Penon OSG – Wonder cable

If you're looking for a cable with a unique sound profile in that it doesn't affect the frequency response much aside from a slightly leaner lower mids and smoother upper mids, but rather inflect the IEMs signature with a black background, tighter bass and sharper attack and faster decay then the Penon OSG should be at the top of your list!

Product Page : https://penonaudio.com/penon-osg.html
Price : 319$

Introduction

Like most people I know I have enjoyed Penon as an online shop, a trusted distributor of many brands I love like Dunu, Astrotec or ISN to name a few. But Penon also began manufacturing products a while back, starting with great value for money cables and is now evolving into a more premium segment with the OSG and now the flagship Totem.

Priced a little over 300$, the OSG is a silver-plated copper (OCC) mixed with Graphene, first time ever in an IEM cable… In the audio world graphene coated dynamic drivers have become common and it can be found in high end audio cables as well. Let’s dig a bit more into this…

A bit more about Graphene

Graphene is quite a unique material which has been dubbed “wonder material”. Graphene is a thin, two-dimensional layer of carbon atoms arranged in a hexagonal lattice (picture below).

In 2004, Professors Geim and Novoselov discovered graphene when they were able to extract a layer a single atom thick of a block of graphite, which earned them a Nobel Prize in 2010. Graphene is dubbed a 2D material “sometimes referred to as single-layer materials, are crystalline materials consisting of a single layer of atoms.”

Graphene is ultra-light, immensely tough, yet flexible and stretchable. For instance a square meter of graphene weighing a mere 0.0077 grams can support a stunning four kilograms. Graphene conducts heat and electricity much more efficiently as well. Both properties could make the OSG a very sturdy cable but with better conductive capabilities than non graphene cable. We’ll see in the review how it effectively translates…

Build, ergonomics and comfort

Build

The OSG is a 4 strands cable, each strand packing no less than 71 cores. The braiding is flawless both before and after the Y split and the OSG cable looks very premium and solid. The carbon fiber metal splitter and slider look slick and everything is perfectly adjusted. The termination is rhodium plated, in my case 4.4.

Ergonomics and Comfort

The OSG has great ergonomics and there is no microphonics. I love the color coded 2 pin connectors this is something that annoys me with so many cables to have to look for small poorly contrasted L/R markings, with the OSG you also have color coded rings on the carbon part of the connector. Kudos!

The OSG doesn’t pull IEMs down while moving around, it’s not an heavy cable which is good on the go. There is no preformed ear hooks which means you have to rely on the slider to lock the cable into place. This is where I have a minor gripe with the OSG, it can happen on the move that the slider gets loose and needs to be readjusted. I would have liked a just slightly tighter slider there. Other than that, the OSG is quickly forgotten and is very comfortable.

Sound

The OSG is a very interesting cable, as it’s fairly neutral across the frequency range with a very linear profile. No matter which IEM I plugged in, the OSG was faithful to its signature and as such is not the “analog EQ” one might search for in a cable. It does not expand soundstage like some cable do nor does it make it smaller but I found it provided a bump in imaging quality. Does that mean the OSG doesn’t affect the sound? Absolutely not!

First it features an impressively pitch black background which definitely enhance note contrast : basically every IEM I have plugged it in, as we’ll see, sound more focused and resolving. Second, it will greatly tighten the bass presentation helping bring more control and punch to the table. Third, it will provide the most accurate tone your IEM is capable of.

Bass

This is the first cable I have heard since Dunu Hulk to be able to tighten the bass this significantly. Actually after some A/B, the OSG goes further because it’s so neutral to the frequency response. The OSG doesn’t add bass presence it just makes it so much tighter with exceptional control, which incidentally – combined with the black background and sharper attack and faster decay – brings better perception of speed. This as we’ll see in pairings section makes a bring difference in the overall presentation of my IEMs.

Mids

The OSG didn’t affect the midrange frequencies by bringing more or less lower mids (or marginally so), but its exceptional blacker background help instruments separation with its greater contrast. The OSG also bring the best tonal accuracy of all my cables, leaving only whatever tonal coloring the IEM itself applies. Last but not least, I found the OSG to bring more energy and speed with a sharper attack and decay of notes.

Treble

The OSG is quite consistent and doesn’t color the treble or add/remove any presence in either the lower or upper treble sections. But again the black background makes up for greater note contrast, I felt my lower treble had a bit more energy and upper treble is delivered with better contours making the OSG a resolving cable.

Pairings

Tansio Mirai Zodiac
If you’ve read my review, the Zodiac is a highly transparent IEM so it was interesting to start there with the OSG. Right away it was clear the OSG doesn’t affect the overall frequency response, the Zodiac is even more neutral than all my cable collection with a leaner and punchier presentation (but most cable I own are more organic like Hulk, Blanche, PW n°10, Oslo, Tiburon 8 wires).

The blacker background takes imaging a bit further enhancing separation and note contrast bring more dynamism to the table as well as sharper note attack across the range.

With the OSG the bass presence and balance is preserved. Compared to my other cables that do add presence, the OSG is comparatively leaner with more details bringing the Zodiac closer to a pure reference bass. The bass is also punchier but the gain is not as pronounced as my other IEMs as the Zodiac inherently has great control in this area. It just takes it one bit farther and I definitely appreciated this variant of the Zodiac sound. This is a very different proposition than the AG8 with Zodiac for example.

I found the mids to be more linear with the OSG than I am used to, less lower mids than my other cables while retaining good bite for a very balanced and articulate midrange. Again the OSG brings the Zodiac towards a more reference presentation. Its blacker background provides a more vibrant and focused midrange presentation with great clarity. Last but not least the OSG made the Zodiac more accurate but at the expanse of the more organic presentation I am used to.

Treble wise it’s more of the same, I found the treble to be more accurate and the black background helps note contrast and I subjectively felt the OSG made the Zodiac even more resolving. The sharper note attack and quicker decay made for a clearer and cleaner treble with overall more energy.

Earsonics EM10
This is still one of my favorite custom IEM if you’ve read my review you know I consider it a most under rated IEM that can compete with the best and is no less good than the highly praised Grace. The EM10 is a highly engaging all rounder CIEM with totl performance across the board. I also consider the EM10 to be among the very best BA mid bass around no less.

I must say I was quite eager to see how the OSG would pair with it as I suspected it would make a very different pairing to what I am used to. I was right and the EM10 is quite a match with the OSG. The only thing I noticed is the gain of the blacker background I found in other IEMs was little to none with the EM10 as it features a pretty black background already.

The EM10 bass is a deep, rich, strong and full bass with a mid bass tilt. The mid bass is hefty with superb slam. The OSG is bringing more balance to the EM10 bass : the sub bass presence relative to the mid bass is increased thanks to a tad leaner and more controlled mid bass. The sharper note attack, quicker decay gives a more focused bass presentation and the little is lost in mid bass quantity is gained in tightness and impact.

The EM10 midrange is a bit leaner than I am used to with the OSG, it’s subtle but it’s there and it makes the EM10 a little less full sounding but also tonally more accurate. The sharp attack and faster decay again make for a more energetic and focused presentation.

The EM10 treble I found was the least affected and remains consistent with my experience of the EM10 with other cables.

Custom Art FIBAE7
I was quite keen to see how the OSG would pair with my favorite IEM and in this case I suspected a superb pairing with this rich, lush and smooth sounding IEM. The OSG stayed true to what I had noticed before : it doesn’t affect an IEM by shaping its frequency response into something different, but brings its own distinctive qualities to the table.

The FIBAE7 bass has great presence starting with impressive sub bass that bring unusual physicality for a balanced armature. Like the EM10 the FIBAE7 has great mid bass slam with a little less control though. The OSG makes the FIBAE7 bass tighter : sub bass has a tad more control but the mid bass is significantly tighter and punchier and I found myself pushing the volume with a big grin on my face.

The FIBAE7 mids are full sounding, smooth, rich and textured with fairly forward lead instruments and vocals. Contrary to the EM10 I didn’t notice leaner lower mids but the FIBAE7 has quite significantly more lower mids presence. On the flipside this time around I noticed smoother upper mids and tracks like Hank Levy “Whiplash” even at higher volumes didn’t go up to my personal upper mids treshold like they usually do with the FIBAE7 on that track.

The FIBAE7 has energetic treble with great lower treble presence and refined upper treble presentation with good extension. The OSG stays true to the FIBAE7 signature, with maybe a slightly tamed lower treble but it’s not at the expanse of the treble excitement, more of a smoother take.

StealthSonics C9 Pro
The C9 Pro is quite different from the previous reference C9 flagship with a highly engaging and smooth with a strong bassline, full mids with superb vocals and very refined and elegant treble. It’s a thick and warm organic signature with good air and treble energy. I had a feeling that the OSG would make a great pair with the C9 Pro.

And I was very pleased by the combo indeed. The OSG has a knack to stay true to the IEM baseline signature adding a blacker background, tighter bass, a more linear midrange and accurate tone.

The C9 Pro has the most mid bass emphasis of all my IEMs with a fat, thumping mid bass with rich textures. The OSG brings a bit more balanced bass presentation with a little less mid bass emphasis highlighting sub bass a little more. The bass is tighter and snappier and feels quicker with a sharper attack and quicker decay. This provides more clarity to the bass and even if there is less mid bass presence it’s not detrimental to the ability of the C9 Pro to convey rhythm as it packs a lot of mid bass to beging with. There is plenty mid bass left and still mid bass focus and the bass line is still very strong. I really love what the OSG brings to the C9 Pro here and it’s probably the best synergy of all IEMs tested so far.

The same applies to the midrange where the improved linearity with a tad less lower mids makes up for a less warm and sweet presentation bringing a more focused midrange while not removing its very organic nature. It’s still very full mids, smooth but just a tad less warm and more articulate. I must say it brings the C9 Pro to new heights and I love the combo.

The treble presentation is consistent with other cables but with a more accurate tone still slightly warm hue but less than other cables.

ItsFit Lab Fusion
If you’ve read my Fusion review you know I like the punchy and clear sound, with great soundstage and fantastic imaging. It’s more of a reference tuning and I suspected the OSG would further those qualities.

The Fusion already has superb bass control with great punch so this time the benefit of the OSG was more marginal. I didn’t notice huge changes compared to my favorite cable with the Fusion, namely the DITA Oslo. The same story goes on with the Fusion midrange which is clean and clear with a reference take. The OSG doesn’t affect the midrange very much except taking it one step further toward a pure reference mids with extra background blackness for a tad better note contrast. In the treble section, the same does apply and I didn’t notice a lot of changes compared to the Oslo. Overall the Fusion is the least impacted by the OSG among all my IEMs.

Verdict

In a market where premium cables price are skyrocketing and can honestly be questionable investments, there is room for high quality and high value cables at a fraction of the price. The Penon OSG falls right into what I consider to be the sweetspot of fair price and great build along with strong performance that bring you 80% there as compared to flagship cables.

Penon is leading the pack innovating with the first graphene infused cable and in a mid tier cable no less! It has a unique sound profile in that it doesn’t affect the frequency response much aside from a slightly leaner lower mids and smoother upper mids, but rather inflect the IEMs signature with a black background, tighter bass and sharper attack and faster decay. As we’ve seen this means fantastic synergy with more organic IEMs as it doesn’t change their underlying nature while bringing a more focused and energetic presentation, with also a more linear response with a accurate tone. The picture is less obvious with more reference IEMs where the OSG has the merit of letting their inherent strength express to the fullest, but it won’t add or remove anything either if they already possess a black background, reference mids and tight bass.

Listening notes
I spent approximately 40 hours with the OSG cable, listening on iBasso DX160 and Hiby R8. 

Special Thanks
Thanks to Penon for providing a review unit of the OSG cable . As usual, this review is my honest opinion. No incentive was given for a favorable review.