Relay DAC 1

The one thing I detest about streaming music from my iPhone is the subpar audio playback. I come from the record player generation, when people listened to music on vinyl, of which I still have many hundreds. Digital music just sounds flat when played through most portable speakers.

The best way to fix the problem with tinny, flat audio is to invest thousands of dollars in speakers that will play your music the way it is meant to be heard. However, many of us already have a kickass stereo system and aren’t looking to buy a new one.

That’s where Mass Fidelity’s Relay comes in. It is a Bluetooth connected digital-analog converter (DAC) that connects to your existing speaker system for transmitting digital music to an analog stereo. That means, even if your stereo is 40 years old, as long as you can connect traditional RCA cables to it, you can stream music from your iPhone. We’ve got a hands-on review of the Relay for you today.


The Relay is a small box, about the size of Apple TV, milled out of anodized aluminum. It is fairly lightweight. In fact, I expected it to be heavier than it is based on its size.

The box features four ports and a button on the backside. One is for the power adapter, two are for the stereo RCA hookups, and one is to attach the included antenna. The button triggers the Bluetooth pairing. Other than the backside and the rubber feet and LED light, the box is almost featureless.

The package comes with the antenna, a traditional left-right RCA connector (with RCA on both ends), a digital RCA connector (a 3.5mm digital connector on the one end), and a DC power supply with three international adapters so you can use it with a multitude of speakers in a variety of countries.

Relay DAC 2

Setup and Use

The instructions boast a one-minute setup and that’s no joke. The hardest part about setting up the Relay was pulling out my receiver so I could reach the backside and find an empty slot to plug the RCA connector into. Everything else was slick and easy.

Once everything is connected, which might be a lot easier for you if your stereo is in a more convenient spot than mine, all you have to do is press the power button (also known as the Bluetooth pairing button). When the indicator light turns white, pair it with your iPhone and start playing music.

You don’t have to turn off the Relay when you are done playing music. After 30 minutes of nothing, the device will power down. You can turn off the automatic shutoff feature, but it is convenient because you won’t worry about drawing extra power unnecessarily by having it always on.

The Relay doesn’t work with any specific software. As long as you have Bluetooth, you can use it to play audio through the DAC, whether it is from Spotify, Rdio, Pandora, or Apple Music.

The quality of the Relay makes it stand out from other DACs I’ve tested in the past. There is zero lag and no skips and the level of audio playback is indistinguishable from that of a CD. I tested it. With a CD copy of T-Rex’s Slider in my stereo and the album called up on my iPhone, I switched between the two and literally could not tell the difference.

Because the relay works with any speaker with an AUX input, you can connect it to any stereo in the house. I decided to test its compatibility by connecting it to a 25-year old receiver with 40-year old speakers connected to it. It worked perfectly. And, it was pretty cool to hear music streaming from my iPhone to my vintage 1970s Pioneer CS-66 speakers.

Relay DAC 3

The Good

As noted above, it’s all about the quality of the playback. No matter how good your portable Bluetooth speaker is, it will never be as good as your home stereo speakers and this DAC provides a pitch-perfect replica of CD quality sound. So, streaming music from your iPhone will only be limited by your home sound system.

The Bad

Only one device can be connected to the Relay at a time. It features something called “PartyPairing,” which allows you to quickly pair a new device without having to reset and hit the Bluetooth pairing button. However, the first device has to have Bluetooth turned off before the second device can find the Relay.

Luckily, the Relay also features something called “TurboPairing,” which means the box remembers up to six devices at a time for faster pairing when you switch.

Relay DAC 4


The Relay costs $249. Considering this can be used with any speaker system with an AUX input, you’re really saving a huge amount of money over investing in expensive Bluetooth compatible speakers. This device is incredibly sturdy and will likely last as long as, if not longer than, your home stereo speakers.


If you are concerned at all with the audio quality of digital music and have a nice home stereo setup, this is a golden investment.

What do you think of this hi-fi DAC? Let us know in the comments below.

  • Dom Sad

    I’m using windows AirPlay software to stream music to my HTPC that is connected to Onkyo AV receiver.
    From my experience Bluetooth always downgraded sound quality.

  • Greg S

    AirPlay can stream ALAC (same as CD quality) using wifi. Not quite vinyl analog standard, but better than Bluetooth so far…. Great option above Lori, I’m definitely going to read more.
    The best option I’ve found for storing music on my iPhone is using the ALAC compression for CDS. I’ve ripped all my fav CDs to ALAC and stream from my iPhones or iTunes (PC) to an Apple TV 3 connected to my amp/speakers with digital optical. Does anyone use a different setup to store the best quality music on their iPhone, and stream to there amp?
    One biggish problem is that I can’t use iCloud Music Library as it converts the ALAC files to smaller lower quality files (MP3 I think). And not using iTunes Music Library takes most of the function and fun away Apple Music. Can anyone suggest a work around?

    Also I was thinking about buying the new aTV but there is no optical digital and my amp is old-ish and doesn’t support HDMI. Another quandary.

    • QuarterSwede

      ALAC and any lossless compression is BETTER than Vinyl analog.

    • QuarterSwede

      You can also use an Airport Express. It has optical out in the 3.5mm jack.

      iTunes Match streams song using 256kbos AAC which in A/B tests is indistinguishable from 16-bit CD audio. Anything you think you’re missing is all in your head.

  • Loke1988

    Very interesting indeed! Although I have no use for it at the moment. My iMac is wired via USB through a mini DAC and then RCA’s to my Adcom Klipcsh set up. I can control the action remotely via Apples Remote app. The majority of the files on my iMac are lossless so the sound quality is good if not great. I also have an Airport Express wired to another set of RCA inputs for when I want to stream from my phone for pure convenience and the sound quality is of course downgraded. I’m guessing this device would greatly improve the sound quality over the Express due to it’s on board DAC but since I have a wired set up I couldn’t justify this purchase but I really LOVE the idea.

  • coLin

    BestBuy has Onkyo TX-SR333 5.1-Channel AV Receiver for $150 w/ Bluetooth and Airplay so I think it is better than this imo