The Ra C-Cu isn’t worth $100, much less $10,000.

I have no good things to say about this. It is wrong on so many levels that it’s hard to list them all, so let’s start with the bass. I understand that the Ra C-Cu is built to be an open-backed kind of IEM for imaging purposes, but there are ways to tune these kinds of IEMs without completely screwing over the bass response. The exalted MDR-EX1000 for instance, or perhaps the Audeze LCD-i4, both great examples on how you can still get great bass extension even without a fully sealed enclosure.

But the Ra C-Cu doesn’t have bass extension. It’s basically more earbud than IEM. And if that’s not enough, the Ra C-Cu has this resonant hump in the midbass that completely muddies the mids, so rather than getting the clarity of a rolled-off transducer like, say, the Koss KSC75, it still presents the bloat of an overly-bassy pair of IEMs. All of the drawbacks, none of the benefits.

Let’s talk mids now. The easiest way to describe them would be “unnatural” but if you want to be extra-nice, I guess you can call them “unique-sounding”. You can probably get used to these after hundreds of hours of listening, but you can do the same thing with $5 buds. Not an excuse.

You would think that treble would be the best thing about the Ra C-Cu given its unique AMT tweeter, but no. The treble is all over the place with random spikes and dips, and sometimes even gets sibilant despite its somewhat subdued overall nature. There is honestly nothing special with the detail or speed and it makes me question why even use the AMT drivers in the first place.

For the paltry sum of 10 grand, I think you’d expect near-immaculate product quality. Alas, this Ra C-Cu comes with significant channel imbalance.

And to the naysayers, to the goalpost shifters who would now begin to question my testing methodology, here is my statement to you and everyone else reading this.

The best, most exotic cable cannot fix the Ra C-Cu.

All the power in the world will not fix the Ra C-Cu.

No source, DAC, amplifier or otherwise, will magically make the Ra C-Cu sound good.

You can burn these in till the heat death of the universe, but it’ll still be bad.

Tips can only do so much, and the Ra C-Cu is too much.

It is a fundamentally flawed product born from either sheer incompetency or laziness, and I’m not sure which is worse. Fixing this will require an entire overhaul of the design and tuning philosophy, and there is nothing the end-user can do short of a full driver transplant that will make these truly worth the price.

I hardly ever use the following statement due to the subjectivity of the hobby, but I think this is an absolutely appropriate time given the level of inadequency. The Ra C-Cu is objectively bad, not just as a value proprosition but in an absolute sense in the absence of pricing. oBravo’s own $320 Cupids are better than them, not as a compliment to the Cupids but rather a testament to how painfully awful the Ra C-Cu is.

Get something better if you have that kind of money to burn, like the VE Erlkonig or something.