The Audio Rif XR4 IEM is the flagship model in Audio Rif's product line up. Featuring an all-Balanced Armature design, Open BA Drivers, and machined aluminum chassis, the XR4 promises great sound at a value price point for working performers and discerning audiophiles.
The Audio Rif XR4 IEM comes with everything you need in the box!
The XR4 IEM packs the same research, tuning, development, and tuning expertise found in the award-winning FiR Audio Frontier Series, so you can experience the same high-fidelity sound, comfort, and durability without the flagship price tag.
The Audio Rif XR4 packs four high-performance Balanced Armature Drivers for exceptional impact and clarity.
Dual Low BA drivers deliver deep, controlled bass punch while maintaining detail integrity, while Dual Open BA drivers found in the flagship Frontier Series IEMs deliver impressive clarity and detail to your music.
The XR4 brings unprecedented performance at a more accessible price point, allowing you to experience high-end sound without compromise.
The XR4 IEM is built using premium materials for a blend of comfort and durability. The Machined Aluminum Shells provide a lightweight yet robust fit for long-lasting comfort during extended sessions on stage or in the studio.
The Audio Rif XR4 comes with a versatile cable with a modular connector system, so you can plug into your favorite sources seamlessly.
Switch between the included 3.5mm SE, 2.5mm BAL, and 4.4mm BAL and find the perfect sound for you.
Driver Configuration
4x Balanced Armature Drivers (2x Low + 2x Open BA High)
Impedance
18Ω
Frequency Response
20Hz-20kHz
Cable
2-Pin Modular Cable with 3.5mm, 2.5mm, and 4.4mm connectors
Isolation
-31dB
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.
I found HiFi Sound Gear on Google and was cautious at first, but working directly with Adam (owner) changed that quickly. I ordered the Thieaudio Monarch MKIV on Sept 9, 2025, and he had them in the very next day. Since I’m local, he set up a smooth in-person pickup in Broomfield, CO after I completed the purchase. Communication was fast and clear, and he even recorded a personalized thank-you video showing order status and my pickup window. Adam also walked me through their policies, the 5-year warranty really is five years, and the 365-day return is real as long as the product isn’t end-user damaged. This was hands-down the best customer experience I’ve had in audio retail. I’m 100% a new repeat customer and highly recommend HiFi Sound Gear.
The Noble Audio Knight is a really cool product. It's solidly built with a really nice cable, and it sounds great. The separation of the highs, lows and mids is terrific. I was never really able to heart the texture of bass guitars until I tried these IEMs. The soundstage and everything else is really source dependent, but the detail retrieval could be a little better. Overall, an awesome entry level IEM that sounds as good, if not better, than it's price tag.
Adam and Alexa at HifiSoundGear are awesome at personalized customer service (the video thank you was a really sweet touch). They are easy to reach and quick to respond to inquiries. We had an issue come up with UPS and they worked hard to get it straightened out. This company also honors their veteran customers with a nice discount-thank you!
The Noble Fokus line is the best TWS I've heard. Excellent service from HifiSoundGear -- I'm a satisfied repeat customer (quick shipping, had to make a return and they were fantastic, great follow up, etc). Highly recommend the TWS and HifiSoundGear.
Great experience from my first purchase here. Even received a personalized video from the owner for my purchase. Customer service above and beyond in all facets! Thanks so much for a fabulous customer experience!
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...
