The Duo's twin drivers and impressive tech package are all you need to enjoy an immersive sound experience in an IEM. By pairing a dynamic driver and tia Balanced Armature with revolutionary techs like Apex Core and Wave Sync, 64Audio has produced an impressive IEM that you can enjoy anywhere, anytime.
Everything you need is included with the 64Audio Duo IEMs!
The Duo comes with proprietary 64Audio technologies for enhanced comfort and sound.
Listen to the Duo for the first time, and you'll quickly notice its big natural sound courtesy of the single dynamic driver handling and the tia Balanced Armature.
Bass-heavy tracks rumble with natural impact and texture, while instrumentals and vocal-centric tracks come alive with life-like clarity and tone.
The 64Audio Duo will play back your music with extra energy that will leave you tapping your toes for hours on end.
One of the Duo's most unique features is its semi-open back shell design, which looks amazing while offering enhanced sound.
The open design enhances in-ear comfort by venting out extra air - all while extending the soundstage for a truly immersive listening experience.
The Duo boasts a complete tia system, consisting of the tia Open Balanced Armature, Single-Bore, and Acoustic Chambers system.
These three systems allow the Duo to deliver sound from its drivers straight to your ears for unmatched clarity, detail, and tone.
The Duo is the first of its kind to feature Apex Core technology - a variation of 64Audio's patented Apex tech, designed to provide enhanced in-ear comfort and sound.
Derived from 64Audio's deep understanding of air movement inside an earphone, Apex Core enhances sound while ensuring minimal ear fatigue.
Air produced by the Duo's drivers is vented out naturally through the open grille design for expanded soundstage and reduced risk of in-ear pain or fatigue - perfect for long listening sessions at home or in the office.
The Duo features Wave Sync technology to ensure the dynamic driver and tia Balanced Armature produce perfectly matched sound
Meanwhile, LID or Linear Impedance Design technology ensures the Duo's drivers sound consistent across all frequencies no matter where you plug it in.
The Duo comes with 64Audio's Black Premium Cable:
The Duo covers frequencies starting from 20hz and extending to 20kHz - allowing for a wide range of frequencies to be reproduced accurately.
Duo:
2 Drivers
20hz – 20kHz Frequency Response
9Ω Impedance @1kHz
Integrated 2-way Passive Crossover
U4s:
4 Drivers
10hz – 20kHz Frequency Response
11Ω Impedance @1kHz
Integrated 4-way Passive Crossover
Our Analysis:
Nio:
9 Drivers
10hz – 20kHz Frequency Response
6Ω Impedance @1kHz
Integrated 4-way Passive Crossover
Duo:
2 Drivers
20hz – 20kHz Frequency Response
9Ω Impedance @1kHz
Integrated 2-way Passive Crossover
Our Analysis:
The 64Audio Duo is an entry-level universal hybrid IEM. Priced at $1,199, the Duo offers an engaging sound with its powerful, detailed bass and smooth top-end tuning.
| Specification | Description |
| Driver Configuration: | 1 tia High Driver – 1 Dynamic Low Driver |
| Frequency Response: | 20Hz – 20kHz |
| Sensitivity: | 98 dB/mW Sensitivity |
| Crossover: | Integrated 2-way Passive Crossover |
| Impedance: | 9Ω Impedance @1kHz |
| Apex Technology Isolation: | -12dB Isolation apex Core Technology |
Shipping is FREE on all orders to customers within the USA.
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We get it. Audio gear can be subjective. That's why we offer our industry-leading 365 day return policy. Here's a quick rundown;
We get it. You've got a lot of choice when it comes to online retailers. Here's why we think you should shop with us at HiFiSoundGear.
Amazing customer service. Adam went into great detail with his experience on these IEMs. Would definitely go to him again!
Good communication throughout the process with fast shipping.
It's such a pleasure doing business with Adam and Lauren that I am honestly looking for an excuse to buy more equipment there. I don't really have a good personal audio store anywhere around; and while I am not exactly morally opposed to Amazon or whatever, it's so much nicer dealing with real people and a small business. I cannot even imagine what else I could ask for.
Great work, to communicate every step along the way. Very personal touch. I will visit the office one day to personally thank them. I love the website. I love the product. I love the state where they are located. Awesome awesome awesome!
Everything went really smoothly and I'm enjoying the headset I purchased. It shipped quickly and arrived well packaged. I had a question about my purchase and received a quick response from the seller. I would buy from HiFiSoundGear again.
Unexpected as in very pleasantly surprised at the sound quality coming out of these :)
I took my Mega5-EST and hooked em up wirelessly and don't miss the wire sound AT ALL!! IMO the wireless sound was 98% of the wired sound without the PIA of the wire. Unless you have some amazing source gear, which thanks to Adam at hifisoundgear I do, you would be hard pressed to hear a massive difference. Especially with a phone as your source.
I did A/B noble Fokus Prestige vs Go pod w Mega 5 and gotta say l, there is more balanced sound with the Go pod chain then the Prestige on its own. To be fair the Mega 5 punches WAY above its price... so the 2 are a match made in heaven.
I find the connection very stable as well. I've used my iPhone AAC/SBC as well as with FiiO BT11 to get other than Apple codecs and was pleasantly surprised as well.
The ear hooks are very comfortable. Actually prefer them to the wire hanging over my ear with a tie behind my neck. For some reason that's hard to get used to and pulls as I wear loose shirts. The hooks stay in as I like to move around a bit. Also the weight is better distributed than other wireless IEMs as the components are in the hooks. The prestige, unless I have foam tips, which I'm not a fan of, will pop out of my ears when I move around. These stay stable and I do not have to re-seat the IEMs to get that great bass nearly as often with other wireless IEMs.
Battery level has been all day 10 hrs so far with intermittent breaks and still have 28% left.
The case also is deep enough to fit the Mega w hooks as it charges which is very convenient. Some IEMs may be too big but they fit with a tad bit of room to spare.
Of course having the flexibility to swap out your favorite IEMs as needed is awesome!!
5 stars for the Go pod and more importantly 5 stars to Adam and his team for such amazingly awesome customer service!! You guys ROCK!! Thanks :)
The iFi Audio iDSD Diablo 2 is an absolute masterpiece in the world of portable amps. It delivers an audio experience that redefines what’s possible in a compact, travel-friendly device.
To all the "haters" out there who mention that the 5180mw output is an overstatement and the "balanced" is not a true balanced output... I say whatever... it drives anything I throw at it with aplomb! FostexTH900mk2, ZMF Caldera Open and Closed, ANY IEM my friends and I have tried ...too many to list. If you need more power than this portable titan.... well you may have hearing loss. And it drives all I mentioned without using "beast mode" (they refer to it as Nitro (1 of 3 settings)). If anything, it could use a lower gain option / IEM match for some sensitive IEMs.
The implementation of BT 5.4 (supports all codecs) is a welcomed addition for quality, but in general, the distance it can be from the source is very small for consistency. That is not a Diablo issue, but a BT5.4 issue IMO.
As for the sound quality...simply unparalleled. I have compared this to desktop headphone amps in the same price range and I would put it toe to toe with them. It even ran close to my buddy's Burson Soloist 3x!!! and the Diablo 2 is portable :)
I run it using A&K SP3000T and it oozes warmth and richness in the lows and highs WITHOUT covering/smoothing anything up in the mids, which is my jam.
It is on the heavier side and will still fit in a pocket... barely. built like a brick. At the limit of what I would like to carry but totally worth it! I get about 6 hours of the 8 rated battery with constant listening, no Bluetooth on, hard wired, IEMs / Caldera tested on the battery life.
In conclusion, the iFi Audio iDSD Diablo 2 is nothing short of extraordinary. It’s the ultimate portable amp for those who refuse to compromise on sound quality, power, or versatility. If you’re serious about your audio and want the best experience on the go, the Diablo 2 is the perfect choice.
Shout out to Adam, a massive THANK YOU!!! for your absolutely OVER THE TOP customer service and shopping experience :) :) Seriously, your dedication and attention to detail have been nothing short of exceptional.
With all the online ordering over the years, HifiSoundGear provides the best service I have encountered. It was as though they were good friends. They responded so nicely to all my questions about the product and shipment. As it works out, while I liked the IEM's, I concluded they were not sufficiently different from the ones i had been using. Again, for the process of returning and getting a refund, they could not have been nicer. Buying from them was a first rate experience.
Recently had a great experience with Adam and Laura. I requested a price match for the FiR KR5 and it was such a painless process. Adam and Laura’s communication is top notch! Adam even sent me a personal thank you video. In my experience, this level of service is hard to come by these days. I highly recommend going through HifiSoundgear for your audio needs….I know I will be going forward! Thanks Adam and Laura!
The quality of service, level of help provided, and overall customer satisfaction is beyond anything I have experienced. I cannot say enough good things about the people who belong to this company!
As for the U4S, these are my first foray into 64 Audio but I am SO thankful that I got to experience them! My goodness the soundstage, bass response from the m15 module, and overall quality is just great!
Please, buy from these wonderful people! And if you can swing it, get a set of U4S! You will not regret it!
Only complaint is the cable. For the price, I expected better, but it works well and is just fine.
Thank you HiFi Sound Gear! I look forward to purchasing more from you in the future!
These are the closest TWS gets to pure IEM listening. You get the wide soundstage. They scale quickly. They have that satisfying bass slam often missing in TWS. The layering is just right and resolution is mesmerizing. Oh yes, you get the convenience of taking them on the go and they are truly comfortable. Noble has achieved a superior status in my eyes with the FoKus Prestige. I look forward to listening to them on my walks when I don’t have to take my DAP. Adam is one of the greats in this business. His commitment to customer service is exceptional. You aren’t a customer, but a client. He helped me after losing my first pair and just went above and beyond to ensure that I was shipped a new pair in less than two days. I am completely satisfied and impressed. You will be too. Thank you and looking forward to my future purchases from your establishment.
HifiSoundGear offers exceptional quality products and unparalleled customer service. Their wide selection of high-end audio gear, including in-ear monitors and amplifiers, are praised for delivering outstanding sound clarity, detail, and an immersive listening...
