Reviews by alamnp

Technical Specification:

Configuration: 13.6mm single graphene diaphragm dynamic driver
Frequency response range: 20Hz-40KHz
Sensitivity: 102 dB
Impedance: 18 ohm
Color: black

Packaging:

The packaging is definitely eye catching, retro and looks super cool. Packaging definitely above average compared to its peer.
What is included in the box:
- The OS 1 Pro IEM
- 2 pins detachable cable
- 6 silicone ear tips S,M,L
- warranty card
- product information card

Design and Fit:
I got to give Opera Factory two thumbs up for its design and fit. Even though it has a plastic casing, but it is designed artistically, does not look like a $20 IEM at all. It is also small in size, which probably good for most people, because it fits like a glove inside my ear without any problems. Tips rolling is not needed in this case, the silicone tips included with the OS1 is perfectly positioned OS1 inside my ear canal and achieve optimal seal.

Sound and Pairing:
For the purpose of this review I pair OS1 with my BTR5, using the stock cable included with the IEM and also using 2.5mm Silver plated cable from KBEAR to benefit for increase amplification with 2.5mm pin. I also tried it with Iphone XR, which I thought it did not do justice for this IEM.

OS1 paired with BTR5 with stock cable:
I am surprised with the detailed mid bass here, it's punchy without bleed into the mid, rare for a $20 IEM. I tried so many songs from my Tidal collections and I found that OS1 did really well with female vocal, especially the ones that borderline sibilant. It made the female vocal up, close and personal with seductive tonality. However, it did not do good with male vocal, it made the male vocal sounded a bit distant and thin.

Due to rolled off treble, it made OS1 a warm IEM, fun and easy to listen. However, if you are a treble head, I would suggest to look elsewhere because this is not your IEM.

Sound stage is about average, but it does not sound congested. Clarity suffered a bit with low powered source (Iphone XR), but not with BTR5. Imaging and timbre also average, but comparable to TFZ Live 1 which cost more than this IEM.

I also changed the cable with 2.5mm pin KBEAR silver cable to take advantage of 240mW (120mW per channel) output from my BTR5 which improved the overall sound stage and clarity by alot.

Verdict:
There is no good bass head IEM under $25, if you are on a budget, this is definitely a bass head IEM for you, it is a no brainer. If you like to listen to KPOP female genre, this is also definitely your IEM, it makes me addicted listening to them (yes, even the ones that I could not tolerate due to borderline sibilant). On the down side you may need amplification to improve clarity, imaging, and sound stage; to bring this little baby to shine.

KB Ear Believe is the first beryllium DD ever sold below $200. I was really skeptical towards Believe initially. I was not expecting much because I already have a bunch of low tiered and mid tiered Chifi, and they don't differ that much from one another, probably about 5%.

I wanted to confirm it that it's not just the hype, so I jumped the gun on Thanksgiving getting my very first Beryllium driver from KB Ear.

I received my KB Ear two weeks ago and unboxing KB Ear Believe was just quite an experience.

KB Ear Believe comes in Aluminum 5-axis CNC casing with 3D plate at the back that looks very nice. It is smaller than typical IEMs, as a matter a fact KB Ear Believe probably one of the smallest IEM that I have.

KB Ear comes with plentiful accessories, 3 silicone tips regular bore, 3 silicone tips wide bore (Standard), 2 memory foam ear tip, upgraded Copper Silver plated cable 2pin 0.78mm - 3.5mm jack, and a really nice leather pouch.

I love the industrial all metal design with 3D back plate and I consider KB Ear Believe as very cool and good looking pair of IEM’s.

Ok, before we move forward to the essence of this review, to be fair, I did my 100 hours burn in for my KB Ear Believe. I also purchased KB Ear balanced Copper Silver plated cable with 2.5mm jack. Word of caution, KB Ear Believe NEEDS a lot of power, so please get yourself a DAC/DAP to extract its full potential. If you are going to just plug this to a phone or Iphone, I would suggest don't even bother getting Believe. It does have low impedance of 17 Ohm; however it also has lower Sensitivity than most IEMs at 98dB. With my Iphone X, max volume only yield about 60dB of sound.

With 2.5mm jack balanced cable you get extra boost about 10dB, however I don't really need 2.5mm jack balanced cable, with the 3.5mm jack unbalanced cable I don't have to max out my BTR5 with Believe, at 50% there is plenty to hear.

For the purpose of this review, I will be pairing KB Ear Believe with my FIIO BTR5 DAC.

Fit:
KB Ear out of the box fit likes a glove to my ear canal. I don't even have to do tip rolling. It provided me with great seal to start with, probably due to its small size.

Sound:
The overall sound of KB Ear Believe is perceived as neutral balanced with enhanced the upper mid range that gives great detail retrieval and crystal clear treble without sibilant. I am so surprised that Believe can walk that thin line of being sibilant and not, and able to maintain that crystal clear clarity without being too brilliance. I don't really understand this, but this makes Believe as an exceptional IEM. Out of the box, the sub bass and mid bass were fast and detailed without bleeding over to the mid range. Initially, I did not like the bass because even though it was detailed enough, but it's lacking in punch. However, it changed after 100 hours burn in, the bass really hits it when the song requires it. Sound stage also improved after 100 hours burn in, it is wider, taller and deeper with great separation. I usually do not enjoy Coldplay songs on other IEMs because they sounded congested, but OH BOY!!!, not with Believe, I was so surprised how Believe can handle complicated track accordingly, providing much details, accuracy and precision on percussion. To me, it's just heavenly. Instrument placement and separation on Believe, I think is the best compared to any other single DD within its price range.

Comparison vs NM2+:
NM2+ is a lot bigger than Believe, fit and seal is better with Believe than NM2+
The bass out of the box, probably NM2+ is better; however its mid bass do bleed out to the mid range giving that warmth overall feeling compared to Believe clear clarity full bodied overall feeling. The mid range, no doubt Believe has a clear edge against NM2+, Believe has clear and precise mid range without mid bass bleed, male vocal more full bodied and female vocal more intimate and seductive in my opinion (I listened to Halsey and Blackpink songs alot). NM2+ has a tendency for distortion an higher volume, not sure making the Treble diminished especially with Bass ear tips provided by them. With Believe, the treble is spot on, plenty of extension, BRILLIANCE and yet not sibilant.

I want to thank KB Ear in creating this exceptional IEMs for me to enjoy.
Thank you.

General Information
New multi driver hybrid by TRN

Specifications:
Driver type: 1 Dynamic Driver + 5 Balanced Armatures
Impedance: 22Ω
Earphone sensitivity: 108dB/mW
Frequency range: 20 - 20000Hz
Cable Type: 2 pin 0.75mm
Weight: 30g

BEGINNINGS

This was my first TRN to date, I bought this along with my BT20S Pro to use on my other IEMs. I was going to try TRN previously, but always balked at the last moment due to horrifying rumors of poor Quality Control (QC). I bit the bullet getting this because I also had to get BT20S Pro Bluetooth receiver, so why not.

Unfortunately, my journey with TRN began with a sour start. I got first my BT20S Pro which I liked it out of the box, without problems. And I thought, I also might get lucky with V90S IEM, but BOY, I was wrong.

V90S came with just a generic small box, like my CCA CA16. I was not expecting much from TRN in terms of accessories, who did anyway with budget Chifi IEM sub $50 right, so my expectation are already quite low.

However, TRN still managed to disappoint me.

Right out of the box, the right ear monitor's sound fading in/out and died completely after 30 minutes.

I thought, it could be a faulty cable then I tried the pure silver cable that I also purchased from TRN, it did not work. I sent a quick note to TRN store @ Aliexpress for possible replacement and they were pretty slow and not responsive.

I was not happy about that.

Then I remembered that previously TRN had moisture issue, so I left my IEM out near my fan for a whole day. The following day, I tried it again, it worked, but not sure why the sounds so thin like a thin can that I was ready to send it back for replacement or complete refund.

But I did not give up yet since I did not really like the hassle of returning them back to TRN to get a replacement. So, I hooked my V90S nonstop to my media player for 8 hours without listening to it.

After 8 hours, not sure why the real sounding of V90S emerged.

SOUND

Isolation on the V90S is very poor. Due to its small body, short nozzle and LACK of good tips selection to secure the IEM, it is very hard to achieve good seal and placement securely. After muscling around with different tips, finally I got a good comfortable seal with Comply tip as pictured.

Comply foam tips were not really my first choice, but that's the only tip that could provide a good seal and secure the IEM inside my ear.

I tried Spinfit tips, Spiral Dot tips, KZ stock tips, none can secure it accordingly with a perfect seal.

TREBLE

The treble here with Comply foam tips sounded relax, not sibilant. V90S is definitely not for treble head. If you have tried CCA CA16 previously, its treble is similar to CCA CA16. However, it could also because I used Comply foam tips that would dampen treble more.

MID

Mids were recessed by a lot, I was taken aback by this. Vocals sounded thin. Also, it had annoyingly unnatural plasticky timbre. I had to EQ this accordingly, otherwise it did not sound that good. Maybe I got used to ZAX and CA16 sound profiles, that I found V90S' mids are annoyingly sub par.

BASS

Surprisingly, V90S had a balanced mid and sub bass.It was perfect for listening to hip hop music. Good texturing of bass, with good overall decay.

SOUND STAGE AND IMAGING

This where V90S was definitely lacking, although it was a fun IEM to listen to for Hip Hop.

Technicalities, imaging and sound staging is very poor. Sound stage is lacking in depth and width. And each musical instrument clarity and placement was nowhere to be found, it felt so cramped.

Now, if you don't believe me, try and listen to this song with V90S:



Now, after you listen to that song, tell me if you can discern the sound of "tsugaru shamisen - the japanese siter" in the background and the flute position. You will not be able to tell. Now if you, listen via ZAX or CA16, there is a clear separation between the two and correct placement of the two.

COMPARED TO ZS10 PRO (the same class)

Comparing to ZS10 Pro, fit wise, ZS10 Pro is much better.

Here, V90S wins in term of Bass (or maybe because V90S' mids are taking a back seat, bass sounds more accurate), ZS10 Pro has some bass bleed into the mid.

ZS10 Pro discernible mids totally triumphed recessed mids in V90S

Treble also much better on ZS10 Pro making it to have better clarity and sound staging than V90S.

No, you can't compare it with KZ ZAX or CCA CA16, definitely not in the same class.