Meridian Extension with 818v3 and dCS NWB

Tinkering Roon API
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if you install tailscale, you can invite me and ill just use tailscale ssh to get in. easy and no weirdo network stuff

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I have tailscale installed. How do I invite you?

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I feel like a bit of an idiot, but I’m running an 818v3 together with several 218 zone controllers for other rooms, and have never heard of a meridian extension or what it would provide for. Can anyone clue me in? Many thanks. Jay

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The 218 is Roon Ready and speaks Meridian’s proprietary speakerlink/comms protocol to the 818v3. So Roon tells the 218 to change the volume because it is Roon Ready, and it tells the 818v3 to change the volume because it speaks Meridian’s comms protocol (over speakerlink I’m guessing).

@Ludwig is using a dCS network bridge as his Roon Ready endpoint and is probably feeding a SPDIF signal from that to his 818v3. That SPDIF only carries audio data and no 2-way communication about the volume/standby/source info. He needs his Roon to somehow control the 818v3’s volume.

I am in the same situation as @Ludwig, but I’m using a Raspberry Pi 3 with some audio HAT instead of the 218, and I’m directly into DSP8000XE with no 818v3 in the middle. I need Roon to tell the DSP8000XE to change the volume – and that path doesn’t exist.

So instead, we are using the RS232 (serial port) connection on the 818v3 / DSP8000XE to control the volume/standby/source – but something has to speak RS232 Meridian protocols (which change from product to product). That’s what the extension does.

I would actually stop using my extension if my Meridian 210 were working. Unfortunately, it’s a broken pre-beta unit, and they haven’t sent me a new one yet. Not a huge deal because my solution works fine, but it’d be nice to let my friends come over and use Spotify to talk to it.

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I’m all set and it’s a big relief. Finally I can use my main zone as easily as the others, and seamlessly.

What I did was:

  • bought the strongest RPi that was easy to get. (The advice about which would work was somewhat shady, and I can’t improve on that, I’m afraid.)
  • bought USB-Serial adapter cable (chipset pl2303, which works - at least one member of the Roon team uses it too.)
  • bought Serial Null Modem Cable. (All the problems I had with getting the RPi to talk to the Meridian were caused by picking up a random cable from my basement and not realising it was a straight-through Serial cable, not a Null Modem one.) Watch the genders too, you might end up frustrated otherwise.
  • Install DietPi (32 bit) on the RPi. There you can easily install the Roon Extensions Manager. From then on setup is in Roon. You can find and install the Meridian Roon Extension within Roon, and set it up. (The version of Extensions Manager in 64 bit DIetPi doesn’t include the Meridian Extension, although @Danny was puzzled by this.)

What works:

  • Automatic input switching on the 818 when you start a track to the zone.
  • Volume (not perfect: see below)
  • In and out of Standby
  • Mute

What doesn’t work and should:

  • Volume doesn’t always agree between the Meridian device and Roon. If you punch many times the + or waggle the slider around, you can make it go wrong quite easily. I wonder if there’s a more reliable way of getting this information. It feels like the extension isn’t checking the Meridian state but just assuming it follows the commands Roon sends it (maybe performance reasons?)
  • Volume doesn’t always agree sometimes in a dramatically loud way. I haven’t found a way to reproduce it yet but it’s happened a good few times, and 8KSE can go LOUD…
  • I can’t press play or pause or use any other transport controls on the 818 front panel. This is a missed opportunity and was there in the ID41 support. Maybe @Danny could look at this?

Other suggestions:

  • There are a load of other commands which can be accessed. A few cm of extension of the Volume control panel would fit them. Most interesting would be these:
    • changing Absolute Phase (PH)
    • Balance (ML MP MM)
    • Axis (AP3CFE/03)
    • EBA (AP5000/01)

Thanks Danny for this extension.

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I know of no way to get this info out of the Meridian boxes :frowning: If I could get a command over rs232 that “play was pressed”, i could totally tell Roon to play.

This is wrong. It means something is goofy with your extension setup. The data should flow both ways and it should be rock solid. Try this out… if you use the MSR only, does it stay in sync in Roon? If you use Roon’s +/- only, does it stay in sync with the device?

again, it should be rock solid and in sync. if it isn’t, that means you have an issue with the extensions speaking the protocol. there are multiple protocols meridian has here, so it can require some tweaks.

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Very interesting thread much useful information. Thanks

I have one Meridian DSP5200HC and nothing else meridian - I do have an Allo DigiOne Signature (inc RPi4 4GB) and a Nucleus+ as Roon core.

Does anyone know if I can play music out through this speaker and control the volume of course?