Despite the fact that Penta is 5-driver hybrid, it has a unique tuning that could be compared to other 5-driver hybrids, or 5, 8, or 10 driver multi-BAs which I’m going to cover in the comparison below. In every case I was using LPGT as my reference source, Meze SPC cable with 4.4mm termination and adapters (if necessary) to match other IEM; also, volume matched in every comparison.
RAI Penta vs Campfire Audio Andromeda – the soundstage expansion in this comparison also has a lot of similarities, with depth being more out of your head while Penta’s width is just a touch wider. Unlike the previous comparison with A91, compared to Andro I hear the same bass quantity, but not the same quality where Penta’s bass is more articulate, having a little faster attack and shorter decay, giving it more control in comparison to Andro. But in general, the bass difference is not necessary night’n’day. Upper mids and treble is where I hear more difference. Again, with a focus around 2k peak which gives upper mids/vocals more crunch and clarity, Penta is more elevated and more forward, while Andro is pushed back and smoother and more laidback. But it reverses when it comes to treble where Andro is brighter and sometimes could get a little harsher in lower treble and has more airiness and more sparkle in upper treble, while Penta is noticeable smoother and more natural around the same peaks. As a result, Andro has a fun tuned signature with more focus around low end and treble, while Penta is more balanced and more naturally and evenly tuned.
RAI Penta vs Westone W80 – this is another very interesting comparison, despite that I’m stepping up to 8-driver multi-BA. Here, the soundstage in both width and depth are very similar. With bass, like in Andro comparison, quantity is very similar, but when it comes to quality the Penta has a faster/shorter attack and decay, giving its bass a better articulation. Treble is also nearly the same, well defined and still quite natural and non-harsh. Mids is where you will hear the biggest difference. Lower mids have a little more body in W80, giving the sound more thickness. Upper mids, especially around that 2k peak, is where you have the biggest difference where Penta has more forward presentation and vocals with more clarity, while W80 has its vocals more laid back, smoother, more organic.
RAI Penta vs Fidue Sirius A91 – the soundstage expansion in this comparison is close, with both having a similar depth with out-of-your head sound placement, but Penta has just a touch more width. The bass of A91 has a little more quantity, while the quality of the bass extension and impact and the balance between sub-bass and mid-bass are similar. Mids is where I hear more difference, especially in upper mids. Both have a natural neutral lower mids, and both have a similar peak around 2k, but Penta has this peak higher, making upper mids and vocals a little brighter and more revealing, with a slightly more forward presentation, while A91 has upper mids smoother, more organic, and slightly pushed back especially since A91 has a little more bass. The same with lower treble where 7k peak of Penta is a little higher than A91, giving the sound slightly more crunch. You can’t help but notice similarities in these two IEMs, but even with their more subtle sound difference, I hear A91 being smoother, warmer, and a little more relaxed, while Penta is more transparent, more revealing, and overall having a little more balanced signature.
RAI Penta vs EarSonics Grace – it has been awhile since I used Grace in my testing, but once I started listening to Penta, I felt it would be an interesting comparison. With soundstage, Penta has advantage of more width, while the depth is similar. When it comes to bass, Grace sub-bass extension and mid-bass slam is overwhelming more powerful than of Penta. Penta’s bass is elevated for sure above neutral, but Grace bass hits closer to basshead level, shifting its sound sig even more toward L-shaped. As a result of this difference, Grace mids/vocals are not as forward and not as balanced when transitioning from low end to mids. Penta mids/vocals have a better balance and a little more clarity, but most of it due to bass being less overwhelming when compared to Grace. Treble is very similar, just with Grace having a little more sparkle, while Penta having a little smoother definition.
RAI Penta has an average impedance (20 ohm) and a little higher sensitivity (110dB), still quite efficient and easy to drive from any portable source I tried it with. Also, I didn’t hear any hissing in the pair up examples I tried.
Lotoo LPGT – very wide soundstage expansion; balanced sound signature with a natural detailed tonality. Average speed, above neutral bass impact, natural detailed mids/vocals, well defined natural treble. This pair up probably exhibits the most balanced signature since bass impact is not as lifted.
Cayin N6ii w/E01 (Mode AB) – very wide soundstage expansion; balanced sound signature with a natural detailed tonality. The bass has a faster attack and more articulate punch, mids/vocals sound very natural and still quite detailed, and treble has a little more sparkle and airiness. Very good pair up which scales up the bass performance of Penta.
iBasso DX160 – very wide soundstage expansion; balanced sound signature with a natural detailed tonality. Average speed, above neutral bass impact, natural detailed more organic mids/vocals, and well-defined natural treble. Quite a balanced pair up here as well.
A&K SP1000 SS – wide soundstage expansion; balanced sound signature with a natural detailed tonality. While with some other sources the bass goes deeper (more sub-bass rumble), here I actually hear stronger mid-bass punch. Mids/vocals sound smooth and natural, a little more laid back. Treble is also a little smoother in this pair up.
Shanling M0 – wide soundstage expansion; balanced sound signature with a natural detailed tonality. The bass is a little deeper in this pair up, average speed, more typical of DD performance, mids/vocals are smooth, laidback, detailed. Treble is smooth, and still well defined. This pair up sounds a little smoother and warmer, with deeper bass impact.
FiiO M11 Pro – very wide soundstage expansion; balanced sound signature with a natural and slightly more revealing tonality. Bass here is faster and more articulate, with a performance which feels closer to BA rather than DD. Mids/vocals are still natural and detailed, but they do sound a little more revealing, slightly brighter. Treble also has a little more sparkle. Overall, this pair sounds a little more revealing.
Samsung Galaxy S9 (w/HibyMusic) – the soundstage is above average, but not as wide as with some other DAPs. Tonality is smoother, a little less resolving, while the signature is still quite balanced. The bass does have a little more impact (more lift), mids/vocals are warmer, while treble is still well defined and natural.
For those who are interested, here are a few comparisons to other cables I tried with RAI Penta. Majority of my cables are 2pin, thus I don’t have a big selection of MMCX cables.
Stock SPC to ALO Super Litz SPC – nearly the same performance, with an exception of ALO cable being just a little bit brighter. But other than that, nearly identical performance.
Stock SPC to DITA Oslo – also, nearly the same performance, but DITA cable is also a little brighter, especially in upper mids/lower treble. Surprisingly, it was even brighter than ALO cable.
Stock SPC vs Linum SuperBaX – this is first cable comparison which I actually liked over the stock cable. Perhaps due to a very low impedance of SuperBaX cable, the changes are more pronounced with a tighter faster more articulate bass and still natural but a little more revealing mids/vocals and a bit more sparkle in treble.
It’s always a bonus to have a combination of beauty and brain, and that’s how I felt about RAI Penta. Of course, a beauty is in the eye of the beholder and the brain, which in this case the sound tuning, is subjective and depends on your preference. But you can’t deny, these are beautifully crafted IEMs with a natural detailed full-bodied sound tuning. To my surprise, I read a few polarizing impressions either praising or criticizing their tuning. If you want a big bass slam or extra revealing crisp treble details, the tuning of RAI Penta not going to fit your sound preference. Instead, RAI Penta has a more relaxed, more laidback sound presentation with natural detailed tonality and a balanced sound signature. I found Penta’s to sound great with any genre of music I threw at them, and personally I enjoyed their non-fatigue sound tuning over extended listening sessions.