The laptop thing isn't a million miles from what I was pondering. 



 

That would be interesting - thanks

In addition to the Pi3 and the 7" touchscreen I got these:

DAC: http://iqaudio.co.uk/hats/8-pi-dac.html
Amp: http://iqaudio.co.uk/hats/25-pi-amp.html
Amp power supply: http://iqaudio.co.uk/home/24-19v-power-brick-65w.html

They appear to have updated the hardware since I bought mine, so check for any incompatibilites if you go down this route.

I also got a pair of generic 8" speakers (Pyle brand) that could be mounted in the ceiling.

The amp board only has a small screw type connector for the speaker wires, so you're not going to get anything in there that has a large wire gauge. However, the cable I got was 15AWG and fits fine.

The sound quality is good (I mean we're not approaching £1000+ hifi seperates here, but it's way better than I expected) with no hiss or other cable noise distorting the music. That's all subjective of course and you'll no doubt find differences playing it through your speakers.  I'm running Kodi and streaming the media from my NAS. I've got a few external BBC radio stations saved in there too.

 

Looks like they've gone for a laptop type power supply and when looking at cheap Class D amplifier boards ages ago many people recommended a good laptop PSU if a linear supply was out of the budget, which for many people was since the actual amplifier boards (which were very good quality) came in at around £10. Currently using an old laptop PSU myself for the bathroom setup.

I used a cheapo laptop PSU originally and the actual power supply started hissing, clearly couldn't cope with whatever the amplifier board wanted!

How do you power the Pi and the DAC+? The solutions I've seen to avoiding powering the DAC via the Pi's USB socket involve modding the DAC to add a power-in socket and possibly desoldering the track for the power connection to the Pi's header.

Edit: crossed with Ant

I think my solution to reduce or remove hiss/noise was to use a decent 5v USB power supply, but can't exactly remember if it worked 100%. I also remember having ground loop issues, so it may have been a ground loop isolator that fixed my problems.

I wasn't using the type of high quality HATs that graphitone is using so it may all be related.

That ground loop isolator is now in use in my car because of a similar issue with a noisy 5v USB supply and a Bluetooth adapter.

The Pi, DAC and amp are all powered from the laptop type PSU I linked to. It plugs into the amp itself and powers all three through the onboard connections.

In my setup, you can power the screen from the Pi too with the ribbon cabled included with the official touchscreen, but I kept getting the not-enough-power symbol appearing, so powered the screen seperately.

Hmm. That really is interesting. I saw a version of the DAC pro pre-fitted with a socket for a power brick to connect to, but I forgot where it was and Google hasn't been my friend. I wonder why they don't make one when it's such a popular mod that HiFiBerry publish instructions online.

OK, an update in case anybody cares (or not, since I'm posting this anyway). Decided, if that's the word, to combine building a mini music-player computer with a bit of extra online storage. So I'm going to build a tiddly little PC with a couple of large capacity HDDs inside. Having looked at loads of ready-made ones and decided they don't quite do what they want for one reason or another have ordered one of these from ebay.

Interesting though to consider a project where there's a range of enthusiasts doing different things with tiny PCs but the various manufacturers don't have much interest in it. It was amazingly hard to source a mini-stx mobo*, and they cost stupid money new. And they often come without power bricks which is fine except that it's not always clear where to get a suitable one and guess what - they cost stupid money too. Those do seem to be the rules-of-thumb: lack of info, scarcity of supply and stupid money. 

*and I wanted one that had support for SATA HDD/SSD as well as as M.2. When I say stupid money, that includes postage and tax since they're almost unheard of in the UK. 

What OS and media player are you going for?  And what format are you storing the music in?

I haven't yet decided on a media player. In some ways that's not so important because (as per my original post) it's quite important that Mrs WilliamA can get her Apple library and that we can both get at Spotify where we have playlists. As for other stored music, I'll probably settle on flac as I want to dump some of our hundreds of CDs, so several media players will do. OS will probably be Windows 10 as Mrs W knows her way around that.

On the storage side, we're mainly looking at music although some of my thinking is that extra disk space could help with the shortage on my main backup PC. 
 

Yeah, smaller = order-of-magnitude more expensive. Must be a novelty/enthusiast/lack of demand thing.

That's a thing I've found with using a full pc OS for a dedicated function: a slow mission-creep, because it can.

I can understand it, because the main market as far as the manufacturers are concerned is industrial and the whole thing is a bit of a moving target. Do the buyers want a traditional mobo in miniature or something far more granular: some kind of SoC arrangement without all the extras? The STX format is already a bit niche which is why the CPU and RAM support is out of date or patchy. The board I'm getting is socket 1151 but only CPUs up to 7th gen, and DDR4 although others boards are mainly DDR3. When I started looking I had no idea how many different attempts had been made to create a standard for embedded applications such as the Intel NUC things. I suppose the most popular very small form with home builders is mini-ITX and even that is on the wane. 

I was after low(ish) processing power somewhere in the range of Celeron up to i3, but not as feeble as the Atom range which starts to struggle if anything serious is waved at it. I also wanted support for standard SATA drives. I thought it would be nice to use up some DDR4 SO-DIMM memory I have. It had to be small and preferably not use a big standard PSU and quiet so it can sit next to us without being annoying. Not much to ask.

Anybody got a spare i3? Pentium, Celeron??

I use an old HP SFF office pc with athlon something, Ubuntu 18.04 for a home music & file server (MrsD.s old pc, she ran xp on it)... probably massively bigger than what you're going for, but free. It sits under my scanner so doesn't really eat up any extra space.

 :-D Yes, I'm aiming at about 6x7x4.5 inches. So a bit smaller. That said, my back-up PC is about the size of an enormous old desktop and has noisy Corsair water cooling, but it sits in the spare room so that's OK

There's a punk to New Romantic progression. A visionary manufacturer strips out all the fat and offers a refreshing barebones machine that challenges users. Then to build business they start to offer add-ons and new iterations with greater capabilities. Before long, it's just another machine with all sorts of gingerbread and bloat lashed on.  Then somebody has the bright idea of stripping out all the fat.

I prefer Bauhaus to Roccoco progression (I actually like both styles but, as I said, I've a low threshold of boredom).

It's the circle of life.

You say dumb terminal, I say thin client...