ABQMD

Sorry for the cross-post, but if the shoe fits... FYI, Catalina breaks Roon's local file access if you have your music files on an external disk. My iMacPro has a thunderbolt-connected Akitio 4 disk array as JBOD and Roon cannot access the music folder on one of the disks. I get an "Error loading folder Unauthorized" message when I try to designate the Music folder. Roon is aware of the issue and is working on it and advises not to update to Catalina. Streaming still works fine in Roon with both Tidal and Qobuz. https://community.roonlabs.com/t/roon-core-macos-catalina/79920

FYI, Catalina breaks Roon's local file access if you have your music files on an external disk. My iMacPro has a thunderbolt-connected Akitio 4 disk array as JBOD and Roon cannot access the music folder on one of the disks. I get an "Error loading folder Unauthorized" message when I try to designate the Music folder. Roon is aware of the issue and is working on it and advises not to update to Catalina. Streaming still works fine in Roon with both Tidal and Qobuz. https://community.roonlabs.com/t/roon-core-macos-catalina/79920

FWIW, both the Topping D50 and DX7s easily do DSD256 on my iMacPro and in HQP NAA on an older Mac Mini (2009) in macOS. With Linux on the Mac Mini, it can nicely do DSD512 as HQP NAA pushed by the iMacPro core. Both Toppings support 705.6/768k rates.

From what I read, Apple's continued use of fusion drives in the new iMacs eliminates the T2 chip possibility.

All is OK. Figured out how to change and save the grub config so all is fine now.

It's a 3.2GHz 8-core Intel Xeon W processor, Turbo Boost up to 4.2GHz, 19MB cache. I do have Multicore DSP set to grayed and auto rate family enabled, but will try it enabled too. So the last thing is to figure out how to edit and save the boot config so it automatically boot into the custom kernel. On my setup, the custom core is #5 on the option list for the kernels. Any help would be appreciated!

I do already have your custom kernel installed: linux-image-4.14.99-jl+_6_amd64.deb How do I get to the grub boot loader menu: before or after Ubuntu boots? Edit: OK, I have booted into your custom kernel and it allows me to choose DSD without the DoP setting enabled. However I get distorted sound via DSD512 (fine in DSD256) if I use the poly-sinc-xtr filter. If I use the poly-sinc-xtr-2s filter, it works great. I would have thought the iMacPro could handle the xtr filter without the 2s addition. What do you think, Miska?

I do already have your custom kernel installed: linux-image-4.14.99-jl+_6_amd64.deb How do I get to the grub boot loader menu: before or after Ubuntu boots?

I have Ubuntu Server 18.04.2 successfully running via USB flash drive on my Mac Mini 3,1 (2009) with NAA 3.5.6 bionic running on it. I am running Roon Core on my iMacPro with HQP Desktop 3.25.3. I can see the NAA via IPV6 and IPV4. I have a Topping D50 connected via USB to the Mac Mini but I can't seem to be able to upsample PCM to DSD512. I can get playback at DSD256, but only if I enable SDM pack to DoP. However I thought I wouldn't need/use DoP in a Linix-based NAA. If I don't enable SDM pack in my preferences, I don't get DSD at all on playback as an option. What am I missing? The Topping D50 is listed as being able to play DSD512 native, so I don't know if it is my settings that are limiting DSD512 or the DAC.

Since I also have a iMac Pro and haven't been able to test how it works with native DSD512, I am highly interested in your experience. In HQPlayer, which filter and modulator are you using, and what is the CPU load on the iMac Pro when you run DSD512? For me, running HQPlayer on the iMac Pro upsampling to DSD256 via DOP and using poly-sinc-xtr, the iMac CPU is at ~25-30% with no stuttering/dropouts.

OK! I will stop messing with VMs and get back to work on a Linux install for NAA on my Mac Mini. Muchas gracias, Miska.

One more question: would NAA work in a Linux VM in Parallels on a Mac, or would the Linux OS need to be direct installed?

I tried the NAA in a Parallels Windows 10 VM (didn't work for either a Windows 8.1 or 10 VM) on a Mac Mini. I run HQPlayer on an iMacPro and I'd like to keep it there since it is a processing powerhouse and dead quiet. Still trying to figure out how to get to DSD512 via NAA on my Mac Mini. I could try Windows 10 in Boot Camp instead of via Parallels VM. Would that work for NAA? I've still had no luck trying to figure out how to run Linux on the Mac Mini so I could use it for NAA.

Will NAA work on a Windows 10 VM via parallels?