Raspberry Pi Power supply

[Welder]

Interesting this.

I recently bought the PI 2 B along with the HIFi Berry Dac and the IQ audIO Dac, the reason being one of the people who lives in the house wanted something that sounded better than her computer feeding a couple of rather nasty PC separate speakers.

Anyway, what I put together for her for under 500 euros was the PI, IQ Dac and a pair of Yamaha HS7s plus all cables. I’m fairly well acquainted with what can be achieved with a well thought out file based system and active speakers but I must admit, I was pretty impressed with the end result.

Anyway, having heard the above in my room, I bought a PI 2 and IQ dac for myself. I now had two Dacs (berry and IQ to play with)

My music server has three separate power supplies built in and I thought I would see if I could hear any difference using the 5V 2Amp supply from the server to the PI. I must be losing my marbles, but I thought I could. So, now I’m also interested in two separate supplies, one for the dac and one for the MOB.

I’m rather busy atm building a house so I would be interested in seeing what Richard comes up with for a PSU and what difference if any it makes to the sound and of course, how much it costs.

Oh arr, don’t piss about with USB plugs and sockets, change them all to 5 pin XLR or solder direct.

[Dr Bunsen Honeydew]

Everyone involved in the project please take note - "Oh arr, don’t piss about with USB plugs and sockets, change them all to 5 pin XLR or solder direct."

I REALLY don't want to piss around with USBs.

[terrybooth]

USB is a consideration but only for power. In my application, USB doesn't matter, because my music file store is on my network. But if you want to use an external disk for the file store then the USB connection is the easiest way of achieving that BUT because the PI doesn't have a big enough power supply to power that, another power supply is needed. One of my other Pies has a powered USB Hub into which I plug a memory card and a wifi card. What I thought of doing was to modify a USB cable to add a power supply to it i.e. open up the cable and attach +5v to the +5v connection and ground to the ground connection.

My experiments in separating the Pi from the sound card have born no fruit so far. There is a Dac board available in the States which has a separate power input but the manufacturer advises using this to power the Pie and not to power both the Pie and the Sound board (http://www.gravitech.us/duriosoundpro.html)

Given the number of variants of Dac board and Pi, I'm wondering if this line of enquiry is worth it. If I can get it to work, it will only work with the hardware I've got. If, however, we build a 'powered container) for a PI which provides power and extension of the USB, Ethernet and RCA connections to the case, then you should be able to put any current variant of Pie and DAC in it.

Thoughts, folks?

[Fretless]

Please explain what is so special about the Pi? I have a cheap Asus netbook running via USB into my DAC. Works just fine for network audio and I can use different media players like Foobar and Apollo. No worries about power supplies or compatibility (windows).

[terrybooth]

Please explain what is so special about the Pi? I have a cheap Asus netbook running via USB into my DAC. Works just fine for network audio and I can use different media players like Foobar and Apollo. No worries about power supplies or compatibility (windows).

This isn't just the Pi, it's the Pi plus a DAC board. For me this starts with a 'less is more' approach. The I2S connection between the Raspberry Pi and the DAC board is much more straightforward than on any PC based approach. Sample argument here: https://volumio.org/raspberry-pi-i2s-da ... s-so-good/.

The other thing for me is that fitted in with other things I've got - for instance, I have a wired network in my house as well as wifi and I have network storage devices and I have tablets and such.

So then, the next bit is remote control - remoting to a PC system is cumbersome in my experience. I have a couple of options to do this which allow me to do the basic track selection and play (which is all I really want).

Then there's the price: less than £100 with a little DIY or a bit more to buy one ready assembled.

Then there's the sound. I previously had a dedicated 'audio' PC with an external DAC and this I thought was as good as that.

An that brings me to my current pre-occupation, because I've heard this with a power supply which is beefier than the wall-wart I'm using and it sounded better. (It made more of a difference than previous experiments I've had with different DAC boards and different Pi models).

So, rather like having 1.5/2.5mm mains cable as my baseline for speaker wire, I have the Pi with a DAC board and the baseline for digital music.

[Fretless]

Great, thanks for the explanation and it sounds like this is a definite step up from what I do. Worth looking into.

Maybe the Doc can make you a mini BMU dedicated supply thingy as an experiment.

[alfer]

The BMU thingy is a completely different animal. Was the doc thinking of a linear supply or just a bigger current and smoothing?

I would want to explore the power options rather than base things on one limited listen

[terrybooth]

Nope it isn't a BMU thingy. I've no idea of the detail of what the Doc is thinking of other than it being based on the Phono 2, which is a two box system with the power supply in one box and the step up phono circuit in another box. The idea there, I think, is to modify the top (phono2) box to accommodate the Pi and the DAC and modify the power supply circuitry to match what the Pi needs (+5v). Yes, I'm taking a punt based on a short listen.

To help my thinking I've ordered a torroidal 240v/9v (x2) transformer (based on weight - 2kg)! and and off the shelf voltage regulator module to convert 9v AC to 5v DC (2amp max). Massively over specced for the Pi and if nothing else, I'll have a very effective paperweight at the end of it. If it works, it will have bumped up the cost of my Pi to around £120.

[terrybooth]

A few more bits and bobs have arrived. It seems that my HiFiBerry Dac needs both 5v and 3.3v input to make it work. So I'm coming to the conclusion separating the DAC from the Pie is more a case of 'build your own DAC board' that use one already built.

So the next thing I'm going to attempt is the power supply.

[Fretless]

Looking now at a Pi as a way of getting 24-bit audio playback (which Sonos doesn't do) and I see that there is a Wolfson sound card available as an add-on that outputs SPDIF to an external DAC.

What would work better, this or the matching HifiBerry DAC?