhaps not that ultra energetic, brilliant, and sprightly sound, but it’s definitely not boring. I can certainly understand if there are those folks who don’t enjoy this type of sound as much, while at the same time the opposite of that is true too.

Beyond the tonality of the RS9039, I do like the highly resolving nature of this slightly warmer sound. This is not a gooey and veiled sound. Transients still sound tight within this smoother canvas. To the extent that they can be swift and tight. The sound is very clean and very transparent for what it is. The stage is very full in comparison to a few other dongle dacs and there seems to be some depth to the sound as well.

Bass Region​

The bass is full. I could stop right there, and you’d get the gist of it. However, we know me better than that. The bass has a definite density to it which can really add a new dimension to some iems in comparison to some other dongle dacs. For instance, listening with the Kiwi Ears Orchestra Lite I found the low-end to have more authority than with other dongles. The low-end seems to add a touch of punch and even some pointed impact but mostly the low end simply sounds fuller and more profuse in its quantity. No, the RS9039 will not turn your bass lite sets into Bass-Boi Baddies. However, that warmth that it provides will thicken up the sound altogether and will give a bit more grunt weight to the bass region notes. There is some very nice extension added to my iems which on some sets is exactly what I needed. Others could use a bit less too but that’s the hobby. It’s an ever-growing search for that perfect synergy.

Midrange​

The mids borrow some slight warmth from the bass region which provides a butterier sound with the right earphones. What I enjoy is that the RS9039 still has a certain level of transparency which is very nice to hear when coupled with the richer note density it can provide. The background is as black as can be (so far as I can tell), even with sensitive iems which ultimately seems to form a nicely contoured outline around midrange notes yet in a smoother delivery. They sound quite nice with the right set of iems. The mids are slightly more forward, good presence, but also less energetic as many other dongle dacs. It’s up to you if this is a good or a bad thing.

The right pairing​

Again, coupled with the right earphones you’ll be surprised just how clean a sound the RS9039 can provide. Listening with the Simgot EA1000 is a real treat. Take the highly resolving and completely vibrant sound of the EA1000 and the warm and lush influence of the RS9039 and you have yourself a great pairing. However, if you take the slightly warmer sound of the QOA Aviation and pair it with the RS9039, the sound may not be as vivacious as one would enjoy. On the flip side, I also don’t hear any extra upper-mid energy to wreak havoc on my eardrums. Detail retrieval may leave a bit to be desired with less transient swift iems as well. I found the Softears Studio 4 to be a very nice pairing however with nice detail retrieval and a very transparent sound. Still, compared against other dongle dacs I do feel the RS9039 isn’t quite as technically sound all the time. I the end I find the midrange to be nicely musical with an emotional tilt to my music. Never harsh, never grating, never sibilant and always a clean background.

Treble Region​

The treble region is not the most brilliant of treble displays. It’s somewhat laid-back and less enthusiastic, so to speak. There’s a slight feeling of roll-off when listening to the RS9039. I simply don’t hear that vibrant and shimmery energy up top. The RS9039 isn’t tuned in such a way to add more levity to my earphones, but instead they knock the edge off of some brighter sets to a slight degree. However, at the same time they also may come across a bit duller to some folks as well. That said, depending on the earphones/headphones you choose this can be a wonderful thing… or a no-go. This isn’t the most detailed presentation up top, and it isn’t the most extended either. The treble region of the Roseselsa RS9039 is non-offensive all the way through and like I said, it should subtly buff down some peaks. Simply put, there’s no extra treble energy and extension and what you are getting is a simple moderate emphasis. I wouldn’t call the treble dark, but I would probably call it warm I suppose. Great for those who are sensitive to upper mid pinna gain and heightened treble emphasis. I feel those folks are going to enjoy this device quite a bit.

Technicalities​

Technically the Roseselsa RS9039 is what it is. What is that? Well, the RS9039 is in my mind geared towards warm musicality and everything else is just icing on the cake. With a slightly thicker sound, less energetic, less expressive in the air regions and the treble in general which would otherwise add some luminance and help to bring out the subtleties in music. This is not the case… not always anyways. Detail retrieval is not going to get better on your iems or headphones with the RS9039… let’s just put it that way. It simply isn’t tuned in that way. Separation of elements on the stage are a little more constricted. Not to any detrimental degree either, but the sound isn’t that analytical, dry, airy, fine lined, neutral-clean, and ultra-resolving type of sound, and folks should be aware of that. Having said that, the RS9039 also isn’t deficient in these attributes either. It’s still pretty good and on top of that, it’s a musical, organic, and more earthy sound which has its own endearing qualities and charm.

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Comparisons ​

Moondrop Dawn 4.4 ($65)​

Oh, the Moondrop Dawn 4.4. I have used this little guy for a long-time folks. I really enjoy its sound and the way the Dawn controls the spectrum. It’s simply tuned very well. Now, the Dawn comes equipped with an older dual dac chips in the CS43131. However, just because something is older doesn’t make it worse. I never got around to reviewing the Dawn 4.4 but if I did, I would’ve called it one of the best pure music dongle dacs that money could buy when it was released. However, there are a number of issues which hold it back. Namely, no buttons and it only has a 4.4 balanced port rather than both a 3.5 single ended and 4.4/2.5. Most certainly this was an issue with prospective buyers.

Differences​

To start, the Dawn 4.4 is round in shape and so you should be aware that it will roll off a table if not tied down. Also, the Dawn 4.4 provides slightly less in output power with 240 mw @32 ohms to the RS9039’s 300 mw @ @32 ohms. To be honest, that’s so close you don’t even notice it. I did notice that the Dawn 4.4 can decide PCM @ 32bit/768khz to the RS9039’s 32bit/384khz. Both provide DSD256. Both are built very well, both made out of aluminum, however the RS9039 actually has a replaceable cable whereas the Dawn 4.4 only has a fitted cable. This never bothered me but if it breaks, the Dawn 4.4 will be inactive. The price on both devices is very close and so to find any differences you will have to look towards the sound department.

Sound Differences​

Both devices are very good at replaying music, yet both are tuned quite differently. The RS9039 is warmer, thicker, more robust. The Dawn 4.4 runs neutral, clean, punchy and well detailed. The low-end of the RS9039 is boosted substantially more, deeper and denser bass which influences the rest of the spectrum quite a bit more resulting in warmth and heavier, richer and more organic note weight. The Dawn 4.4 is snappy, crisp, crunchy in its treble bite and very resolving. The low-end of the Dawn 4.4 is nicely defined, carved edges, quick transients with clean lines and air between instruments. Truly these two could not be further away from each other sonically. The RS9039 has a milky midrange to the Dawn’s thinner but more transparent and cleaner midrange. Technically the Dawn is superior by a small margin while the RS9039 presents a more musical and more engaging sound. I find the stage is a bit wider in the RS9039 as well as a touch deeper while the Dawn 4.4 has that vivacious energy and vibrance that really brings some good macro-dynamics to my listening experience.

Final thoughts on this comparison​

Without question this comparison is the definition of a “preference battle”. These two are wholly opposite and each has its place among some of the best sound under $75. Each device replays music at a high level but yet in different ways.

Simgot Dew4x ($79)​

This is a special device folks. The Simgot Dew4x (Dew4x Review) came out recently and had its share of fanfare. I wouldn’t call it hyped, but folks really enjoyed it. I am one of those people. It houses brand new CS43198 dual dac chips which I have grown quite fond of. The Dew4x also comes equipped with about half the output power of the RS9039, but it does have volume buttons, gain buttons, track buttons and sound filters too. It’s built very well and is very light as well. Just a fine device that I really do enjoy.

Differences​

First off, the RS9039 is about $10 cheaper (give or take) depending on where you purchase from. It’s a hair smaller (lengthwise) and about the same weight. Both devices are built extremely well. Neither is going to fall apart anytime soon. These are two companies who pride themselves on build quality. Both devices have brand new dac chips from some of the best dac chip manufacturers (Cirrus Logic & ESS Technologies). Now, like I said, the Dew4x does have BUTTONS. We love buttons. Again, it has options to change sound filters, change volume, skip tracks, the whole nine yards. It simply lacks an app. However, the RS9039 has none of those unfortunately. Thankfully we don’t buy anything in this hobby solely based on buttons and features. They’re nice, but we care about sound.

Sound Differences​

I would characterize the Simgot Dew4x as warm/neutral with only the slightest tinge of warmth. The RS9039 is warmer than neutral (as you know). The bass of the RS9039 will actually add weight and density to the lower end of the spectrum. Bass will be added to, bigger, fuller. The Dew4x, with its CS43198 dac comes across less emphasized but more pointedly punchy. Snappier. Each device suits a slightly different earphone if you go by the logic of opposite pairings. Both are clean. This goes for the rest of the spectrum as well. The RS9039 has a heavier note weight, more organic, more musical and the Dew4x is better resolving, better detailed and better separated. The RS9039 is simply warmer across the board with a much less emphasized treble region in comparison. The Dew4x will bring an airier sound and has a better upper end extension. Technically the Dew4x is simply tuned to be better in this area. However, the soundstage of the RS9039 is a hint wider and slightly deeper too.

Final thoughts on this comparison​

Friends, the truth is that these two devices once again represent a true “preference battle”. Meaning, they both sit so far away from each other in sonic qualities that you’ll know right away which one you enjoy better. Before conducting comparisons, I knew I would have these types of comparisons. Where both devices emphasize almost opposite areas of the mix. However, both devices are actually pretty great. I use them both for different purposes. Thankfully, I enjoy damn near every sound signature out there which is very helpful for reviewing. That said, you will likely already know which is better for you. I don’t think either is a clear winner in any area. Unless of course features mean a tin to you, then the obvious choice is the Dew4x.

Is it worth the asking price? ​

Is the Roseselsa RS9039 worth the $69 that Rose Technics and HiFiGo is asking? This is a great question. It’s a nuanced answer too. Well at least to a degree it is. For me to answer this I’d have to take a couple different angles. For the person who loves a neutral sound that leans analytical and comes across vibrant with energy and expressiveness, they will likely not find the RS9039 worth the asking price. I’m sure those folks would have a multitude of devices which fit those criteria. Also, to those who simply need features and more control over their listening experience. Those folks probably don’t consider the RS9039 worth the asking price.

Unique​

However, this is a very unique tuning that you don’t hear much anymore. Rose Technics took a chance in how they went about tuning the RS9039. I say that because it isn’t everyday you present such a warm, moody, and melodious type sound. So, for those folks who love a slightly thicker sound, more emotionally gifted, or a sound that laughs at details and champions musicality and engagement. To those folks, I think I have the device for you.

The Why…​

From the perspective of the person who does enjoy a warmer, less offensive, less glaring and peaky sound and who enjoys a thicker bass. First off, the RS9039 is built like a champ and is slick looking as well. Beautiful lines in an aerodynamic style. Looking more like a sports car than a dongle dac. What a tough look and design. However, it’s the sound. The RS9039 has that profuse and almost bulbous low-end (especially when paired with a bassy set) that is nicely defined for what it is. This is a set that will give less bass inclined sets that last little bit of oomph and will calm down peaky sets to a degree. In general, this is a situational dongle dac that when paired right is a truly wonderful purchase. You have to know what you are getting though. I really feel that Rose Technics made a special source device that I’m very glad to have in my arsenal. Also, yes, it’s worth the $69 it takes to own it!

Conclusion​

To conclude my full written review of the Roseselsa RS9039, I first have to thank the good people of HiFiGo who provided this device to me. HiFiGo has been nothing short of awesome and the great contact with whom I deal with is always very helpful and never asks anything out of me except to review with honesty. Never have they asked to pre-read a review or rush me and that is very nice. I’d also like to thank anyone of you who chose to click the link and read this review. I and everyone from mobileaudiophile.com thanks you. Every click helps, the amount of time you stay helps too, so thank you very much and I do hope this review has helped you. That is the goal.

Other perspectives​

It wouldn’t be a Chris Love review if I didn’t plead with you all to check out other thoughts, other than mine. Folks, each and every reviewer on planet earth is different. No two of us are perfectly alike. We can hear different, like different styles of music, have different gear and not everyone of us has had the same experience within the hobby. Please look further into other thoughts and don’t simply read my review and hit “buy now” unless you know me and trust my thoughts. I know that $69 is a ton of money for most of the peoples of this world. Heck, $69 is a lot for me. Three kids are never cheap, and every dollar counts. Money doesn’t grow on trees; I get it friends. I don’t want to steer any of you wrong because a $69 purchase may be the only purchase you make for a long time. It has to be right. I say what I hear and hear what I say and nothing more. This I can promise. However, what I hear, the next guy may feel polar opposite about and guess what… both of us are correct. Beyond this, I think I’m done. Take good care and stay as safe as possible, and always… God Bless!

Review and comparison of Rose Technics Roseselsa RS9039

The Rose Technics Roseselsa RS9039, which costs $79.99 US, is a simple dongle DAC with no volume control buttons. As a result, you can only utilize your phone's volume controls. Personally, I don't mind because I solely use my phone's volume control, including on dongle DACs with volume control. Despite its simple form, it has the newest DAC chip from ESS Sabre, the ES9039Q2M, which I find pretty fascinating because I have dongle DACs with older ESS Sabre chip generations, so a sound comparison is a must.

It can drive average sensitivity IEMs to a high volume levels, but will struggle a little with difficult to drive sets and could get very warm, so I urge you to avoid difficult to drive sets with the Roseselsa. For this review and comparisons, I use my reference IEMs: The Dunu Falcon Ultra Ti and Xenns Mangird Top with the 4.4mm connection.


The tone is warm, which is surprising given that the dongle DAC uses an ESS Sabre chip, which is recognized for producing analytical, bright, and detailed sound. The bass is prodigious and massive; as long as you don't clip it, it sounds like the bass of some high-end DAPs or desktop setups; nonetheless, it can sound loose and out of control at times, especially on IEMs with planar drivers and other difficult-to-drive settings.

I don't have any issues with the midrange; it sounds as good as it can be, clean and transparent, but on the upper midrange and treble, it sounds a little laid back or polite. I don't know if this is inherent to this new chip or if it is the tuning and imprelementation by Rose Technics, but I suspect it's the latter.

The upper treble is very smooth, clean, and polished, more so than any of the dongle DACs included in the comparisons; it is not blunted, just laid back, and sounds very extended with plenty of micro details, but could sound less engaging compared to others due to its relaxed upper treble sound.



Rose Technics Roseselsa vs Kiwi Ears Allegro vs Hidizs S9 Pro Plus Martha.

Please note that this section is copied and pasted from my Kiwi Ears Allegro review.

They represent three generations of ESS Sabre chips: the Allegro has the ES9028Q2M, the oldest, the S9 Pro Plus Martha, has the ES9038Q2M, and the newly released Roseselsa has the latest chip, the ES9039Q2M. Let me warn you in advance that any sound differences I point out are, in reality, really small; most people might not notice them.

I did an extensive three-way comparison, and the first thing I noticed was that the Roseselsa was the bassiest, the Allegro was the most neutral in bass, and the Martha was the most bass-light of the bunch. The Roseselsa might be the bassiest, but the bass is less controlled than the bass on the Allegro and could sound boomy at times. The Martha also doesn't have the most controlled bass and could sound boomy at times. It also has the least bass of the three due to its slightly elevated upper mids and treble sound. Again, the differences are tiny, but for me, the Kiwi Ears Allegro wins in this round by a wide margin due to its excellent bass control, making the bass sound very textured and non-boomy.

I heard no discernible differences in the midrange, but at the upper midrange and treble, the Martha was the most forward-sounding, bringing the details closer, the Allegro was neutral, and the Roseselsa has the most polite sounding of the three. I prefer the Allegro and the Martha equally in this round, as they sound more musical for me, but don't get me wrong, they all sound great, and the differences are really small.

In the upper treble region, the Roseselsa was the most polished sounding, the cleanest sounding too, but it sounded a little polite; the Allegro is the least polished sounding; the Martha is in between; it has the best balance of smoothness and liveliness in the upper treble; and I prefer it over the other two, so the Martha is the clear winner for me in this round, but again, the differences are very small.

In terms of sound stage, the Roseselsa has the deepest, followed by the Martha, and lastly, the Allegro. The Roseselsa also has the cleanest and darkest background of the three. Roseselsa clearly wins in this regard.

Of course, the implementation and tuning of the DAC chip also play a role in the final sound quality of the dongle. Therefore, the differences between these three cannot be pinned down to the chip alone.


Pros:

- simple design and small in size
- affordably priced
- great value for money
- great sound
- Big bass
- smooth treble
- non-fatiguing sound

Cons:

- The lack of volume control could be an issue to some people.
- The warm tonality might annoy some people.

Conlusion:

It has the detail and resolution of which ESS Sabre DAC chips are known, but at a surprisingly smooth delivery. Add to that the affordable price, and you have a dongle DAC with great value for money, and thus, the Rose Technics Roseselsa RS9039 comes highly recommended.

Have a nice day! Cheers!

DISCLAIMER

I would like to thank Hifigo for providing this unit.

The ROSESELSA RS9039 can be gotten here: https://hifigo.com/products/roseselsa-rs9039 or https://www.amazon.com/dp/B0D3PWW3C3/roseselsa+rs9039/ (no affiliate links).




SPECIFICATIONS/COMPATIBILITY



Tested at: $75.99 USD

The RS9039 is a plug-and-play dongle. No additional driver installation is needed for Windows 10 and above, and this dongle was easily recognized by various Windows and Android devices I paired it with. As I am not an Apple ecosystem user, I can't vouch for its compatibility with this subset of products.


ACCESSORIES



Other than the dongle, the packaging comes with:
- Carrying case
- USB-C to USB-C cable

While there is a lack of a USB-A adapter and Lightning cable, at least Roseselsa has provided a huge carrying case. This is large enough to store the dongle plus accessories, and the externals are hard, with soft cushioned internals.



The USB-C to USB-C cable is on the shorter side, though it is well braided with reinforcement at the cable insertion areas.


DESIGN/FUNCTION



The RS9039 is fashioned from CNC-machined aluminum alloy. It is literally built like a tank, with a matte silvery finish. All the edges are smoothened, with no poking parts, so do not worry about being stabbed during usage!

Measuring 48 x 22 x 12 mm, and weighing a mere 14.5 g, this dongle is very light and compact, and can easily fit in a pants pocket.

The RS9039 is a no frills dongle, with no app compatibility and no PEQ options. Neither does it have any filters or screen, and - this may be a deal-breaker for some - it glaringly does not have any volume controller or gain options. Hence, users are stuck to adjusting the volume at the upstream source (eg DAP, phone, computer etc).



On one end, we have the USB-C port for power and data, and the opposite end contains the 3.5 mm (single-ended) and 4.4 mm (balanced) ports, with both reinforced by gold-plating.



INTERNALS

This DAC/AMP is powered by an ES9039Q2M saber chip. It allows playback of PCM up to 32bit/384kHz, and DSD up to DSD256.

The back of the dongle incorporates the design schema, for the technical junkies that are interested in the inner workings.




SOUND/PERFORMANCE

I tested the RS9039 with only Android phones and Windows laptops and PCs. Once again, I'm not an Apple user, so I can't confirm its performance with Apple products.

On phones, I used the HiBy Music Player, with USB bit perfect OTG activated on a Samsung S22.


Tonally, the RS9039 sports a warm neutral signature. Timbre sounds natural with a relatively clear midrange. End-to-end extension is good.

When discussing technicalities, the RS9039 has an expansive stage, with excellent imaging and layering. Micro-detailing is captured well, with solid instrument separation. Essentially, nothing sounds claustrophobic or compressed, and the keyword to describe the soundscape would be "grand".

Power-wise, this dongle is marketed to output 240 mW (@32 Ω) for the single-ended port, and 300 mW (@32 Ω) for the balanced one. While the RS9039 would be considered to have big juice on tap, it isn't the most powerful dongle in this sub-$100 USD bracket - that goes to the Fiio KA13 - but it should power most gear out there, other than outlier beasts. Sadly, there are no gain settings available.

As usual, I put all dongles through a series of acid tests in driving ability:
1) Final Audio E5000 (low sensitivity at 93 dB/mW)
2) Sennheiser HD650 (high impedance at 300 ohm)
3) Yinman 600 ohm (600 ohm impedance and 87 db/mW sensitivity)

On 4.4 mm, the E5000 was surprisingly driven well, with good bass texturing and speed, though soundstage was a tinge smaller than more powerful sources. The HD650 was amped solidly, soundstage and dynamics were not too far away from desktop type sources.

The final boss - the Yinman 600 ohm - which has a ridiculously low sensitivity coupled with high impedance, is not driven properly by the majority of portable devices. Headroom was reached adequately here, with surprisingly serviceable dynamics and soundstage, though bass was somewhat flabby. This is a commendable effort, as some pricier sources cannot drive the Yinmans to the same extent in terms of quality (not reaching the volume, but driving well).

This dongle gets warm but not hot even when paired with hard-to-drive behemoths. There is no hiss heard with sensitive IEMs. However, there was a minor "pop" heard on disconnecting IEMs. Some dongles have a worse "pop" suppression system, and this was just a small inconvenience noted here on the RS9039.

We have no information on the output impedance specs of this DAC/AMP, but I surmise that it should be relatively low, as fastidious low impedance IEMs that were paired with it sounded similar tonal-wise.


COMPARISONS

Comparisons will be made against other sub-$100 USD dongles.



Penon Tail

The Penon Tail uses dual CS43131 chips; it is also a barebones dongle in not having EQ, app, DAC filters, or a screen. However, the Tail does have a volume control, but this is not independent with wide steps between each level. Additionally, the Tail has no "pop" suppression installed, and the Tail fares much worse, with a way larger "pop" noted on removing IEMs.

The Tail is more neutral but with a thinner note weight and a more artificial timbre. The Tail's power specs are roughly half - 151.25 mW (at 32 ohms) on 4.4 mm - compared to the 300 mW on offer with the RS9039. As such, the Tail cannot drive too demanding gear.

The Tail falls behind in technical pefrormance, espousing weaker soundstage and imaging.


Fiio KA13

The KA13 is a neutral bright dongle with dual CS43131 DAC engines. It is brighter, with potentially more sibilance in the higher-end. The KA13 is also more metallic, and doesn't sound as full in tone.

The KA13 on 4.4 mm desktop mode can hit 550 mW output (THD+N balanced＜0.0005% (32 Ω)), trumping the 300 mW available on the RS9039. Hence, the KA13 can potentially juice more demanding outliers, though we can't game physics as the KA13 gets hotter during use, with more battery drainage.

In technicalities, the KA13 is inferior in soundstage and imaging.

However, the KA13 has more UI goodies to play with - it has a Fiio control app for settings configuration, in addition to having a well-implemented independent volume control with finely tuned steps.



CONCLUSIONS

The Roseselsa RS9039 is a unique of flower within the dongle greenhouse ecosystem. It is a source designed splendidly when it comes to music appreciation - there is huge power available to drive most gear - coupled with excellent technicalities, housed within a warm neutral signature. Soundstage and imaging are a highlight, and it sounds "grand". On A/B comparisons against other dongle rivals, these other contenders sound compressed in contrast.

However, some consumers might find the RS9039's UI to be sorely lacking, with no app, PEQ, filters, nor screen. It does not even have a volume controller or gain options, which is a admittedly a potential deal-breaker! It seems that Roseselsa has concentrated most of their efforts into the tuning and music playback, but the rest of the bells-and-whistles of a modern day dongle are somewhat undercooked, so to speak.

Thankfully, the RS9039 is built like a tank, with a compact and portable frame, and it comes with a big carrying case. The RS9039 does not heat up drastically during usage too. Though there is a bit of a "pop" noted on disconnecting transducers, there are other dongles that do much worse in this arena.

All things considered, this DAC/AMP is one for the true audiophile connoisseur: someone that focuses purely on the music and wants superb sonic reproduction, without caring about external aspects like volume controls or filters or PEQ. In all likelihood, if you are reading this, you probably fall in the former camp of wanting the best-sounding dongle at sub-$100 USD, and this might hit the spot. For lay-consumers that want something more friendly in terms of value-added functions, there are other dongles to consider, though with perhaps compromises in technicalities or tonality.