[CarPC]

Hi All --

I want to put what amounts to a home-theatre PC in my 1982 Dodge Van, running Kodi under Windows 7 on a 7-inch 1024 x 600 touch screen.

For now, I will concentrate on audio playback, but eventually I will incorporate other functions (video playback, radio and TV tuners, WiFi internet access, and so on).

I would appreciate feedback from the membership here about the best way to go about this.

When it comes to audio, the way you maximize sound quality is to get the best speakers you can afford, and tailor the rest of the system to them.

Short of sound-deadening the vehicle (just not practical in this case), the most effective way to improve sound quality from that baseline is digital “room” correction (DRC). In this case, the “room” is the interior of the vehicle.

Windows apparently has built-in DRC, but depending on installed audio hardware, some people report that they can’t access the built-in DRC.

Here is the hardware I have in mind:

mobo: ASRockQ1900-ITX mini-ITX
cpu: Intel J1900 2 GHz Quad Core Celeron 10 Watts
ram: G.Skill 2 x 4GB DDR3-1333
ssd: Patriot 2.5" 60GB SATA-3 (system)
ssd: ADATA 2.5" 256GB SATA-3 (media)
dvd: LG GT80N 8x DVD 24x CD Slim SATA

The audio codec on the motherboard is a Realtek ALC892, which is good enough for me.

So, what do you all think? How can I get all this working together smoothly with minimum headaches?

[Ned Scott]

If you're feeling adventurous, try a nightly build (wiki). The latest bleeding edge version of Kodi has just added internal DSP add-on support. We don't have much documentation on what's currently available or all of the settings, but like I said, if you're feeling adventurous... :)

[CarPC]

If you're feeling adventurous, try a nightly build (wiki). The latest bleeding edge version of Kodi has just added internal DSP add-on support. We don't have much documentation on what's currently available or all of the settings, but like I said, if you're feeling adventurous...

I guess you mean the Windows audio DSP build. Yes, this looks very exciting, but according to wisler (http://forum.kodi.tv/showthread.php?tid=226499) it only supports the confluence skin right now, and I think I'm going to need the re-Touched skin for my application.

Thanks for pointing me to the wiki, though (I don't know how I missed it). It looks like there is a lot of "getting started" information over there that may just be what I need right now.

[k4sh1n]

Please, please, pretty please, showcase your build in the "Hardware Showcase" thread section.

I would be ever so appreciative if you do

[BatterPudding]

As a new project there are so many sub-tangents you'll have to chase. The most obvious one to me is the state of your audio files. There is no point in posh speakers if you are only using MP3. So you have that rolling scale of how good your hearing and budget is. Will MP3 and average speakers be "good enough" for out on the road? Or are you going for full on audio quality of lossless FLAC and top quality audio system - which then has the down side that it is more likely to get nicked.

Personally I just have a bog standard KODI v15 setup. Connected to an Onkyo TX-SR806 AV amp via a digital cable. That comes from an old Realtek onboard audio. Sounds pretty decent - Dark Side Of The Moon sounds as clear as the original CD.

[CarPC]

Please, please, pretty please, showcase your build in the "Hardware Showcase" thread section.

I would be ever so appreciative if you do

I'll be glad to. Parts are on order now, but the fabrication of custom mounting brackets and such will take a little time.

When I have something to show, I'll start a thread on it and PM you.

[CarPC]

As a new project there are so many sub-tangents you'll have to chase. The most obvious one to me is the state of your audio files. There is no point in posh speakers if you are only using MP3. So you have that rolling scale of how good your hearing and budget is. Will MP3 and average speakers be "good enough" for out on the road? Or are you going for full on audio quality of lossless FLAC and top quality audio system - which then has the down side that it is more likely to get nicked.

Personally I just have a bog standard KODI v15 setup. Connected to an Onkyo TX-SR806 AV amp via a digital cable. That comes from an old Realtek onboard audio. Sounds pretty decent - Dark Side Of The Moon sounds as clear as the original CD.

Yes, you are so right!

My audio files are all 254 kbps AAC encoded. I can't tell the difference between that and CD-quality sound on any stereo I have access to, including high-end gear at pro audio shops, where I bring my own USB stick for listening tests. On a good stereo, I think I can hear a slight difference between 160 and 254 kbps, but I wouldn't bet my life on it. I can definitely hear the difference between 126 and 160 kbps, though, on just about any stereo.

I most definitely cannot tell the difference between CD-quality (16 bit, 44.1 ksps) and any of the higher-definition formats, which are only useful for professional recording and mixing.

Nor can I tell the difference between a tube amp and a solid state amp, except in the case of a class AB output stage that's being over-driven to the point where harmonic distortion becomes audible.

I cannot hear anything above 10 or 12 KHz, so a 24KHz cut-off frequency is plenty. And no, frequencies above that cannot contribute to the perceived timbre of a sound.

On the low end, I definitely can hear the difference between a system that cuts off at 40 Hz and one that goes all the way down to 20 Hz. Below that, I don't know, but I doubt it.

The quietest room in my house is my bedroom, but even in there I cannot hear the difference between attenuating a signal by 66 db and muting it completely. In a car, the noise floor is quite a bit higher.

I cannot hear less than a 0.5 db change in volume.

Given all that, the quality (dynamic range, signal-to-noise ratio, distortion) of the on-board codec are more than good enough. With the right choice of speakers and power amps, the latency and phase linearity of the DSP path will be far more important to sound quality than anything else I have control over.

That TX-SR806 of yours is a very nice unit, by the way. I think you would have to spend three to five thousand bucks on speakers before it made any sense to spend any more on a receiver.

[CarPC]

At this point, my first priority is making a car stereo head unit out of a mini-ITX PC.

Can Kodi be configured to do this?

I must admit, the more I read the FAQs, the more confused I get.

I've been using Windows Explorer and MPC-HC on my desktop PC to play the 254 kbps AAC audio tracks of MP4's downloaded from YouTube. This is the extent of my experience using digital media players (even though I write real-time code for a living, including embedded kernels, device drivers, audio codecs, etc. in C and assembler).

So... while driving down the road, the driver needs to adjust the volume, tune the radio, navigate the directory structure to pick a song, album, or playlist, turn shuffle on and off, and so on. The user interface elements must be big enough to be seen out of the corner of the driver's eye and simple enough to be operated with one finger, without taking his attention off the road.

File browser, media player, signal conditioning. Text so large that maybe three lines of a directory tree, with album cover art, is all that would fit on the 7-inch screen. That's all I want for now.

I thought Kodi with the re-Touched skin could provide this, or at least act as a skeleton on which I could hang the rest of the functionality.

Am I wrong?

If so, what applications and/or utilities should I be considering?

[k4sh1n]

Please, please, pretty please, showcase your build in the "Hardware Showcase" thread section.

I would be ever so appreciative if you do

I'll be glad to. Parts are on order now, but the fabrication of custom mounting brackets and such will take a little time.

When I have something to show, I'll start a thread on it and PM you.

Pre-emptive thanking!!!

[BatterPudding]

It should be happy on a mini-ITX PC as there are plenty of people who use lesser power like the Raspberry Pi devices.

Just sling KODI on your home PC and play with it. You can then install that re-touched skin and see how it would work for you as an interface.

Don't be scared by the FAQ. Just start by installing KODI, then add your music folders as a source. Playing with it is the best way to learn.

IMHO start small. Initially ignore the add-ons as they will be distracting. Come back to them when you have got your head around the main KODI and how your music will be handled. You'll be surprised as to how much is handled internally now by the core KODI. For me, the standard scrapers sorted out all the titles, artwork, thumbnails, everything without need of NFO files or external media manages. Just some tweaks needed to how my music was stored.

Noting where some of your music is sourced I am guessing you may well have a bit of work to do with tagging of the files. Get hold of MP3TAG, Musicbrainz or similar and make sure your files are named correctly. At least Album, Track, Artist.


In many ways you are lucky you can't hear any difference above 254 kbps AAC encoded files. If I listen to Dark Side Of The Moon at that level of compression it sounds like it is underwater. When I first digitised my collection of 300 CDs I did it in batches over a year. Converting to 320kbps VBR MP3s. I only had about a dozen discs left to do when I then bought the Onkyo TX-SR806 and Mordant Short speakers. It was mainly for film watching, but I hooked it up to my MP3s and they just sounded dead. Had to get my CDs back out.

So the mission restarted as I converted to FLAC my best quality CDs. Yeah, there are some more poppy albums I don't bother converting, but the majority of my collection is now in FLAC format.

The format for music files has to fit the environment they are played back on. There is certainly no point in going over-kill audiophile in a vehicle. It is about maximising enjoyment, whilst not making it look too stealable, and still having plenty of cash left over for beer.

[CarPC]

It should be happy on a mini-ITX PC...

Just sling KODI on your home PC and play with it...

Don't be scared by the FAQ...

IMHO start small...

For me, the standard scrapers sorted out all the titles...

Get hold of MP3TAG... make sure your files are named correctly...

In many ways you are lucky you can't hear any difference above 254 kbps AAC encoded files. If I listen to Dark Side Of The Moon at that level of compression it sounds like it is underwater...

It is about maximising enjoyment, whilst not making it look too stealable, and still having plenty of cash left over for beer.

Yes indeed, that little 10-watt quad-core Celeron pumps out 6 GFLOPS at 2GHz, more than enough for any DSP algorithm I want to run.

“Start small” is good advice. That’s exactly what I intend to do. Just audio playback until I get that working the way I want.

These “standard scrapers” you speak of, are they part of Kodi? If so, does this mean Kodi goes out to the web every time I play something?

My home PC runs Win XP, and I don’t see myself installing anything more recent any time soon. But Win 7 is recommended for Kodi, so I will wait until the car PC hardware gets here.

In the meantime, I was hoping to learn a little bit about Kodi. It would suck to spend months trying to bend it to fit an application it’s not designed for (if that turns out to be the case).

What puzzles me about the FAQs is that they seem to be written by and for people with a completely different mindset from my own.

Yes, Mp3tag and ffmpeg are invaluable. I use them, together with Excel and Photoshop, for extracting and embedding audio tracks, cover art, encoding parameters, and all sorts of other stuff.

I don’t know what you mean by making sure my files are named “correctly,” though. I have a folder structure that looks something like this:

Audio
  Ambient
    Albums
    Compilations
    Mixes
  Rock and Blues
    Albums
    Compilations

and so on. I have some albums that are stored as folders containing multiple audio files, one per song. For example,

Audio
  Ambient
    Albums
      Delerium
        Delerium - Semantic Spaces - 1994
          Delerium - Semantic Spaces - 01 - Flowers Become Screens.m4a
          Delerium - Semantic Spaces - 02 - Metaphor.m4a
          Delerium - Semantic Spaces - 03 - Resurrection.m4a

and so on. I also have some albums that are stored as single audio files containing all songs on the album. For example,

Audio
  Ambient
    Albums
      Delerium
        Delerium - Epiphany - 2010 - full concert.m4a
        Delerium - Spheres - 1994 - full album.m4a

and so on. With this convention, I always know exactly what every audio file contains, just by looking at its name. Would Kodi consider this naming convention “correct?” Why would Kodi even care how I name my files?

Every one of my audio files has embedded cover art, but all the songs on a given album have the same cover art (of course). So how does “cover art only” browsing work? How do I know which song I’m looking at? And how do I know where I am in the folder structure?

Also, how do I construct an album-level play list? That is, I want to be able to shuffle-play the albums, but for each album, I want to play all the songs in order whether the album is stored as a folder or an audio file. Can Kodi do this?

If 254 kbps audio sounds like it’s underwater, then the file is probably an MP3 (as they say, MP3 is perceptually encoded for fish). AAC is a much better codec. Also, I find that constant bit rate AAC sounds better than variable bit rate AAC at 254 kbps, at least for music. This is highly counter-intuitive, so it may just be a codec implementation issue.

Mordaunt-Short make very fine speakers. They should complement your receiver very nicely. I think you’ve put your money in all the right places.

With that stereo, in a really good listening environment, you may be able to hear a slight difference between 254 kbps AAC and FLAC, which typically runs at about 300 to 900 kbps, depending on the music and the amount of effort that went into encoding it. By comparison, full-rate CD-quality audio runs at 1411 kbps.

Yup... maximum enjoyment for minimum cost and minimum risk of theft is the way to go. My screen will tilt into a horizontal position and slide into the dash when not in use. Everything is flat black; nothing shiny to attract thieves.