Marantz NR1510 DAC Function with Bluetooth

[Ronman45]

I just purchased a Marantz NR1510 and have a question regarding its internal DAC - When I am streaming songs from my iPhone via bluetooth, Is the DAC in the receiver actually functioning or is it bypassed? I have the receiver configured for stereo listening (2.1). I use the receiver out in my small shop paired with a Marantz MM7025 amp feeding a pair of Klipsch R-50M bookshelf speakers and supplement the low end with a Martin Logan Dynamo 600 sub. I'm happy with the sound quality but wondering if using my Dragonfly Red and a 1/8 inch stereo to RCA male stereo cable plugged into the CD input on the back of the receiver will noticeably improve audio quality if in fact the aforementioned DAC in the Marantz is bypassed. The manual is no help. If anyone familiar with Marantz gear knows, thanks in advance.

 

[everettT]

I just purchased a Marantz NR1510 and have a question regarding its internal DAC - When I am streaming songs from my iPhone via bluetooth, Is the DAC in the receiver actually functioning or is it bypassed? I have the receiver configured for stereo listening (2.1). I use the receiver out in my small shop paired with a Marantz MM7025 amp feeding a pair of Klipsch R-50M bookshelf speakers and supplement the low end with a Martin Logan Dynamo 600 sub. I'm happy with the sound quality but wondering if using my Dragonfly Red and a 1/8 inch stereo to RCA male stereo cable plugged into the CD input on the back of the receiver will noticeably improve audio quality if in fact the aforementioned DAC in the Marantz is bypassed. The manual is no help. If anyone familiar with Marantz gear knows, thanks in advance.

Yes, the DAC is always functioning (some caveats apply) unless your feeding your speakers a digital and then the speakers would have a DAC. Using any connection to the AVR other then Bluetooth will yield better sound, the question is will you hear the difference? I know I can but I don't use Bluetooth except for rare instances.

If your in your home, Wi-Fi should be your first "non connected" choice.

 

[viorelc]

When sending signal over Bluetooth, the signal is sent in digital format, in a codec that’s supported by both source device (iPhone) and receiver. I believe newer tech accepts AptX, but you’d have to check actual specs of your devices. Based on that negotiation, the source applies a conversion (still digital) to compress the digital signal to make it fit to the negotiated codec and bitrate. Once the (possibly resampled) signal is at the receiver, the receiver uses its own DAC to convert the digital signal into analog and play it. Hope this helps.

 

[lovinthehd]

I doubt you'd hear a difference by using the external dac, but you can plug it into an analog input and use the direct modes to avoid further processing by the avr if you want to try (but may lose the sub without using LFE+Main mode). I'd use wifi over BT, and many streaming services have a direct connection over the internet (like Spotify Connect for example, built into your avr), just using your phone/tablet as a remote of sorts.

 

[BoredSysAdmin]

When sending signal over Bluetooth, the signal is sent in digital format, in a codec that’s supported by both source device (iPhone) and receiver. I believe newer tech accepts AptX, but you’d have to check actual specs of your devices. Based on that negotiation, the source applies a conversion (still digital) to compress the digital signal to make it fit to the negotiated codec and bitrate. Once the (possibly resampled) signal is at the receiver, the receiver uses its own DAC to convert the digital signal into analog and play it. Hope this helps.

iPhones don't do AptX at all. AptX is Qualcomm's tech, and Apple would instead not get involved with Qualcomm more than necessary and looking to move away from them asap.
Unfortunately, apple devices support only BT SBC, with the proprietary implementation of AAC codec, per my small research, is supported over BT by Apple's hardware. The bottom line is BT, especially with Apple devices, isn't the ideal way for wireless audio streaming. You'd be better of using lossless Airplay with supported Airplay player, like AppleTV.
Here are a few articles listing some the AirPlay-compatible devices:

List of AirPlay 2-compatible TVs (2024 updated) - iGeeksBlog

Isn’t everything better when it’s on a bigger screen? Thankfully, most leading TV manufacturers incorporate AirPlay 2 support, allowing effortless content sharing and mirroring from your iPhone, iPad, and Mac to your TV. But is your TV AirPlay 2-compatible? Can you seamlessly stream movies, home...

www.igeeksblog.com

How Do You Use AirPlay to Stream Digital Music?

With Apple's AirPlay proprietary technology, you can stream documents to a printer, music to speakers, videos to a TV, and a whole lot more.

www.lifewire.com

There are also receivers that support AirPlay natively. Here are some of them:

The Best AirPlay Receivers

Listen to your favorite music or stream movies from your iOS or macOS devices easily with an AirPlay receiver.

www.makeuseof.com

Using Marantz DAC vs. an external DAC would make the least difference in sound quality or even worse.

 

[Trebdp83]

If wifi is in reach of the devices in the shop, just Airplay directly to the Marantz from the iPhone. This will give you lossless audio up to 24/44.1 or perhaps 24/48, though not bit perfect output for those concerned with such things. If you want 24/192 hi-res from Apple Music, you will need an external DAC connected to the iPhone and then into the Marantz. I believe the Dragon Fly Red is limited to 24/96.

 

[BoredSysAdmin]

I didn't check before, but yes, Marantz NR1510 does support AirPlay - OP should use it instead of BT

 

[Ronman45]

My sincere thanks to all who responded. I do have wifi out in the shop and I should have specified I am using the AirPlay function, which I see verified on the cheap flat-screen TV I have out there. I really enjoy reading threads on this forum now that I'm retired and have the time.
Have a Great Weekend!