HiFi Subjectivist ¦ Audio Forum ¦ NVA User Group

Having satisfied myself that changing the power supply makes a difference to the sound quality you get from the Pie, I'm now looking at the idea of separating the DAC from the Pie and powering that. I started by looking at the boards available for the Pie, but that seems not the way to go. Before these existed, people were connecting DACS to the Pie. So I've been looking at DAC boards.

And here's what I'm eyeing up now. http://www.ebay.co.uk/itm/AK4399-32bit- ... rmvSB=true. This seems to have some following in teh audio DIY community https://myl8test.wordpress.com/audio/ak4399-dac/. Now my soldering skills are not good, so what I'm thinking off is getting one ready made http://www.ebay.co.uk/itm/AK4399-DAC-as ... 418181a696 and figuring out how to plug it into my Pie (ie. probably solder a connector block onto the DAC board and make a ribbon lead to connect to the Pie) and then feed it from the second feed of my transformer through another PSU board.

Any thoughts? Anyone out there doing this?

Is it too easy to just buy an IQaudio PI-DAC+ (i2s fitting), fit it and enjoy the music.

What you are now heading for Terry is a Digi board on the Pi and a toslink/coax connection to an external, self-powered DAC.

Although from what I have read the I2S connection is superior in terms of possible jitter. But you'll have to turn that into an audio signal (digital and then analogue) somewhere down the line.

I am still amazed by the quality of the Pi B+/ HFB Digi+ combo and tweaking the output parameters has a definite effect.

alfer wrote:Is it too easy to just buy an IQaudio PI-DAC+ (i2s fitting), fit it and enjoy the music.

Yep, been there, due that. And yes, it sounds good. I'm just following a hunch that it might sound betterif I can power the dac separately.

Fretless wrote:What you are now heading for Terry is a Digi board on the Pi and a toslink/coax connection to an external, self-powered DAC.

Although from what I have read the I2S connection is superior in terms of possible jitter. But you'll have to turn that into an audio signal (digital and then analogue) somewhere down the line.

I am still amazed by the quality of the Pi B+/ HFB Digi+ combo and tweaking the output parameters has a definite effect.

Yes, maybe I should just surrender and buy a Digi board I've used an outboard dac (Asus) connected to Pi's Usb and I wasn't impressed.
I am, I admit, 'philosophically' drawn to the apparent simplicity of th I2Sinterface.

terrybooth wrote:

alfer wrote:Is it too easy to just buy an IQaudio PI-DAC+ (i2s fitting), fit it and enjoy the music.

Yep, been there, due that. And yes, it sounds good. I'm just following a hunch that it might sound betterif I can power the dac separately.

Why. If the power supply to your Ri is adequate then the i2s supply is of the same quality as the Pi. Surely one cannot improve on that and why would you need to?

Separate DACs in boxes using USB/SPDIF or what ever may benefit. This is not the same.

alfer wrote:

terrybooth wrote:

alfer wrote:Is it too easy to just buy an IQaudio PI-DAC+ (i2s fitting), fit it and enjoy the music.

Yep, been there, due that. And yes, it sounds good. I'm just following a hunch that it might sound betterif I can power the dac separately.

Why. If the power supply to your Ri is adequate then the i2s supply is of the same quality as the Pi. Surely one cannot improve on that and why would you need to?

Separate DACs in boxes using USB/SPDIF or what ever may benefit. This is not the same.

The Pi uses 5v DC input but then transforms that to 3.5 volt somewhere on the board. So the theory is that an external PSU can do this 'better' than having that done onboard. I do accept that this may not be the case and I could be overcomplicating things, but I won't know that until I try.

In the case of the DAC boards I've been looking at, they need +12v or +15v DC power input which won't be supplied by the Pi.

How about a USB dac powered 5V by PSU and connected to Pi via I2S ?

Fretless wrote:How about a USB dac powered 5V by PSU and connected to Pi via I2S ?

I've tried a USB DAC with Volumio and the Pi. I'm not sure what happens over USB on the Pi. But I wasnt' impressed with the results. Now whether the HiFiBerry Digi and Toslink sounds better, I don't know. I presume it must do or why bother manufacturing them in the first place? So far as I am aware - and I haven't researched this - HiFiBerry are the only manufacturer making a board with Toslink connections on it. There is a lot on the web about the shortcomings of the USB implementation on the Pi. And this is very much a DIY market, and they sell direct, so I don't see HiFiBerry making it just to cash in on a market.