Raspberry Pi & RuneAudio Vs streaming box - with ext DAC

[Pete Shields]

I've managed to get my Raspberry Pi 2 to work with an IQAudio Pi DIGI+ and play back via coaxial and my M-DAC. It sounds great when I play back my Hires music files via an attached hard drive and Runeaudio software and cost me next to nothing to assemble as I already had a spare Pi2 at home.

However, whilst dodging clothes shopping with the wife last weekend, I passed my time by visiting the 3 locally placed hifi stores - and asked the question of whether the Pi is actually any good at transmitting the data to my M-DAC or would a dedicated streamer be a lot better. I'm only really interested in sound quality here as I'm happy with the interface and the rest of the family are all perfectly happy with using the sonos connect I have attached to my hifi, so it doesnt have to be family friendly.

The response was varied. One said you won't really have any noticable sound quality difference. The second said I should buy a pioneer streamer circa £400. Another said sell the lot, my hifi's a bit rubbish, especially the Raspberry Pi and I should ebay the lot and buy a £2,500 Naim system. Not an option as far as I'm concerned.

Due to the nature of the Pi, I'd be unable to take it down to my local Hifi shop and compare. I'd have to borrow/buy from the shop to do the comparision which in the past has ended up with me purchasing regardless!

Has anybody got any experience and done this comparision test? Maybe a What Hifi future article is due here on this?

The M-Dac is a great DAC and does most of the hard work here, so I really want to continue utilising this - but is it worth buying a streamer such as a pioneer, Cyrus or Cambridge?

 

[WinterRacer]

There's really no audible difference whatsoever between different digital transports, but don't take my word for it, have a read of this:

http://archimago.blogspot.co.uk/2016/10/measurements-raspberry-pi-3-hifiberry.html

If you're still worried about jitter and want to put your mind at rest, use the usb input on your MDAC instead.

 

[andyjm]

I've managed to get my Raspberry Pi 2 to work with an IQAudio Pi DIGI+ and play back via coaxial and my M-DAC. It sounds great when I play back my Hires music files via an attached hard drive and Runeaudio software and cost me next to nothing to assemble as I already had a spare Pi2 at home.

However, whilst dodging clothes shopping with the wife last weekend, I passed my time by visiting the 3 locally placed hifi stores - and asked the question of whether the Pi is actually any good at transmitting the data to my M-DAC or would a dedicated streamer be a lot better. I'm only really interested in sound quality here as I'm happy with the interface and the rest of the family are all perfectly happy with using the sonos connect I have attached to my hifi, so it doesnt have to be family friendly.

The response was varied. One said you won't really have any noticable sound quality difference. The second said I should buy a pioneer streamer circa £400. Another said sell the lot, my hifi's a bit rubbish, especially the Raspberry Pi and I should ebay the lot and buy a £2,500 Naim system. Not an option as far as I'm concerned.

Due to the nature of the Pi, I'd be unable to take it down to my local Hifi shop and compare. I'd have to borrow/buy from the shop to do the comparision which in the past has ended up with me purchasing regardless!

Has anybody got any experience and done this comparision test? Maybe a What Hifi future article is due here on this?

The M-Dac is a great DAC and does most of the hard work here, so I really want to continue utilising this - but is it worth buying a streamer such as a pioneer, Cyrus or Cambridge?

Worth considering what a streamer does. At its heart, it is an indexing and address system (it allows you to browse a library and select a track) and it is a format converter (it interfaces with the storage system and reformats the data into S/PDIF format. None of this has any relation to 'HiFi' and is the sort of thing done by all sorts of electronic and computing devices in all sorts of different applications all the time. There is absolutely no reason to buy a dedicated streaming box. Platforms like the Pi with huge user bases often have software which is far superior to the software on the limited production runs of dedicated streamers.

There is however the issue of the clock.

Back in the bad old days, separate DACs relied on the input S/PDIF stream to provide the clock as well as the data. This clock came from the streamer. If you are interested google 'manchester bi-phase mark encoding'. This meant that a streamer with a wonky clock could have audible downstream effects.

These days, any DAC worth its salt has jitter mitigation techniques that should make it immune to any problems with the streamer clock.

Stick with the Pi.

 

[Andrewjvt]

Well done to you for setting up the raspberry pi

2nd dont listen to anyone or let doubt sink in. Put down a small deposit with a dealer and carry out your own level matched in your own home between the 2.

Decide for your self without interference. With the option to return if not an upgrade etc etc

I personally think you will be happy with what you have.

 

[insider9]

I think that as long as the network connection on Pi is stable there shouldn't be a significant difference. I have read about people comparing streamers connected to external DACs and actually hearing a difference. Most recently Linn/Auralic comparison on another thread here. I don't know how that is possible but haven't tried myself so will refrain from criticising the poster.

I'd suggest comparing Sonos Connect you already have to Pi via Mdac and see for yourself. I know Sonos Connect sounds better via external DAC. Would be interested how Pi compares, although I wouldn't expect any significant differences if any differences at all.

 

[andyjm]

I'd suggest comparing Sonos Connect you already have to Pi via Mdac and see for yourself. I know Sonos Connect sounds better via external DAC. Would be interested how Pi compares, although I wouldn't expect any significant differences if any differences at all.

The Sonos Connect is of pensionable age, and is at least a couple of generations behind the current crop of Sonos products.

Back in the days of the Squeezebox/Slimdevices forum when these sorts of things got measured and discussed, the Sonos Connect had the worst jitter performance of any streamer then available on the market.

As I mentioned above, a decent modern DAC really shouldn't care, but if your DAC is sensitive to input jitter, then the Connect isn't much of a benchmark to test other products against.

 

[andyjm]

I think that as long as the network connection on Pi is stable there shouldn't be a significant difference.

The OP is using an attached hard drive. What does the network connection have to do with anything?

 

[insider9]

I think that as long as the network connection on Pi is stable there shouldn't be a significant difference.

 

The OP is using an attached hard drive.  What does the network connection have to do with anything?

My apologies. More coffee required

 

[chebby]

My Quad Vena amp/DAC has USB A and USB B and optical (x2) and coax digital inputs (and Bluetooth aptX wireless).

If I were to use a Raspberry Pi, which one? Which streaming software and what other hardware? (Bearing in mind I already have a DAC.)

Which digital input (of those listed in the first sentence) would be best?

 

[WinterRacer]

USB B-Type if you worry about jitter. Optical if electrical noise is affecting your amp (e.g., you can hear hum).

Otherwise, whichever is more convenient as I doubt you'll be able to hear any difference.

 

[andyjm]

My Quad Vena amp/DAC has USB A and USB B and optical (x2) and coax digital inputs (and Bluetooth aptX wireless).

If I were to use a Raspberry Pi, which one? Which streaming software and what other hardware? (Bearing in mind I already have a DAC.)

Which digital input (of those listed in the first sentence) would be best?

The Vena apparently supports async USB, as does the Pi. If so, that would be the best connection to use.

As for software to run on the Pi, I am afraid I am not current and others may be able to help more than me.

 

[WinterRacer]

Use either a Raspberry Pi Zero W(ireless) or Pi 3, I'd use a Pi 3 with a hifiberry dac+ or digi+ i2s DAC.

I'd probably start by looking at piCorePlayer (emulates a squeezebox and also supports AirPlay) and Volumio.

I've tried a few s/w distros and settled on piCorePlayer as it's the most featured and mature.

 

[Pete Shields]

The problem I had with my M-DAC is that it would only play files up to 96 Khz via USB so I had to opt for an add on board to make it play 192 Khz tracks via coaxial.

If your DAC supports usb connections at 192 khz (you could check via a laptop/computer), all you then need is:

Raspberry pi (I'd go for the latest v3 - although my Pi2 does the job fine)

Pi compatable Power supply, 8gb microsd card, standard USB cable and a cheap case of your choice.

I use free software Runeaudio which is great and there are loads of how to tutorials on this on the web. There are others available such as the almost identical Volumio.

You can pick this up all for between £40 and £50 on the Web.

Because of the M-DAC limitations I bought a IQAudio Digi+ board (£30) and matching case (£15) for another £50 including postage. It sounds great and looks great.

There are loads of tutorials on the various websites.

Go for it, its quite satisfying getting it all working

 

[chebby]

Use either a Raspberry Pi Zero W(ireless) or Pi 3, I'd use a Pi 3 with a hifiberry dac+ or digi+ i2s DAC.

I'd probably start by looking at piCorePlayer (emulates a squeezebox and also supports AirPlay) and Volumio.

I've tried a few s/w distros and settled on piCorePlayer as it's the most featured and mature.

Thanks but why would I need additional DACs?

 

[daveh75]

Use either a Raspberry Pi Zero W(ireless) or Pi 3, I'd use a Pi 3 with a hifiberry dac+ or digi+ i2s DAC.

I'd probably start by looking at piCorePlayer (emulates a squeezebox and also supports AirPlay) and Volumio.

I've tried a few s/w distros and settled on piCorePlayer as it's the most featured and mature.

Thanks but why would I need additional DACs?

You don't if you use USB.

The HiFiBerry Digi+ isn't a DAC btw, it provides S/PDIF output (either optical or coax)

Also, pretty much all the Pi media Player distros support AirPlay, so that's not really an advantage of using piCorePlayer...

 

[WinterRacer]

Use either a Raspberry Pi Zero W(ireless) or Pi 3, I'd use a Pi 3 with a hifiberry dac+ or digi+ i2s DAC.

I'd probably start by looking at piCorePlayer (emulates a squeezebox and also supports AirPlay) and Volumio.

I've tried a few s/w distros and settled on piCorePlayer as it's the most featured and mature.

Thanks but why would I need additional DACs?

Sorry, I failed to remember the scenario correctly. No DAC or DIGI board needed, just use the USB output.

I already run LogitechMediaServer so piCorePlayer made sense for me. As it turns your Raspberry Pi into a Squeezebox, you get the multi-room syncing, iPlayer radio stuff, iOS and Android Apps, etc. You do need to run Logitech Media Server (LMS) somewhere though.

If you use Volumio or Rune, they'll index files on a network share (or attached HDD) without having to run something like LMS.

Here's my Pi3 with the 7" Pi screen running piCorePlayer:

 

[Gray]

I use a Pi3 with RuneAudio, USB DAC and locally connected, self-powered, HDD.

The Pi's Switched Mode power supply would normally also power the connected DAC via its USB connection (as my E-DAC (O-DAC) does not have its own power).

Others have said (and it makes some sense) that the DAC can sound better with an unshared, clean linear PSU. Because it was easy and cheap enough to build a 5 volt supply, that's what I did.

I'm happy with the sound and operation - apart from one small issue where very occasionally the output from Pi to DAC is -20dB down on bootup. A RuneAudio boffin told me how to reset to 0dB and assured me that the level should be retained on bootups. I'd be glad to hear from any other Pi / Rune user that has experienced the same issue.

I think a few of us are on a learning curve with these things but reckon it's worth the (minor) hassle, especially when you compare the cost of 'proper' streamers.

 

[WinterRacer]

Before you consider splashing out on a new PSU this is worth reading : http://archimago.blogspot.co.uk/2017/01/measurements-raspberry-pi-3-as-usb.html
The Pi3 "...sounds great to me and I would not be able to tell a difference between the Pi 3 or ODROID-C2, or Surface Pro 3 sending the audio through ASIO. Maybe the only difference between the machines would be the hum of the Surface computer's internal fan on a quiet night with very low ambient noise in the sound room. Furthermore, there is no objective difference of significance to be found with the RightMark tests using 16/44, 24/96 and 24/192 signals. As for the time domain, there is no evidence of any difference between devices tested using the Dunn J-Test signal that would have any audible impact. May I also remind everyone that this is all with an inexpensive switching power supply... No noise of significance even with the 192kHz test beyond the audible spectrum. I think it would be nice if the believers in linear power supplies can show some evidence that noise can be significantly improved at the DAC output since the cost of linear power supplies can be many times that of a Pi 3!"

 

[andyjm]

Before you consider splashing out on a new PSU this is worth reading : http://archimago.blogspot.co.uk/2017/01/measurements-raspberry-pi-3-as-u...
The Pi3 "...sounds great to me and I would not be able to tell a difference between the Pi 3 or ODROID-C2, or Surface Pro 3 sending the audio through ASIO. Maybe the only difference between the machines would be the hum of the Surface computer's internal fan on a quiet night with very low ambient noise in the sound room. Furthermore, there is no objective difference of significance to be found with the RightMark tests using 16/44, 24/96 and 24/192 signals. As for the time domain, there is no evidence of any difference between devices tested using the Dunn J-Test signal that would have any audible impact. May I also remind everyone that this is all with an inexpensive switching power supply... No noise of significance even with the 192kHz test beyond the audible spectrum. I think it would be nice if the believers in linear power supplies can show some evidence that noise can be significantly improved at the DAC output since the cost of linear power supplies can be many times that of a Pi 3!"

To reinforce Winter's comments, there is a tendency for 'enthusiasts' to want to fiddle with something. If its not the mains cable its the power supply, if its not the power supply is the speaker leads.

The Pi is full of 100s of millions of transistors switching madly away. The DAC is full of thousand of transistors switching away - yet somehow a SMPS plugged into the wall a few feet away is the work of the devil?

Linear PSUs are not noise free - that 50Hz ripple is in the audio band and takes quite an effort to get rid of, and the bridge rectifier diodes switching on and off do produce HF noise. A switcher running at 100KHz is way outside the audio band, and given the high frequency will need a relatively small LC filter to eliminate.

There was a school of thought that the Squeezebox Touch sounded far better with a linear supply than a nasty 'switcher'. It was pointed out by the designer that the Touch had 3 internal switch mode supplies to generate the various supply rails the system needed to operate, and replacing the one plugged into the wall wasn't going to make any difference at all.

To be clear, that's not to say all switchers are good - I am sure there are bad designs out there. What it does mean is that 'linear good, switchers bad' is typical of the usual uninformed old wives' tale that seems to thrive in the HiFi world.

 

[Gray]

I appreciate the comments of the anti-fiddlers (although even they would agree that any Pi owner is, necessarily, a fiddler). You no doubt saw that I didn't say that my Pi sounded better with a linear PSU and having seen the figures in WinterRacer's link it's clear that there could be no audible difference on the analogue of the DAC.

I already had the components and PCB for a linear PSU, all I had to splash out on was a very small toroidal transformer - so my experiment cost about £7 (and I've still got a nice little variable output PSU)

The experiment I'm glad I haven't done so far is to spend hundreds or even thousands of pounds on a streamer to better the Pi!

 

[andyjm]

I appreciate the comments of the anti-fiddlers (although even they would agree that any Pi owner is, necessarily, a fiddler). You no doubt saw that I didn't say that my Pi sounded better with a linear PSU and having seen the figures in WinterRacer's link it's clear that there could be no audible difference on the analogue of the DAC.

I already had the components and PCB for a linear PSU, all I had to splash out on was a very small toroidal transformer - so my experiment cost about £7 (and I've still got a nice little variable output PSU)

The experiment I'm glad I haven't done so far is to spend hundreds or even thousands of pounds on a streamer to better the Pi!

No harm in experimenting, and fiddling around can be a fine thing. When I was growing up, a keen enthusiast with a soldering iron and some basic knowledge could make a significant difference to the quality of his system. There was a large number of magazines catering to this area, and a number published their own DIY designs for amps / speakers and so on - many of which were excellent.

These days, electronics are generally very good, and all the bits that really matter are inaccessible. Circuit board dimensions and SMDs make it difficult to rework boards, and much of the heavy lifting is done by firmware buried inside the chips.

I applaud your efforts with the Pi, my comments about power supplies were in frustration at the endless discussions on this forum about mains cables, speaker wire and ... power supplies. All of which, if properly designed and specified, will make absolutely no audible difference if changed.

I see the same problem in my other hobby, cars. Enthusiasts are reduced to installing 'induction kits' (most of which actually reduce performance) on the basis of spurious claims made by manufacturers. All the bits that really matter are now beyond a home enthusiasts reach.