There's a little project I've had in mind for a while to build a self-contained mini-computer music player. This is a leisurely exercise as I also have an elderly Cyrus integrated amp that I want to send to this chap for a wash and brush-up, plus I have a pair of home built transmission line loudspeakers in need of new veneer and maybe a rebuild of the crossovers. So no rush.

I want decent quality output, the ability to run Spotify and to play flac, mp3 etc. from a big drive, a self contained box - i.e. with a built in screen as I don't imagine Mrs WilliamA will appreciate using a phone app to run it let alone Putty or similar, and it needs to look reasonably good.

Originally I was looking at a Pi 3 and DAC Pro with a touchscreen and a separate linear power supply as it seems that powering things via the Pi's USB supply is horribly noisy. I've dithered with this a bit as the costs tend to build up a bit. Linear power supplies of any quality aren't cheap for instance. I've seen one or two self-builds that are absolutely superb like this one that almost do what I want, at a price.

Then some things happened. I found an 8GB DDR4 SODIMM that was left over after I put 16GB in my laptop (moment of insanity). I was given a Cyrus Soundkey at Christmas (high quality USB DAC with headphone amp/line level output). I have a very unreliable ancient Samsung NC10 with a nearly new 120GB SSD in it. This made me think whether I should consider building a mini PC with touchscreen instead if I can find a tiny mobo that accepts a DDR4 SODIMM and doesn't cost a fortune. As a model of what I'm after in the end, the Ockel Sirius A springs to mind, although not so small and hopefully not nearly so expensive.

Has anybody done anything remotely similar, or have any thoughts, ideas for cases, mobos, screens, or anything really?

Is there such a thing as using a smartphone as a remote? That would seem more practical to me than a dedicated touchscreen build.

Why yes, yes there is:

https://raspi.tv/2014/top-ten-android-apps-for-use-with-raspberry-pi

(I have JuiceSSH and androidVNC on my nexus7, both work very well)

Yeah, I have thought about using an old smartphone as a dedicated remote. And in some ways it would be a lot easier. The issue is that the controls are inevitably clunkier and less familiar. I suspect Mrs WilliamA (who doesn't get on with computers at the best of times) would have one attempt to get Spotify running via a smartphone and give up. I suppose an old tablet with VNC might be easier if I set up a really simple desktop on the media centre.

That right there would be a deal-breaker for me, as far as a jerry-build.

What about a phone or tablet using YATSE? My tech phobic wife got on with that really well with a pi running Kodi. Kodi plays nicely with the official pi touchscreen too.

Or alternatively running Volumio or Rune on a pi with would be good if video isn't a concern, but not sure how good the integration with a touchscreen is for them.

When it's up and running, could YATSE control KODI (or whatever) and seamlessly switch to launching and controlling another application, say Spotify?

Hmm, not something I've tried, but I think you'd have to flip between the source (I know you can do it with IP for multiple Pis etc), but I'm not sure you could do it with a cloud based service.

I'm surprised that a Pi project is more expensive than any PC build, DIMMs notwithstanding. Is it the touchscreen and box that are piling on the theoretical cost? If so, have you looked at third party knockoffs? I've always bought my arse-end stuff from Gearbest and they've never seen me wrong.

The single most expensive item is the power supply. My reading suggests that the main problem with the Pi/DAC combo is the Pi's power supply. The solution is to use a better linear power supply to power the DAC separately and these aren't cheap, not because there aren't plenty around the £20 mark, but because most are so noisy that they're little better than the USB power on the Pi. 

The point is that once I start adding in the different parts (and I've looked at dozens of different supplies, DACs, screens, cases, etc etc) and add to that the unknowns such as having to mod the DAC to power it separately which involves buying additional components, I wonder whether I really want to head north of £250-£300 when it may not even improve on the headphone out from a laptop.

A couple of years ago when I had that unusual event, a party, I set up some sound which was a half-OK amp and speakers with the headphone jack from a laptop as the source. I made a Spotify playlist called 'Now I am 60' on the 'Fuck you, I like it' principle. I was very disappointed by the sound quality. This Christmas, I played it again with the same system and my current laptop. It was OK but not brilliant. Then somebody gave me a Cyrus Soundkey, a USB DAC. I connected this to the laptop and then to the amp. The difference was enormous. It went from OK to sounding like a proper source component, up there with a separate CD player.

This might all be a bit wishy washy for some tastes: a bit too close to the multi-thousand-pound speaker cables and carbon-fibre mains plugs. Well, fine. I'm not after that. I just want a box that has the flexibility to play spotify, some kind of music player, and maybe even get at my wife's iTunes library. Somewhere I can dump flacs of CDs. And I want it to sound a bit better than OK. 

Edit: Yes, I have tried Kodi and a Pi as a source (well, it was XBMC when I tried it) and yes, it's a good media player and the overall sound wasn't bad. 

 

Pickup a relatively cheap touchscreen laptop and use the USB DAC?
Or would that not be user friendly enough?
One of the foldable ones where the screen can turn all the way back, then maybe find a way to mount it.

My Dell laptop, Inspiron 13 5000 range, does that. And is it the Lenovo Yogas that do too?

Been there with the Pi DACs and experienced the issues with noisy PSUs. Previously attempted to build a Pi based audio system for the bathroom. Was too unreliable and ended up with a Chromecast audio, which was more suitable for occasional usage.

Still keep meaning to put together a small system for my dining room (read: dumping ground) so I can listen to music in a nice environment.

I'll point you at the stuff I got for my kitchen setup, it's not a million miles away from what you're trying to do. If the kit list isn't in the thread I started last autumn-ish, I'll find it tonight. Out and about at the minute, so will link it when I can.

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.