The Penon Rhodium-plated Modular Plug


Headphoneus Supremus
The Penon Rhodium Plug
Pros: 1) A quick and easy way to slightly alter your preferred DAP/Cable/IEM sound

2) Ever so slightly alters the response from your 3-in1 Penon/ISN cable

3) Reduces low frequency intensity and stance in the stage

4) Will thin-out a middle thicker response adding pace and trimming any slight warmth which can result in clarity

5) Adds brightness into higher frequencies

Compatible Models:
PENON 3-in-1 cables:
Penon OBSIDIAN, Penon Mix, Penon Storm, Penon Impact Cable, Penon Space, Penon Totem, Penon Leo Plus

ISN 3-in-1 cables:
ISN Solar, ISN H2, ISN S2, ISN C2
Cons: None
The Penon Rhodium Plug
As far as new cable choices, there are quite a few choices. But what if you didn’t need to buy a whole new cable for your IEM, what if sonic success was reached simply by adding a plug? Such choices are offered with a number of Penon/ISN cables. As such just $29.00 allows a change to your already in-place cable set-up.


Below showing the Penon 10th Anniversary IEM Model and aftermarket ISN CS02 Rhodium Plated Plug Cable.


I believe in cable changes, but often they don’t work miracles. Meaning if you have a favorite IEM in use and say you want to enhance an aspect of playback at times you can, but other times things remain the same........even with a different cable. Take for example the Penon 10th Anniversary Commemorative IEM, as my favorite Penon product ever. I love it…….but as always it’s not perfect. Nope, as an example…… playback vocals are good, but not the 10th’s speciality. So being what the 10th Anniversary is, I love it anyway, despite how it sounds, and maybe because of how it sounds in total? I mean I was the guy with the giant instrumental music collection, as sure some vocal music made it in, but as a whole I’m all about the instruments, not vocal replay. Now this doest mean the 10th’s vocals are bad....…, just not in emphasis. What would happen if we choose a permanent Rhodium Plated Plug Cable to use with the 10th? In comes the ISN CS02 cable, a legendary cable with the 10th. And while it totally changes so many attributes of playback, making the 10th the best I ever heard it, the CS02 cable doesn’t perform miracles, as vocals are different, but still not emphasized. But what the CS02 cable does is tighten up the bass, focus bass imaging, expand the stage in every direction and create enhanced imaging, even midrange imaging!

But what if we simply take off the Rhodium Plug from the CS02 and make it available to the public?

The Penon Rhodium Plug:

Top to bottom:
Penon Rhodium 3-in-1 Plug $29.00
ISN CS02 with Rhodium Plug $69.90

Penon OSG with Rhodium Plug $299.00

3 in 1 Series:
Penon OBSIDIAN $149.00
Penon Leo Plus $249.00
Penon Mix (with 3-in-1 Palladium "Purple" Plug) $149.00 (Cable by itself)

Penon Space $99.90

Each style of cable produces alternate sonic properties. But what if you could buy a single $29.00 (additive plug) to enhance an IEM/Cable set-up you already have in place?

That's what the $29.00 Penon Rhodium Plug is about.
That's what the $29.00 Penon Palladium "Purple" Plug is about.

Compatible Models:

PENON 3-in-1 cables:
Penon OBSIDIAN, Penon Mix, Penon Storm, Penon Impact Cable, Penon Space, Penon Totem, Penon Leo Plus.

ISN 3-in-1 cables:
ISN Solar, ISN H2, ISN S2, ISN C2

Interestingly part of this review is going to be the differences from the Purple Palladium Plug to the Rhodium Plug: Sure they both cost exactly the same and go into use much of the same way. But remember you're not going to normally be able to use these plugs on non-Penon cables. I tried and the pins don’t line-up. But as you can see if you already have the OBSIDIAN, Mix, Storm, Impact, Space or Leo Plus you’re in luck. They also work with the ISN Solar, H2, S2 and C2 3-in-1 cables.


For fun let's get started with the HISENIOR OKAVANGO!
One reason I picked this IEM is because of one price. The OKAVANGO comes in at $299.00 as a great example of what is possible in 2023 in IEM sound playback. Due to an affordable price it may be more in use than a flagship IEM. But the other reason is I found it incredibly balanced, almost totally even in replay. I mean the vocals were accounted for, the treble was nice, but not over emphasized, and the bass, while firm, was not over stated but just right. But like the Penon 10th, I was wondering if any enhancement was possible. Different from the 10th, the HISENIOR OKAVANGO has a slightly smaller stage yet once you start in a listening session none of that matters, except I wanted to see if I could enhance the stage, I wanted to open-it-up slightly. Also I was curious about imaging and definition? Also keep in mind that as far as IEMs go the HISENIOR OKAVANGO has a lot of leeway to move in a number of directions. You can make it brighter and it’s not too bright, you can add warmth and it’s not dull, and it would be fun to see if an increase in stage would bring about a larger style of playback. So what did I choose?

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The Penon Mix Cable:
The fact is once in a while the Mix (with its pure silver additive) is too bright. But yet somehow we reached a nice balance with the HISENIOR OKAVANGO. So lets change some plugs, shall we.


The included regular Copper Plug:
Probably the most relaxed replay, offering slightly warmer (thicker) itemizations into a denser stage. And while there could be finite separations and spatialization present with both the Palladium and Rhodium…….they were not necessarily always better but always definitely different…..depending on what you want. Meaning there was an increase in energy seemingly found with the Rhodium and Palladium Plugs, a focus of itemizations further from the backdrop………..normally found. Of course all this plays on the fact that system-synergy is always looked for, the combination of everything as one. Meaning yes, the HISENIOR OKAVANGO is well rounded and very competent to reveal such changes, but there could be further truths found with other even more detailed IEMs? And….again keep in mind it’s the full resulting combination of DAP personality, cable personality and IEM personality, to where there could be an attribute of only a single totally noticeable aspect which in-turn seals the deal? Plus not to mention the slight plug character, while the least dramatic effect on replay, is still a fact of life.

Meaning just ear-tip choices are going to make a noticeable and huge difference in playback, and while some neophytes may rely on the eat-tips single power to change sound, many of us have progressed onto other extra sound changing factors. What I’m saying is yes, ear-tips cause a dramatic change of audio circumstance, yet we all know they are not the end-all, end-all. Due to the nozzle opening of the ear-tip stage is affected, due to shape of ear-tip the fit is affected. Yet, also if stage is decreased with a smaller nozzle circumference opening, bass is added to the replay. With such basic ideas in replay, there can be further abstractions depending on personal ear anatomy and over-all IEM shape.

The two things:
This means two very important things which may seem conflicting? While the HISENIOR OKAVANGO was brought into a dense style of bass with longer/narrower nozzle openings, the stage was somehow not as different. There are still unarguable aspects of these changes, namely psychology…..hence when you change to your normally used wide-bore ear-tips you can subjectively note a broader stage, and lesser bass focus. Yet at times (and depending on differences in IEM playback character) a bigger bass replay will seem to add stage!

This brings us to the final cable argument that suggests cables offer different aspects of end sound in contrast to simple EQ settings. I would like to suggest that just like the ink pen is an advancement over the paintbrush, and the paintbrush is an advancement over the simple rock scratching on the cave wall, the use of cables brings about an advancement of details. The confusing part of understanding this concept is that of tone personality. That in fact EQ offers a blanket form of charge, where at times cables will only alter a segment of playback, except the other thing they do is add character. Such character is often difficult to describe yet found across the same metal choice in various manufacturers' cables and numerous different IEMs applications. It’s a combo feature normally like the OSG’s graphene causing a smoother replay but combined with a weighted treble opposed to silver. Silver offers-up an increase of energies into the stage spatial optimizations through imaging energy, yet also normally containing thinner density.

Per Dsnuts:
Silver for its highest transparency and stage enhancing.
Gold for that rich tone and depth.
Palladium for that remarkable imaging and detail.
Copper for body and warmth.

Let us not forget the Palladium is also used as an additive with gold and silver in the Penon Leo Plus. Graphene is one of the main additives besides silver plating the copper wire with the Penon OSG cable. And of course we as humans slowly gravitate towards a specific cable in use (our favorite cable) often finding that it seems to add the properties we like to numerous DAP/IEM combinations.


The Rhodium Plug:
Rhodium Plug v Standard Plug:
Rhodium is inherently thinner (in response) ever so slightly, yet bringing a mix forward, and polishing the faint treble elements, making them have a (brighter) reflection of luster. Still totally clear, but a subtle repositioning of importance, a repositioning of relevance to one another, as the audio stage took place. So think of regular copper plugs as thicker and warmer offering a basic full background, and ever so slightly darker imaging.



The Palladium Plug v Rhodium Plug:
Doing normally what the Mix Cable does naturally, the sound was bigger, more forward and wider…..showing an increase in stage from the included cable and included plug……but now referencing in comparison to the Rhodium Plug.

The was actually an unexpected Palladium clarity and forwardness in contrast to the Rhodium plug? A definite widening and bringing forth of imaging. Such Palladium imaging was closer and farther outwards, yet seemingly louder?

To tell you the truth I loved the Penon Mix Palladium Plug combo with the Noble Audio Encore K-10. Such a combo was the true highlight of my day, I liked it better than the Rhodium plug in place. Just big authoritative imaging, that looked almost as if you could touch it? While never strident or too bright, the images were simply more 3D?


This test had to take place as the Rhodium Plug was made for the OBSIDIAN cable. This test was in-fact my very last test of the Rhodium Plug. And when this review started I didn’t understand both the prescribed combo of the OBSIDIAN cable and the Rhodium Plug. But later after learning the sound qualities (the trimming) that the Rhodium Plug does, just by its nature, the what I call “stingy” demeanor of how the Rhodium acts…..well finally I understood its uses with the OBSIDIAN. It’s a way to correct the OBSIDIAN and make it cleaner. So I will use one of my favorite IEMs ever with the OBSIDIAN, the Noble Audio K-10 Encore and see how it fairs? Strangely smoother and extending out harmonics into longer trails….not so contrasty, thus reserved and correct. Simply smoother and more readily accessible, but only a slight difference really? It made less difference than I expected, but again that’s the psychology involved because you’re told the plug was made for a cable, you approach the scenario with far greater expectations, which in reality are often never met.

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You know before when I would listen to the (Rhodium Plug) Penon OSG cable or (Rhodium Plug) CS02 cable I would always wonder how much the plug contributed to the overall sound. Truth to be told, those two cables are some of my most favorite cables ever, and even more so in that they are both reasonably priced. Strangely, just like sources or IEMs……..cable prices seem to go along with material costs and subsequent performance gains relative to cost of ownership. Yep, more expensive stuff just sounds more elaborate and better when correctly matched into synergy. I have spent years trying to find the performance loop-hole? Such a find would be a $40.00 IEM that sounds like a $400.00 IEM, or a cable included with a $20.00 IEM that sounds like a $200.00 aftermarket cable. But guess what? Somehow there are laws which govern the build of this stuff that follows an order. Meaning if there really was a $40.00 IEM that sounded like a $400.00 IEM it would be the talk of the town…..but no such things exist……at least not yet anyway. What this means is you get just what you pay for. Now sure, there are performers and lackadaisical performers, that’s just natural. But we would all agree when synergy is found it is golden. You know those times when all the equipment and music comes together to make an outcome truly an experience. And that’s our goal, to choose wisely and reap the benefits.

Now I will be the first person to say these two plugs in question seem the most like audio jewelry. They do! The IEM, the DAP and the cable make the most difference, we know this, it’s not arguable. Adding a small difference of metal plating on to the end of a cable creates a small difference, yet many audio manufactures charge $100.00 for this Rhodium or Palladium ad. Yep, you can have your cable with this extra slice of cheese, or not. :)

To Rhodium or not to Rhodium?
Back to my original question, you know it still isn’t answered in that it would require a Penon OSG cable and an OSG cable with a regular plug to tell the difference. It would require a CS02 cable and a CS02 cable with a regular plug to tell the difference too. So this additive of a Purple Palladium or Rhodium Plug that we can place on the end of various cables to change the sound in the next best thing. Truth to be told the Rhodium plated 3-in1 was invented as a way to enhance the Penon OBSIDIAN cable, but other success stories are found to be true too. Namely an unexpected combo inside of using the Noble Audio K-10 Encore and Penon Mix cable. Such a combo was often avoided for fear of being too bright, yet somehow this time it showed focus on the differences of the Rhodium Plug, and Purple Palladium Plug in comparison to the Mix Cable included Plug. And sure enough those differences were spelled out the same as with the HISENIOR OKAVANGO, only just slightly clearer and with greater accuracy due to the Noble Audio K-10 Encore additive drivers and tuning stance.

Remember often TOTL, or past TOTL IEMs will give us a clear window into cable changes due to perceived resolution.

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What’s it all mean?
Quite simply you have a relatively inexpensive way to fine-tune your already acquired equipment. Truth to be told, this change is the farthest from a big change, but can be appreciated for an extra 10% of personality, in the right place. But the way the human mind works, we can focus on that 10% and somehow it becomes larger, way larger than I want to say…….but more than a simple 10% change. This change could be like studying the birthmark on a face, such a seemingly small 1% spot, all of a sudden sets off the whole look of a person?

Rhodium v Palladium:
But in truth there was a difference between the Rhodium Plug and the Palladium Plug. Where the Rhodium was more stingy with the out-put, holding back and refining a stance, the Palladium was more forward and vibrant showing more colors and closer imaging? Though I can totally see how both could be of use in the right application, it was just in contrast to one another the differences were (totally) noticeable. With that said, the regular included copper plugs offered a thicker response of slightly less contrast, and because of the contrast seemed to show a more evenly distributed response? Thicker, warmer and holding a denser background stance? And some may only want that effect? Where especially with Palladium Plug (in contrast) showing a closer and in-your-face style of imaging.............gaining resolution and texture while still not sibilant or too bright?

Depending on your original cable:
Yep, so to try and simplify things, keep in mind that your original cable is going to offer the most difference between sound responses. Yep……but there may be a difference that is unpredictable and gains advantages simply by using whatever plug you have at hand. Now remember this changing of plugs is way faster than changing cables, as it is only one change, you unplug the DAP, switch plugs and put it back. It takes all of 1/2 a second to learn the differences. You can even pause the song for a moment and simply continue on your way. Also remember part of this is going to be taste and preference, as there will be not always the same experience for everyone, in fact I can guarantee you will not have exactly the same results as I. Except there are perceived responses that are similar between equipment, thus a form of learning takes place at Head-Fi with comparing notes.




I want to thank Penon/ISN Audio for the love and for the Penon Rhodium plug and Penon Purple Plug review sample.

These are one person's ideas and concepts, your results may vary.

Equipment Used:
Sony WM1A Walkman DAP MrWalkman Firmware 4.4mm
Sony TA-ZH1ES DAC/AMP Firmware 1.03
Electra Glide Audio Reference Glide-Reference Standard "Fatboy" Power Cord
Sony Walkman Cradle BCR-NWH10
AudioQuest Carbon USB
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