First it was BA bass... now it's modular cable plugs - I seem to be covering audiophile taboos lately.
Not that there's anything wrong with controversy, and swappable connectors despite gaining widespread acceptance in recent years have generated their share of heated exchanges among audiophiles.
You see some of us have felt solder joints are preferable to friction-fit IEM cable plugs & 2pin/MMCX connectors because they conduct electricity better, so theoretically they perform better. Others argue the extra swappable flexibility far outweighs any minuscule performance gains we may well struggle to hear.
As someone who's DIY-ed cables, my stance has always been it seems counterintuitive to compromise performance with a swappable plug on an aftermarket cable who's primary purpose is to enhance performance to begin with, and I'm happy to forgo added flexibility to achieve that end.
But... what if there was actually a
sonic benefit to swappable cable plugs?
That thought immediately hit me when Penon Audio offered to send one of their new modular
Obsidian cables in exchange for a review & mentioned they'd include not one, but two sets of modular plugs - Purple Copper and Rhodium-plated, each one with different tonality, and technical performance.
So is this the moment I swap to the modular-plug camp, or do I refuse to bat for the other team?
Packaging
The USD $149 OCC copper + 18k gold plated OCC copper
Penon Obsidian arrived in a small cardboard box, inside of which is a sturdy carrying case, the cable itself, a shirt clip, and a set of modular plugs.
My understanding is that when ordering the
Obsidian if you select the '3-in-1 Version' you'll be purchasing the modular cable I'm reviewing here, and will receive a set of 2.5mm, 3.5mm & 4.4mm copper plugs. The
Rhodium-Plated plugs you can order separately.
It's a shame there isn't an option to add a 4.4mm Rhodium Plug on the Obsidian's product page, because I really do feel a lot of the value of this cable lies in owning both types of plugs and being able to tweak the sound accordingly - instead you'll need to add a separate item to your cart to purchase a Rhodium plug, along with the cable itself.
Ergonomics
At 37.5 grams, I find the modular Obsidian lies in the goldilocks zone of containing enough individual wire cores (400 total in this case) to provide an appreciable improvement to IEM performance, without being so heavy as to make me question whether the weight penalty is worth the audible gains.
That's always been my issue with beefy 8 wire cables - they can sound terrific with boosted dynamics & improved bass impact among other benefits, but inevitably I start wondering if carrying all that extra weight on my ears is really worth it. They don't "disappear" during long listening sessions the way smaller 4 wire cables do, and their stiffness can be a reminder I'm wearing one with each turn of my head.
The Obsidian feels like a "normal" 4 wire cable, with very pliable insulation (which feels like PVC) that helps it drape effortlessly. The modestly small & light Y-split & chin slider also benefit ergonomics, as does the lack of additional earhook insulation which has become my comfort preference.
Modular Plug System
The Obsidian's modular plug system works similarly to Effect Audio's Term-X and most modular IEM cable systems - basically you unscrew the section just below the barrel of the plug itself, remove the plug, insert the new one & re-tighten to secure the new plug in place.
Four pins connect the plug to the wires of the cable, and the plug can only attach one way so there's no need to worry about reverse polarity.
It's not a revolutionary system, nor does it avoid the common pitfall of modular plugs - that with enough force you can remove the plug without unscrewing the barrel, so potentially there's a risk the plug may detach at times you don't want it to. Admittedly that's not likely to occur unless you yank the cable quite hard, but psychologically a fixed soldered plug can feel more secure.
The other issue surrounding modular plugs is sonic degradation, since a solder joint offers superior conductivity (and potentially better audio performance) than a friction-fit connection. Opinions vary on just how much real-world performance is affected however, and Effect Audio have certainly laundered praise for the their friction-fit ConX 2 pin/MMCX connectors with few complaints of adverse performance.
Sound Performance
When I reviewed the white-jacketed Obsidian cable bundled with the
Penon Impacts in my
2023 Cable Shootout I didn't come away amazed at its' performance, though in fairness it was up against vastly more expensive competition so perhaps that's not surprising. However it meant when Penon sent me this new Obsidian my expectations weren't sky high.
The white-jacketed Obsidian was a 4.4mm fixed-plug cable, and I wonder if it was built using different solder or 2pin connectors because this new iteration sounds different. The white Obsidian felt very midrange-centric, whereas this new modular Obsidian feels more V-shaped which I prefer.
Bear in mind locking down the "sound" of a cable can be a tricky business given they affect the performance of each IEM a bit differently, but the modular Obsidian has impressed me by deepening the bass of IEMs I use it with, increasing the perception of background blackness, improving dynamics and enhancing note weight.
The Obsidian also improves resolution slightly, and though this isn't a behemoth 8 wire cable that'll grow the soundstage massively it does have a way of relaxing stage dimensions to give performers more room to breathe without necessarily making the stage feel like a cathedral. Its as if the Obsidian gives the performance more headroom, in contrast with cheap stock cables that make your system feel like its gasping for breath. Improved dynamics probably play a role in that.
Of course the novelty lies with the modular plug system, so naturally you'll ask - do the copper & rhodium plugs sound different? Yes, I find they do. The differences are more subtle than the changes between IEM cables, and you'll notice them more on some IEMs than others.
To summarise them, the Rhodium Plug generally sounds airier and "cleaner" with more prominent treble and slightly better technical performance, whilst the Purple Copper Plug feels earthier, imparting more of a stereotypical copper tonality that sounds smoother. Things aren't quite that simple though, as the performance of each plug is somewhat determined by the IEM you pair the cable with.
IEM Impressions
As always the performance of an IEM cable can't be evaluated in a vacuum - you need to pair them with different earphones and observe the results to really get a handle on their characteristics.
So I put the modular Obsidian through its' paces with a number of IEMs at hand using the
Cayin N8ii set to hi-gain, in solid-state mode with P+ enabled to learn more.
ISN Neo5 (USD $289)
Using the Rhodium plug the Obsidian is brighter than the stock Neo5 cable, with a slightly wider and deeper stage. Midbass feels more prominent but sub bass diminishes. Vocals are pushed forward but I'm not a huge fan of the added brightness in this pairing.
The Purple Copper plug suits the Neo5s better, with deeper sub bass with more slam, a wider stage and more warmth. The Rhodium plug does sound cleaner with slightly better imaging & dynamics but tonality is better on the Purple Copper plug, with a modest difference between plugs.
Penon Globe (USD $329)
The Obsidian with Purple Copper plug actually sounds louder than the Globe stock cable, the midrange becomes even more present & forward with resolution increasing, dynamics also improve and the stage is a little wider. Vocals really gain an increased spotlight with this pairing.
With the Rhodium plug I don't like the tonality quite as much, with less note weight and a slightly thinner sound, though stage depth is a touch better and there's a bit more treble sparkle. The Purple Copper plug has slightly better bass impact, whereas the Rhodium plug offers a more v-shaped sound & marginally better technical performance, so it's a tossup which of the two I prefer with the Globes.
ISN EST50 (USD $449)
The Obsidian with Purple Copper plug is a great pairing I can strongly recommend to EST50 owners. It really feels like a veil is lifted with the sound not only being louder than on the stock cable, but more dynamic with a deeper stage, a more prominent midrange and increased resolution.
With the Rhodium plug dynamics increase further, as does sub bass & treble emphasis for a more v-shaped sound. Resolution scales slightly higher in the midrange & treble areas but the tonality is less warm, whereas the Purple Copper plug has greater lower midrange emphasis for a smoother sound. I prefer the Rhodium plug largely for the better dynamics but either is a great match for the EST50s.
Penon Turbo (USD $549)
With the Rhodium plug the Turbos somehow feel warmer, with more midrange presence & improved resolution, better note weight, improved imaging and a slightly wider stage, though bass feels less elevated. The Turbos sound smoother & more refined without dynamics being adversely affected.
Switching to the Purple Copper plug midbass is more emphasised, the background is a little blacker and the stage a bit wider but also flatter than with the Rhodium plug. Midbass can sound a little boomy & doesn’t blend with the rest of the presentation so well, whereas the Rhodium Plug is airier with better technical performance yet tonality isn't adversely affected, so I greatly prefer the Rhodium plug pairing.
Cable Comparisons
I also compared the modular Obsidian with a number of other cables on hand, using the Penon Turbos & Cayin N8ii in solid state, hi-gain, P+ mode.
Penon CS819 (USD $49)
Generally I find the CS819 has less bass output than the modular Obsidian, with poorer dynamics, a flatter stage, and I tend to notice treble more simply because the lower frequencies are more muted, so it doesn’t sound quite as powerful.
The CS819's tonality is excellent however, and I do think it's one of the easiest cables to pair successfully with a wide range of IEMs, but the Obsidian feels more dynamic and powerful with the CS819 sounding thinner by direct comparison.
Penon Vocal (USD $69)
Vocal is a specialist as its' name suggests, which adds more bias towards midbass though overall bass feels lot more limp than it does on the Obsidian. This decreased bass output helps Vocal feel more polite tonally, though Obsidian boasts better dynamics with a deeper stage & increased midrange detail.
Vocal has terrific midrange tonality and is a great option for 'correcting' v-shaped IEMs to make them feel more balanced, but I feel like that comes at the expense of too many other areas so the CS819 would be my preferred cable choice under $100 in most cases.
Effect Audio Ares S 4 Wire (USD $179)
The Ares S is definitely not your stereotypically-warm copper cable, and delivers a wider but flatter stage than the Obsidian, in which I notice the higher frequencies a bit more which may explain why imaging feels somewhat more defined.
However note weight feels lower on the Ares S, and tonality is also thinner with a more wispy characteristic I don't really care for.
PW Audio 1950s Clone (USD $2149)
This DIY Cardas Clear clone of PWA's 1950s cable has become my go-to standard by which other cables are judged. Comparing it to the Obsidian I notice it produces deeper bass with a blacker background, and a stage that may be a touch wider but is similarly deep.
Details are more effortlessly resolved on the Cardas Clear, with more emphasised lower midrange resulting in smoother tonality with no loss of resolution, and dynamics are higher too. The Obsidian has a more v-shaped tonality even with the Purple Copper plug, which will suit some IEMs better than others. The gap in technical performance between them is fairly small, particular given the cost difference.
Conclusion
At USD $149 the modular Obsidian cable has a powerful, dynamic sound and has become a useful addition to my cable arsenal.
There's nothing particularly unusual about that because there's a lot of great cables out there in lower price brackets, where Obsidian really sets itself apart is in the unique benefit of its' modular plugs.
Adding the rhodium plug option means you can tweak the cable in a way that won't radically alter how it sounds completely, but will make a small & meaningful difference to its' tonality & technical performance.
As someone who's previously avoided modular plugs I see this as something of a revelation, finally a credible reason for their existence beyond the added flexibility that in a world of 4.4mm DAPs & amps I no longer need. In fact now I almost wish Penon adds a modular system to the other end - swappable 2pin/MMCX connectors in copper & rhodium to facilitate even more sonic flexibility.
That's the thing about cables - the "best" cable for any IEM in your collection is always a difficult thing to predict, and throwing more money at the problem doesn't always help you solve it. Synergy is everything, so being able to tweak a cable's performance potentially makes it a lot more valuable in the long run.
It's a copycat industry where genuine innovation can be rare, so I make a point of applauding it at every opportunity - different flavours of cable plugs is a novel concept and I'm look forward to more sonically tweakable cables from Penon in the future.