Marantz M-CR612 Network CD Receiver

Marantz M-CR612
100% human

When I was a kid, my family’s sound system was what was called an “all in one”. Radio, recording player, cassette: one device for the lot. The Marantz M-CR612 Network CD Receiver could be thought of as the 2019 “all in one”. But oh so much, much better.

Marantz M-CR612 features

To be clear, one way in which it is better is that the Marantz M-CR612 does not come with speakers. There are plenty of devices around with built-in speakers. This unit provides the connectivity and power and audio sources. But it leaves it to you to choose the most personal part of an audio system, the part that most defines the sound. You may already have speakers that you plan to use, or you may want to buy new. Either way, you’re not wasting your money on substandard packaged speakers.

Marantz M-CR612

So, what’s this about “all in one”? Well, the Marantz M-CR612 includes a stereo amplifier to drive those speakers, a CD player for the old silver discs, a USB socket for playback of music from USB storage, and advanced networking capabilities. Oh, and it also has a radio. That is a 2019-appropriate radio, with FM and DAB+.

All that’s in a stylish, compact system. The unit has curved left and right edges to its soft gold façade – black is also available. That has been Marantz’s house-style for the last few years. It stands 111mm tall, 280mm wide and 303mm deep. There are various control keys scattered around the front. Volume is adjusted by buttons rather than a knob. A large cyan-on-black display lets you know what’s going on, showing text about the music that’s playing and so on. The CD tray is above that. The CD player also handles CD-Rs and CD-RWs carrying MP3, AAC or WMA tracks, just in case you still have some good old-fashioned compilation discs.

Marantz M-CR612


Also on the front is a 3.5mm headphone output. I’ll return to that for something I’m sure will be thrilling to geeks.

The main connections are at the back. There are four pairs of speaker outputs: A and B. That’s fairly old-school, being able to connect two pairs of speakers. Either or both can be played back at a time. But there’s more! The headline power output of the unit is 2 x 60 watts (at a very high 10% distortion). More realistically it’s 2 x 50 watts (0.7%). But it turns out that there are four amplifiers, so it’s 4 x 30 watts or 4 x 25 watts, according to taste. Generally, A+B speaker outputs should only used if both pairs of speakers have an impedance of at least 8 ohms. But since they’re independently amplified, that’s not the case here. You can also use the two sets of output to bi-amplify one set of speakers if you’re into such things.

And there’s even more. A third mode is called Parallel BTL, for Bridge Tied Load. That combines two 30-watt amps into one 60-watt amp, realising the full headline output. But in that case, only one set of speakers can be used.

There’s one set of analogue audio inputs via RCA sockets and two optical digital audio. You could use one of those with your TV. There’s also an Ethernet socket and the USB port for connecting storage.

Finally, both dual band Wi-Fi and Bluetooth are built in. A proper F-Type antenna connection is provided to screw-on the included antenna cable. Even in my office, which is swathed in metallic insulation, the unit reported 100% signal quality on DAB+ radio stations.

Marantz M-CR612

Installing the Marantz M-CR612

The first time you plug in the unit and switch it on, it fires up a simple wizard to guide you through setup. There’s not too much to it: selecting interface language then network setup. Radio station tuning happens when you go to the tuner the first time.

When I got to the network bit, rather than unfurling one of my longer Ethernet cables, I decided to go Wi-Fi with the Marantz M-CR12. There are three methods for doing this. The third one is to use the WPS key on your router. The second one is to choose an SSID and key in your network password. I chose the first one: use an iOS device. I opened up an iPad, went to Wi-Fi settings, and chose the Marantz M-CR612 which had appeared in the “Airplay Speaker” section. After maybe twenty seconds, with no further interaction from me, the unit was connected to my home network.

At that point it called in home and found that a new firmware was available. I’m pleased to say that it asked, first, before going to get it. The whole update took about five minutes.

As for the rest, it was just a matter of plugging in the speakers and the power. But you’ll definitely want to install the HEOS app on at least one of your smart devices – Android or iOS, it doesn’t much matter. That’s the best way to do all the network stuff. You can navigate through things with the included IR remote, but it is slower.

Marantz M-CR612


It seems that the HEOS stuff isn’t incorporated into the core firmware but carried separately. I went to the DAB+ tuner first off, just to make sure that the system was working okay. That’s when it scanned the relevant radio bands and tuned in the 21 available stations. After I confirmed sound was coming out (and finding I didn’t much like what ABC Jazz was playing at that moment) I fired up the HEOS app on an iPad. It pretty much instantly informed me that the HEOS app on the iPad needed to be updated. I told it to go ahead … and the DAB+ music stopped. The front panel display of the Marantz M-CR612 told me that it was updating its HEOS software. When that was done after a minute or so, the app came back and invited me to go to the App Store to update it. Which I did, and then all was ready to go.

HEOS started as a separate company. Indeed, the technology was largely developed in Australia. But it was always closely connected with the parent company of Denon and Marantz, now Sound United. In one sense, HEOS is just another multiroom audio system, except that it has a wider range of products than most. That’s because in addition to HEOS branded speakers and devices, all Denon and Marantz network-capable devices also support it. So, with HEOS your multiroom system may have a compact HEOS speaker in one room and a massive 150-watt-per-channel, eleven-channel Denon home theatre receiver in another and a nifty compact all-in-one Marantz M-CR612 in a third.

HEOS app
HEOS app, streaming music from network server

Sharing inputs

But HEOS also has one feature which, I’m fairly sure, remains unique to it. That feature lets you play any source connected to any HEOS device to any other speaker or zone. Right now I am listening to The Steve Miller Band’s album Abracadabra from a 35-year-old vinyl recording through the Marantz M-CR612.

But, you might say, the Marantz doesn’t have phono inputs, does it? No, it doesn’t. Nor does my turntable have a built-in phono pre-amplifier … er, hang on a moment. Vinyl being what it is, that album finished. Now Cha by Jo-Jo Zep and the Falcons is playing. Try finding that on Spotify or TIDAL. Anyway, no, my turntable doesn’t have a phono pre-amp (I do own a couple, but I’m not using them). No, the turntable is plugged into a Denon home theatre receiver which does have a phono input. And it also works with HEOS. So, the Denon is sending the music across the network to the Marantz unit.

The connection turned out to be a little flaky with the Marantz M-CR612 connected wirelessly. It was probably due to the thick soup of 2.4GHz and 5GHz signals with which my office is filled. I plugged the Marantz into Ethernet and it worked perfectly.

HEOS app
With HEOS you can pick inputs from any connected device

Talking to the Marantz M-CR612

HEOS stuff, and therefore the Marantz M-CR612, is controllable by voice using both Alexa and Google Assistant. You can do things like skip tracks, switch the unit on and off, increase and lower the volume or mute the unit. You can tell it to play music from some Internet services.

In both cases, you’ll need to jump through the system hoops of enabling HEOS control for Alexa or Google Assistant. The former had me bamboozled for a while because Alexa wasn’t objecting to most commands, but neither was she doing anything in response. It turned out that I’d previously associated a different Marantz device with her and its name lingered on. Alexa was interpreting the commands as intended for it.

So, it was just a matter of updating the devices and then she started working properly. The functionality for Alexa and Google Assistant was much the same. You can do things like set to volume to an absolute level by number or increase or lower it. “Alexa, turn up the volume on Marantz” increased it by five decibels.

HEOS app
… including, of course, a turntable

Streaming music by voice

Oddly, neither Alexa nor Google Assistant would play Spotify content to the unit, even though it is Spotify Connect-capable, and even though the unit appears in the list of speakers in the Spotify app on my phone as a speaker to which I can send Spotify sound. HEOS-equipped devices were recently given the ability to play Spotify without a premium subscription, so I guess it’s possible that there are bugs associated with that change.

The Marantz M-CR612 is not equipped with microphones so it can’t hear you. You need to have some Alexa (or Google Assistant) device handy to speak to in order to make it do things. I have an Echo Dot (and Google Home Mini) in my office for the purpose.


The Marantz M-CR612 was a delight to use. It worked quickly and well with network music from my server – both using the HEOS app and using my usual DLNA app. It worked well with streaming music, including TIDAL and Spotify. I plugged in a large portable hard drive carrying a duplicate of all my music and found it easy to navigate through its contents for playback using the HEOS app. It played back most of my high-resolution stuff, including 24 bit, 192kHz FLAC files, Direct Stream Digital and DSD128.

And of course, it played back my CDs.

I used it with a pair of KEF R300 loudspeakers. They are largish bookshelf-sized models with very competent bass down to 40 hertz. They sounded brilliant, especially when I advanced the volume to room-filling levels. There was plenty of power to drive them.

Subwoofer and headphones

There is a subwoofer output, although this wasn’t configurable so I figure that it wouldn’t stop bass going to the main speakers. There are also line level outputs – you can set their output level to “fixed” if you want – so you can either add your own amplifier or active speakers, or just use the unit as a source for some other audio system.

I measured the 3.5mm headphone output. It’s capable of delivering almost 100mW undistorted into highish impedance (300 ohm) headphones, and 55mW into lowish (16 ohm) headphones. Both of those will provide more than ample levels for almost all headphones and earphones. However, the output impedance of the headphone connection was around 75 ohms. For technical reasons we won’t go into here, that will affect the frequency balance of some headphones. Which ones and how much? That’s the big unknown because the information about headphones needed to assess that is rarely published.

While I prefer to see headphone output impedances to be two ohms or less, I will note that Marantz has reduced this figure markedly of late. Some of its recent devices had output impedances of 450 or more ohms, which is much more problematic.


The Marantz M-CR612 is a mature and highly effective all-in-one playback system for 2019. And one with unexpectedly advance features, such as voice control (so long as you have a suitable Alexa or Google Assistant device to talk to) and multiroom support. If you want a neat, effective and fine sounding system, check it out.

The Australian website for the Marantz M-CR612 is here.

Value for money
Ease of Use
Reader Rating10 Votes
Quality sound
Flexible HEOS multiroom support
Alexa and Google Assistant support