StereoPravda SPearphone SB-3.5 RU Review

Like with the original 3.5, the dynamics are excellent and the detail retrieval for a 4-driver unit is remarkable. No matter what source the SB-3.5 is hooked up to, it always sounds very energetic and lively but the SB-3.5 RU is never overdoing it. Of course you get the typical nice black background we know from Balanced Armature designs and the SB3.5 RU adds great speed and PRaT to that.

The SB3.5 RU is very refined. As said, the energy level at all times is high, some may describe the RU as being more aggressive or shouty in the higher mids and treble region. If you like a smoother, darker and slower kind out of sound, this is the very opposite.

The sound stage width is really good as well as the spaciousness and separation. The sound stage still is wider as it is deep. The layering in the RU version is also quite good, something I didn’t always found to be the case with the regular 3.5.

The precision of the SB3.5 RU is impressive and because of the excellent clarity and cleanness every detail is extremely evident and audible. The SB3.5 RU’s note extension is impressive and its timbre is rich, engaging and addictive. This especially is the case in the upper bass and low mid to mid mid frequencies, though there seriously isn’t anything to complain about in the other regions.

The presentation from bass to treble has just the right amount of body and air, making everything sound very realistic and natural. By using a fuller/heavier amp or source you can change the fulness and impact of the SB-3.5 RU’s sound. (if you would feel the need to change it.) Personally I don’t really feel the need to change its character as I like to hear and experience how the designer intended it to sound.

The SPearphone SB-3.5 RU doesn’t struggle with anything or any kind of music, it’s always perfectly in control and doing what it does best: impress with its technical qualities, energy and speed.

If you are listening to the SB3.5 (RU) and you find it to sound light, bodyless, sharp or flat, you 99% of the time will not have a good fit. I know I keep focusing on this, but it’s really hyper important to get the fit right with this IEM design. After a few hours with a SPearphone IEM, you will immediately know what a good fit is and how that makes the IEM sound. Once you know that, it’s easy to readjust the IEM when you’re listening to it (and I do this all of the time). Don’t judge the SPearphones based on a 5m demo, but spend a few hours with it, perfecting the fit and you will be super impressed with what these IEMs can do. With the RU version, getting the fit right is perhaps the most difficult of all, but it’s really worth it.


The amount of bass and the impact you get with the SPearphone SB-3.5 RU does depends on the source you’re using it with but in general you get a normal and natural presence. As with most higher end IEMs, the quality is more important than the quantity. Bass is balanced and always tight and fast. The limited number of balanced armatures don’t deliver the kind of bass that will shake your brain, but it certainly isn’t bass light either. There actually even is a nice amount of sub rumble.

The bass tonality, detail and layering are nice and – as said – bass does reach down to the sub levels. However, you shouldn’t expect a sub presence like in the U18s in example. If you’re a bass head, the SB-3.5 RU will not be your thing. If naturalness, precision and neutrality are your thing, the RU’s bass section will impress you.


The RU’s mids are natural, spacious and they have such an enjoyable timbre. Note extension here is excellent and you get great speed and detail with good separation and spaciousness. The mids are musical, energetic and rich in detail (not warmth) and give you a natural, transparent, clean sound. The level of clarity is impressive. The vocals are powerful yet realistic and natural. The most impressive for me in the mid section are the timbre, naturalness and extension.

Like with the bass the mids in general aren’t the fullest or heaviest but it depends on the source used. The mids are neutral in presence and they body, presence and impact-wise perfectly connect to the bass. The upper mids carry the most energy and that connects them to the energetic treble section.


Treble is highly energetic as well as extended and it has really good detail (though the quality of your source will certainly have an impact on this). Misha tuned the treble in a way that it’s very energetic but it never becomes harsh, aggressive or sibilant to my ears. Younger ears or aficionados of softer presentations might find the RU sounding extreme already though. You however do get great clarity and transparency and the treble flows perfectly from the energetic upper mids section.

If you like easier on the ear, soft and rolled off treble then this isn’t the treble presentation for you. Treble here is precise, extended and oh so present/energetic.

The overall treble tone is very energetic, precise and “high end”.

tereoPravda SPearphone SB-3.5 RU

Sound Conclusion

The more and longer you listen to the SPearphone SB-3.5 RU, the more you will fall in love with it as you will discover just how good and special it sounds. The energy level is high on this one, especially in the upper mids and treble section. Fit is crucial but get it right and you will be impressed by the RU’s high technical performance, its naturalness but also its musicality.

Vs the original SB-3.5

The original SPearphone SB-3.5 is a lot easier to listen to in regards to fit and comfort as it is a bit longer and smaller to fit into your ear canals.

Sound-wise the original SB-3.5 sounds a bit fuller but mostly softer and smoother. It has a bit more mid warmth compared to the RU but it’s mostly the energy here which is at a much lower level. Compared to the original, the RU sounds more aggressive, shoutier and energetic with a focus on the upper mids and treble section.

If you like a softer, more easygoing sound signature, the original SB-3.5 is your best friend. If you want a slightly lighter presentation, more excitement and energy with livelier upper mids and treble, the RU version will suit you more.

I can appreciate both SB-3.5 versions depending on the music I am listening to. If I could choose only one of both, it for my ears would be the original SB-3.5, simply because it’s softer on the ears for longer listening sessions (lower listening fatigue)

Vs SB-7

Like with the original SB-3.5, you can hear the same house signature in all models but in reality the technical performance and musicality level of the SPearphone SB-7 is quite a bit higher.

The SB-7 sounds more extended, wide and spacious and it doesn’t stop there as the depth, layering and decay are also ahead of the SB-3.5 series. I have to admit that the SB-7 is one of the very best IEMs when it comes to this, so it no shame that the SB-3.5 (RU) can’t produce the same level. The SB-7 just is a master when it comes to imaging, spaciousness, dynamics and the beforementioned characteristics.

The original SB-3.5 is more a mini SB-7 than the RU version is and that’s mostly because of the RU’s more aggressive/energetic upper mid and treble presentation.  The SB-3.5 and SB-7 have a smoother and less energetic delivery, and the latter really is what sets the RU version apart

If you’re already set at buying one of these unique IEMs and you don’t have a budget limitation,  then go for the best of the best, the SB-7. The SB-7 won an award after we reviewed it and it is still on our recommended list where it will be staying for quite a bit longer. If you’re set on getting a SPearphone but the SB-7 is out of your reach and you’re a fan of a highly energetic upper mid and treble presentation, than the RU version is an interesting IEM to look at.


Listening to the StereoPravda SB IEMs is always an experience. They are a one of a kind creation by a unique designer. You like them or you don’t

Sound wise the SPearphone SB-3.5 RU has a neutral sound signature and the technical level it performs at is high, but not as high as its big brother’s. With a good source the SB-3.5 RU will sound really good but it will always be highly energetic in the upper mid and treble region. The clarity and precision is exemplary, but it also means that smoothness and warmth are not ways to describe the SB-3.5 RU.

The StereoPravda SB-3.5 RU like its brothers will never win a beauty contest or get an award for comfort but the SB-3.5 RU isn’t about that. Misha’s “No pain, no Gain” philosophy is what it is but if you can handle that you can be sure to get a very nice and unique high-end sounding IEM with a sound signature you’ve never heard before. A fine example of a technical masterpiece.


Page 1: StereoPravda, SPearphone, Pain, SB-3.5

Page 2: Cable, Tips, Price, Packaging, Build Quality, Usage, Sources, Sound Pt. 1

Page 3: Sound Pt. 2, Comparisons, Conclusion

4.7/5 - (23 votes)


Lieven is living in Europe and he's the leader of the gang. He's running Headfonia as a side project next to his full time day job in Digital Marketing & Consultancy. He's a big fan of tube amps and custom inear monitors and has published hundreds of product reviews over the years.

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