#+TITLE: Schiit Magni 3 headphone Amp, Modi 3 DAC with Apple Lightning Dock
#+SUBTITLE: With iOS Neutron Music Player
#+DESCRIPTION: Tutorial on how to setup a bit-perfect headhphone stand
#+KEYWORDS: schiit magni modi apple ios lightning dock neutron
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* The setup
This is a tutorial on how to setup a bit-perfect headhphone stand that is
both cost effective and performant.

** Philosophy

- Write article how you setup your offline music collection.
- Hardware, player software, tagging, streaming... Similar to [[https://lobste.rs/s/ezmsab/prepper_style_music_hoarding][this]].
- Start with theory: why self-hosted
- Stack as per [[https://www.reddit.com/r/headphones/comments/ark7y2/schiit_stack_to_iphone/][this]].
- You need separate powersource for apple dock.
- Then, download your flac tunes in iphone and [[https://apps.apple.com/gb/app/onkyo-hf-player-hi-res-music/id704139896][install Onkyo player pro]], 10€ (see if there's a free try out before).
- Inspect with the player your file sample rate: "original sample rate of
  the audio file and the actual rate being played." [[https://www.whathifi.com/us/advice/how-to-play-hi-res-music-your-iphone-0][Source]].
- But having 192-kHz/24-bit FLAC files doesn't really matter:
  "Unfortunately, there is no point to distributing music in 24-bit/192kHz
  format. Its playback fidelity is slightly inferior to 16/44.1 or 16/48, and
  it takes up 6 times the space." [[https://people.xiph.org/~xiphmont/demo/neil-young.html#toc_1ch][Source]].
- Document to schiit article, and mention hardware cahnges first under philosophy. Reason? Formulate it as in [[https://darko.audio/2020/06/a-hi-fi-for-your-spotify-or-apple-music-or-amazon-music/][here]] under philosophy.
** Hardware

If you want to play hi-res music you are currently limited by the DACs inside iPhones.

iPhone DACs can at maximum play music files of 24-bit/48 kHz and if you
try to play anything higher resolution, say, flac files you've downloaded from
various streaming services, your 24-bit/96 kHz and 24-bit/192 kHz tunes (or
what have you), iPhone will just downsample them to 24-bit/48 kHz.

If you want to listen to anything higher than 24-bit/48 kHz, you'd need to
connect your iPhone to an external DAC.

#+BEGIN_QUOTE
DACs are built into Apple devices like the iPhone, but they are only
mid-range DACs that max out at 24 bit at 48 kHz. Apple's Lightning to 3.5 mm
Headphone Jack Adapter has a DAC, but it likely maxes out at the same bit
depth and sample rate. Some Lightning and USB headphones have DACs, but
again, they likely won't get you Hi-Res compatibility. That's why a
higher-quality DAC is needed.[fn:1]
#+END_QUOTE
** Software
Music is stored on an external HDDs operated by OMV and accessed by Neutron
over Wireguard. See
[[https://pyyhttu.kapsi.fi/debian/openmediavault/omv.html][omv.html]] and
[[https://pyyhttu.kapsi.fi/debian/pi-hole/pihole.html][pihole.html]] for more
info.

*** NEXT Setup OMV HDDs over non-usb connection to avoid Neutron timing output
It seems to be connectivity through USB [[https://neutroncode.com/forum/viewtopic.php?f=3&t=6922&p=20046&hilit=problems+with+ftp&sid=c4da17e7bdd52d63f15208a624efa5a7#p20044][may cause problems.]]
** Music

I have music in multiple samplerates which I want to listen to as they are.
So do have any files higher than 24-bit/48 Khz?

I ran a query against my music library in Beets to see:

~$ beet list -f '${samplerate}' > samplerate.txt~

#+BEGIN_SRC bash
44100
48000
88200
96000
176400
192000
#+END_SRC

Yes, I do.

44kHz and 48kHz are what
[[https://www.head-fi.org/threads/what-samplerate-is-most-popular-here.826328/][every
other samplerate builds on]], so 44100, 88200, 176400, 352800 are all
multiples of 44100hz, so if you have music in these samplerates (or its
multiples), it is basically 44100. Same thing with 48000: 96000, 192000,
384000, 768000... it is basically 48000.

What about bitdepth?

~$ beet list -f '${bitdepth}' > bitdepth.txt~

#+BEGIN_SRC
16
24
#+END_SRC

As everything I have is in flacs, those are the two bitdepths returned. No
128, 192, 256, 320 kbps mp3s, or 1 bit DSDs. Just flacs.

I picked one of each above 49kHz to test with if I can get them to play with
iPhone and via external DAC.

~$ beet list -p 'samplerate:88000..'~ (so basically 44 kHz)

#+BEGIN_SRC
Anubis - 2020 Homeless
media: CD
bitdepth: 24
samplerate: 88200
#+END_SRC

~$ beet list -p 'samplerate:96000..'~ (so basically 48 kHz)

#+BEGIN_SRC
Cosmograf - 2021 Mind Over Depth
media: Digital Media
bitdepth: 24
samplerate: 96000
#+END_SRC

~$ beet list -p 'samplerate:176400..'~ (so basically 44 kHz)

#+BEGIN_SRC
Procol Harum - 2017 Novum
media: CD
bitdepth: 24
samplerate: 176400
#+END_SRC

~$ beet list -p 'samplerate:192000..'~ (so basically 48 kHz)

#+BEGIN_SRC
MONO - 2006 You Are There
media: CD
bitdepth: 24
samplerate: 192000
#+END_SRC

Order from

Magni 3+ headphone AMP and PREAMP (SKU: ARTMGN3+-Silver)

Modi 3 - AFFORDABLE DO-ALL DACS (SKU: ARTNMD3-Silver)

- Alternative players, should have webdav (nextcloud) shows audio rate:
  Neutron, Hibymusic, Onkyo
- "The iPhone will natively output data up to 24/48 through the Lightning
  port... and hi-res output is possible but for this the iPhone needs
  *software* like the Onkyo HF Player app, which overcomes the 24/48 limit.
  (There are loads of forum threads about that piece of software.)" Source: https://forums.stevehoffman.tv/threads/best-cost-effective-way-to-incorporate-iphone-7-into-stereo-system.888944/#post-22313773
- Modi 3's light lit when it was connected to its own power source (5V / 1A),
  and apple dock with lightgning cable to its own (2,1 A) <-- 1A also might
  be enough:
  https://www.head-fi.org/threads/modi-2-magni-2-connection-issues.853957/
- After plugging in lightning cable to phone and modi 3 and waiting a few
  seconds, a firmware update was received (had to go to settings too for it
  start over-the-air update:
  http://www.3u.com/news/articles/1886/apples-lightning-to-usb3-camera-adapter-gets-a-firmware-update-to-version1.0.5)

*** NEXT iPhone 13 Mini not charging nor connecting

I get the following error popup with Camera Adapter (Model A1619) and Lightning Dock
(Model A1717) combo:

#+BEGIN_SRC bash
Accessory not supported

This accessory is not supported by this device
#+END_SRC

The problematic component seems to be the Lightning Dock stand as solely with
Camera Adapter both connectivity and charging works.

Do I pass enough power?

Tested so far with these [[https://support.apple.com/fi-fi/HT210133][Apple
chargers:]]

- [X] Model A1400 (5W power unit):  Input 100-240V ~ 50-60Hz 0.15A, Output 5V 1A (tested)
- [X] Model A1357 (10W power unit): Input 100-240V ~ 50-60Hz 0.45A, Output 5.1V 2.1A (tested)
- [-] Model A1401 (12W power unit): Input 100-240V ~ 50-60Hz 0.5A, Output 5.2V 2.4A
- [-] Model A1720 (18W power unit): Input 100-240V ~ 50-60Hz 0.5A, Output 5V
  3A OR 9V 2A (supports iPhone 8 and newer fast charging)
- [-] Model A2305 (20W power unit): Input 100-240V ~ 50-60Hz 0.5A, Output 5V 3A tai 9V 2.22A

Test next with 12W power unit, and see if tricks here work: https://discussions.apple.com/thread/253014702

Otherwise test if passing signal solely through camera adapter is
enough for high res sound (confirm with Onkyo, Hibymusic or Neutron) and
compare results to iPhone 8, which does work & charges with camera
adapter/lightning dock combo.

** Neutron player

- [[https://avplus.fi/kokeilussa-neutron-music-player-toisto-ohjelma-ja-neutralizer-kalibrointisovellus-toistoa-tositarkoituksella/][Review of Neutron]].
- Document and enable
  [[https://neutroncode.com/faq/38-bit-perfect-output][bit-perfect audio in
  Neutron player]] as well as
  [[https://neutroncode.com/forum/viewtopic.php?t=6598&p=18298#p18298][these
  settings]] to enable bit-perfect audio. Another document on [[https://neutroncode.com/forum/viewtopic.php?f=3&t=6529&sid=c6216f3b95cd453087a31e83f55711be][bit-perfect settings.]]
- High-res audio is available when [[https://neutroncode.com/forum/viewtopic.php?t=6777&p=19294#p19294][frequencies]] are above 44khz.
- Setup equalizer settings in Neutron as per https://autoeq.app/ for
  Sennheiser HD 650. https://www.reddit.com/r/oratory1990/wiki/index/faq/#wiki_how_is_this_list_different_to_the_github_.2F_autoeq.3F
*** Settings in Neutron

Settings - Playback - DS Effect - Frequency Response Correction (On) - Sennheiser HD 650 (Crinacle, Ears-711). See: https://neutroncode.com/forum/viewtopic.php?f=3&t=6134&sid=741112d452f86455a3143e214d3b051e#p16249
Settings - Playback - Equalizer Presets - 4-Band Parametric (Default) - Device - "USB: Schiit Modi 3": On (The "4-Band Parametric (Default)" can't be disabled, so leaving it on with "USB: Schiit Modi 3" selected).
Settings - Playback - Replay Gain: 'Album' If Whole Album (Replay gain is applied, only if this is defined in tags. If set, Neutron displays on top of main screen the +-db change, usually by lowering it).
Settings - Playback: 64-Bit Processing (After setting this, Settings - Audio Hardware: Bits changes from 32 to 64).
Settings - Playback - Resampling: Audiophile (After setting this, Yes - Owner of the Lonely Heart  over NFS starts cracking on iPhone 14 at 0:00. At 1:14 the cracking is over, and starting over the song, cracking has disappeared. Could be buffering issue. Edit: on exiting Neutron, unhooking the usb, waiting 30 min, rehooking usb, and relaunching Neutron, the playback is choppy again. Pressing pause and waiting 30 min resolves the issue. This is definetely network issue. Play around with network settings next to experiment how to cut down the choppiness.).
Settings - Profile - Bit-perfect (Device, Digital USB, Digital: UPnp/DLNA, Chromecast) - Device: "USB: Schiit Modi 3"
Settings - Profile - Bit-perfect - "Digital: USB:" On
Settings - Profile - Bit-perfect - "UPnp/DLNA, Chromecast:" On (this is dubious if needed, but needed for bit-perfect on iOS, according to this: https://neutroncode.com/forum/viewtopic.php?f=3&t=6435&hilit=usb+lightning&sid=92e881431fa443af28fb27590ac7f64c&start=10#p17499
Settings - Audio Hardware - Follow Source Frequency: On
** Set up streaming to outside with mpd and snapcast

- https://www.reddit.com/r/selfhosted/comments/hiy7gs/guide_to_using_mpd_for_whole_house_audio_and/
- Or, setup on NAS on rpi4 [[https://mstream.io/][mStream]] which is able to
  stream FLACs.
- Third option is to setup navidrome whic has good development and rep according to this thread: https://github.com/beetbox/beets/discussions/4760
and it has multiple compliant iOS clients to choose from: play:sub, amperfy and substreamer.
** Pre-installation tasks
*** DONE Download "Intermod Tests" samples from this page on iphone and listen.
* Footnotes
[fn:1]
[[https://ios.gadgethacks.com/how-to/you-need-dac-enjoy-apple-musics-hi-res-lossless-audio-here-are-best-options-0384656/][Gadgethacks article]] that elaborates on this.