Project music streamer

Hi all! Welcome to the buildlog of my project; a cd-ripper and music server/streamer!

My Background
Was always big into thinkering ever since I was young and I have a strong sense of how things work. Now I'm a full fledged Civil Engineer with great experience in autocad (2D), some Inventor (3D) and also system engineering. However I never stopped thinkering especially building my own pc's. Furthermore in a previous job I did some maintenance to electrical schematics in autocad (DXF exports) so I do have some basic knowledge which made me believe I could take on this project I'm about to show you.

How the project came to be

For like the past 20 years I've had a HTPC; low power totally passive (Love it!) which was way better than any settopbox my provider could offer. It does live TV, DVD/Blu-ray playback and any video I throw at it. But music it doesn't do that well. Also for the most part it's made with off the shelf items and the challange was mainly with selecting the components. For a long time I wanted a music streamer and a fewyears ago I started looking into it. But; I wanted it to look like any high quality audio equipment in a sleek tv cabinet. There is the first challenge; space constraints. The second; I could buy some streamer and while they're out there and really expensive it justdoesn't give the satisfaction of something you made yourself. I know lot of people can relate to this. It's also about learning stuff along the way.

First sketches and ideas

Once I figured out what I wanted I started collecting parts and made a first impression for a DIY forum elsewhere;

These were modelled in Inventor (I don't hold a license anymore so will need to look into some replacement if I still need 3D) based on the pessante/dispessante series of this webshop; Home | HiFi2000 . They're hugely popular with the DIY amplifier scene. Go check them out. Even while they're were pretty helpfull they only offer 1U and 3U cases; this doesn't fit with my requirements being low profile case. I did look into the 1U versions but I couln't match the power requirements with the size of the case and the size of the computer board. Why not go with a raspberry pi you ask? the software I like is made for x86.

I figured I could make custom panels; already have some experince having a custom made frontpanel made of steel. What I really needed was a good resource for side panels. Well then there's this webshop offering a nice selection of audio DIY stuff and also project cases! DIY enclosures and cases | HiFi Sono DIY | Audiophonics - Audiophonics I did look at some other suppliers like Conrad but just never could find what I was looking for or their side was a mess for finding stuff. Even while the shop doesn't sell the side profiles themself that's ok for me.

So now the case itself looked more than doable and I almost went forward. The snag; the power supply. I want a toroidal power supply with a AC-DC converter board. Making it true audio grade pc. Hey else it wouldn't be much of a challenge. But now the case ratio came back to hurt me; up to 50 watts it's 50mm, above 60mm. You guessed it I just couldn't make it work. First wheteher you pick an Intel Atom / T series cpu or even an AMD GE series you always go above the 50 watts. Not in nominal use mind you but while booting/shutting down, maybe even CD ripping, you really need that power. I meassured peaks up to 70 watts in a test setup. Just couldn't do it.

The challenge became the power requirements VS the size of the side panels.

Sizing the project up

My first idea was going with amplifier heatsinks before I went; due to the power requirements I don't need to go this way;

Look at the logo I made just to break the clean look a bit!

While trying to size stuff up in Autocad (don't need that many ports perse for example) I quickly found out I'd always need a slot-in CD drive for ripping, and a floating one at that not the kind you screw to some posts.

Also; the power supply provider I used here went out of business; that became somewhat problematic for me but found another option (with a larger footpint unfortunatly. About the audio module at the bottom I'll tell you more later on.

But that board? Why not mounting it to the backside as a regular pc? Well.. I want to use Neutrink sockets and second the mounting wouldn't be that great. Also if I remember correctly the heatsinks provided 50 or 52mm internal space which was just not good enough. But after the power supply (LT3042 if I remember correctly) went out of business I had to re-arrange the stuff inside and I just couldn't make it work. Just couldn't. if you look closely at the audio module and ITX it interferes as it needs to occupy the same space. The case needs to be deeper and as a result the heatsinks not only become higher but also wider; leaving less horizontal space. I just never could make it work with ITX so I needed to look at another solution.

Final requirements

Finally I came at the following set of requirements

- Case has to be 19" wide and have a classic look

- Not too high

- The motherboard has to follow a standard format; upgradability/repairability is a must for me (will make a new post about that one so stay tuned!)

- Socketed back so it's trully upgradable

- The audio out section gets a "module"  treatment so it's also upgradable

- The PC needs to be low voltage and passive; I don't like noise and if it requires a lot of power it won't fit.

Parts
There are some parts I already have! Also some I rejected for project use.

The audio module!

These PCB's can be easily sourced from ebay/ali express etc. The green one is an Amanero clone offering upgradable clocks! Like I mentioned before I just like upgradability/thinkering. This is something for another time though. Also got me XMOS module with different kind of upgradable clocks.

The black module is the actual audio out; FLTR: AES/EBU 32/192, Coax 32/192, Optical 24/96, I2S 32/384 (but mostly module dependant). Also does DSD audio out.

It also has I2S audio in instead of the module and the lattepanda supports I2S out! No idea if I want to use that or not but many people going the raspi route like that a lot.

Another one but green PCB; I liked this one less. Also I like to avoid using green PCB's and having it all nice black. Even if nobody but me ever gets to see it.

A nice button I sourced; didn't like going with the vandal button as I wanted a classic look. While probably easy to make these were hard to source. Would have possibly liked them a tad bigger. 

From the Streacom spare parts webshop I found this nice PCB! And black! I'm already able to make this myself in KiCad but as I needed something else anyways I just picked it up!

There's a story behind this one... this was the part that holded me back for years; slot-in is hardly used, mostly in expensive cases and couldn't find them either loose or in a cheap donor case. Then I found a webshop in the UK but Brexit... also they just didn't respond (bad customer service!). Ordered two through a package forward service but only got one... again no response. Also while advertised as new it was delivered all scratched up really badly.. just couldn't reject it as hard as this was to get. But...

Then there was the Streacom spare part webshop! To the rescue. The reason I went to look there in the first place is I got a HTPC with a Streacom FC5 v1.0 and like it a lot! In fact I like it so much I initially looked for years for a 2nd one and just couldn't find it for a right price. Once I found one I came to the conclusion it wasn't for this project.

Actually I had more parts from years of collecting but decided as I won't go the heatpipe route I wouldn't make the start post any longer.

Lattepanda MU
So here the MU comes in; I have both a power and dimensions problem.

Here's some standard dimensions for x86 relevant for SFF;

Honorably mensions;

Raspberry pi 85x56mm

Carrier board lite 146x102mm

Already decided to go with the STX format; initially planned to go with the Asrock deskmini boards but the CPUI I wanted for it is not available.

After looking into this project I came up with this format;

You'll be pleased I decided to put my project forward for the event; Try LattePanda Mu for FREE: Build and Shine with Your Own Design!- Lattepanda Forum

And I'm pleased to tell you 'm selected! I was already planning to opensource my design but I would have done that anyways; love the idea of sharing and someone can improve upon your works.

I might need some help upon the way as I'm a civil engineer and not a electrical engineer but I've done some simple pcb's in Kicad 6/7 already!

So about the PicoPSU header; some speciality m.2 cards still require a floppy header; the Sata to slimdrive adapter for my build as well. Many of us probably have old or defective PicoPSU's laying around with really nice cable looms. It's just a no brainer as it needs both 5v and 12v already present.

About the CEC module; the Pi does this natively but I love and actually use on my HTPC.

Here's two that came to mind; Skull Canyon NUC - CEC Adapter - Pulse-Eight - Ultra HD Distribution and Control Products

Intel NUC HDMI-CEC Adapter - Pulse-Eight - Ultra HD Distribution and Control Products

I actually have one of the NUC with custom cable loom on my htpc board!

Yes I could just use the external box but I dislike a cable mess behind my equipment.

Besides I still want to test powering my HTPC on externally.

Many years ago Intel introduced the HTPC header basically just for this + IR and it never went of; so if possible I really want to add this to the list!

Do you like this? have recommendations? Please post!