HOWTO: Building and Installing the Raspberry Pi 3 "Touch" Audio Streamer.

Raspberry Pi 3 + 7" Touchscreen (left) and Squeezebox Touch (right): for the Pi device, I still had the plastic screen protector on in the picture, hence the bottom left tab...

I showed you guys this picture last time of the Raspberry Pi 3-based Streamer device with official 7" touchscreen and HiFiBerry DAC+ Pro. As you can see from the image, it's very much capable of being a "clone" of the Squeezebox Touch. Furthermore, it's highly affordable with even more hi-res audio potential such as the capability to stream bitrates beyond 96kHz (remember, the stock Touch goes up to 96kHz, enhanced to 192kHz with Triode's EDO plugin).

In this post, let's have a closer look at the device and some instructions / suggestions to build one.

I. HARDWARE

First, let's address the components I'm using to build this device:

1. Raspberry Pi 3 Model B (~US$40).

Note that I added a little "stick on" heat sink over the CPU -  generally not necessary but might drop the temperature a few degrees.

2. Official Pi 7" touchscreen (~US$70). I'm sure other screens would work well also; it's mainly a matter of finding a good enclosure when you put it together and making it cosmetically appealing.

3. SmartiPi Touch enclosure (~US$30). I have the one without LEGO front studs so as to look cleaner but feel free to get the LEGO one if you want to adorn the device with your favourite Lego superheroes. I'm sure it'll sound the same :-). This enclosure started life as a Kickstarter project. It includes a convenient Y-cable for efficient USB power connection and its own longer ribbon cable (15-way FPC) for the screen. By using only the DSI (Digital Serial Interface) connector, the GPIO port is open for HAT boards like a DAC or S/PDIF digital audio board. There are other cases out there of course like this one, but I think the SmartiPi Touch with its adjustable view angle and well-thought-out design (cut-out for CPU heatsink, ability to use HAT board) is the best design I have seen to date.

It's made of reasonably strong ABS plastic which is fine. However, I certainly would love to see higher workmanship in the quality. For example, the edges could be smoother and the flat parts could have less inconsistency. It would be awesome to see a brushed metal enclosure for example. Maybe some enterprising company can bring something like that out without costing more than the actual active electronics!

4. OPTIONAL: HiFiBerry DAC+ Pro (~US$50) for high quality analogue output (previously measured). Remember that USB digital output is already available from the Pi without any HAT board. Of course, if you prefer digital S/PDIF connections, get the HiFiBerry Digi+ Pro (~US$55) (the best of 3 models they have, with dual crystals for more accurate 44/48kHz samplerate families).

HiFiBerry DAC+ Pro HAT sitting over the Pi 3.

5. A decent USB 5V 2.5A power supply - remember, you need a bit more current to power both the Pi and touchscreen. You probably have one at home already but usually these are <2.5A, an inexpensive one will do (~US$10). Notice in some of the pictures below there's a little yellow "thunder" icon shown on the top right of the screen as a warning for low power. Usually it's a warning that doesn't affect the operation/sound with a typical 2A supply. With a 2.5A power supply such as the one linked to here, there is no warning.

6. Grab a reasonably fast microSD card for the OS and software install - like this SanDisk Ultra 16GB (~US$10) will do.

So the price for my build including the DAC+ Pro would be a grand total of: $210 + tax (current Amazon prices rounded up), assuming I needed to buy the power supply and microSD card (both of which I already had lying around in the home). Not bad at all. Just have a look at how much a new-in-box or lightly used Squeezebox Touch goes for these days.

Everything laid out and ready to assemble...

Putting the hardware together isn't a big deal and should easily take you less than an hour if in a rush. It was a fun project I did with my son over an afternoon last month.

No need for me to repeat what others have done! Here's a very thorough video of how to install the SmartiPi Touch case, touchscreen, Pi 3, and HAT board:



Simpler than any computer build I've put together :-).

There were a couple of things I needed to do in my build to keep in mind. First, my heat sink fins were a little larger than the cut-out for the SmartiPi Touch case. I had to use some needle nose pliers to bend the outside pins about a millimeter in to fit it within the SmartiPi plastic heat sink cut-out:

Note the cut-out with heatsink visible inside.

Second, one of the solder points from each of the analogue RCA connectors of the HiFiBerry DAC+ Pro was a little long to sit over the case flat. Again, I took a few seconds with the pliers to bend them, this time out by 90°:

Here are a few pictures of what the device looks like after assembly, powered by a battery and connected to my Server with the built-in WiFi:

Notice that I can power the device quite comfortably with an APC Mobile Power Pack Li-polymer battery meant for cell phones and tablets (10,000mAh with 5V, 2.4A USB port). 

Rear: You can see the HiFiBerry DAC+ Pro hitched to the back. Note that the RCA connectors point down; be careful with unusually large/long/stiff RCA cables. There's the Y-connector for power to the screen and the Pi. Also, notice the LEGO connector up top for Pi camera and whatever adornments :-).

Left side: The Pi has ethernet and USB ports off the side. Cosmetically, you can get something like a 90° USB port adaptor so the cables don't obviously stick out the side too much.

II. SOFTWARE

Okay, here's then how to get the software loaded and getting piCorePlayer "live" on the device.

1. Grab piCorePlayer off the website - notice that the current version as of this writing is 3.11. I grabbed the "Audio optimized" version:

2. Transfer the software over to your microSD; you might need a card reader/SD adaptor (L: drive in the image below). I use Win32 Disk Imager. Mac folks can use ApplePi Baker.

3. Stick the microSD in the Pi 3, connect to wired ethernet (remember, WiFi not set-up yet), plug into power supply, and give it 5-10 minutes to start up. Then go into your router to find the IP address of your device. Other ways include running Net Analyzer if you have an iPhone/Pad connected to your router. Also, Advanced IP Scanner on Windows could be useful.

IP addresses on my LAN:

As you can see, my piCorePlayer IP is 192.168.1.121.

4. Now that we have the IP address, log into piCorePlayer with that address and set-up a few things. For example, here I'm setting the output to be through USB but as you can see, I have the option for using the I2S HiFiBerry DAC+ Pro HAT instead among other popular DAC/digital out boards.

For completeness, if you ever need to SSH/PuTTY into piCorePlayer, remember that the user is "tc" and password is "piCore".

5. Now, it's time to get the touch screen GUI working. That involves activating jivelite. First, go to the bottom of the control panel and click on "Advanced":

Click on "Advanced". Notice "Audio output" and "Output setting" are set up for my USB TEAC UD-501 DAC.

Now click on "Tweaks" up top, then enable jivelite and click "Save".

With that you should see piCorePlayer downloading, installing and starting jivelite. And the touchscreen should come to life:

In the event that the screen is upside-down like what you see above, just change the "Rotate screen" setting below "Jivelite" activate, and save. The unit will restart with proper orientation.

6. Feel free to play with piCorePlayer! It's very powerful and can even run LMS if you have music mounted and want the Raspberry Pi to run as a music Server itself to stream to other devices in the home.

7. Modify the settings in jivelite to your preference:

I like the screen to turn off when not playing anything to save power...

Also, I find the default max brightness too bright. A value of 25-50 is good enough for me in my relatively dark sound room on relaxing evenings:

It's all relatively straight forward. For those more visually oriented, here's an excellent video HOWTO:


Notice on the video, he's using the Meridian Explorer 2 DAC and speaks about specific settings for that USB DAC and making it work with MQA... Also, he does a great job with getting LMS running from within piCorePlayer so your Raspberry can act as a low power Server to other devices on the network.

III. TWEAKS

Remember, with an open architecture like the Pi 3, there are all kinds of other things you can do. For example, other then piCorePlayer, you might want to try Volumio with the touch screen (check out the "Touchscreen plugin" section on this page). RuneAudio is also possible, check out this video.

Also, remember that the Pi 3 has quite a capable quad-core CPU. That's enough processing power for some simple DSP... Upsampling to 384kHz to feed my TEAC was no problem through piCorePlayer and I'll perhaps spend some more time on this in a future post showing setting options and impulse responses to play with. There's likely not enough computing speed for full-on high-resolution stereo room correction but perhaps decoding for HDCD or MQA Core (24/96) could be done? I'm throwing the MQA decoding idea out here because we know the Bluesound Node 2 has a software MQA decoder already and the CPU on that device is just a 1GHz, likely dual-core Cortex-9. Of course this is not about hardware ability, but licensing issues and legalities around decoding the MQA file.

Remember, for the tweakers, give my Convoluted Rationalization And Audiophile Perceptions (CRAAP) settings a try. Just take the microSD out from the Pi 3 after the piCorePlayer setup. Stick it in a card reader on your computer, and apply the following to the "config.txt" file on the microSD <Thanks Seng Yew Meng for correcting over_voltage_sdram!>:

arm_freq=800
sdram_freq=400
core_freq=400
gpu_freq=300
over_voltage=-4
over_voltage_sdram=-4
gpu_mem=16

Unmount and stick the microSD card back in the Pi 3 and reboot... Voilà - underclocked, undervolted Raspberry Pi 3 with potential to save you a few pennies in electrical costs, keeps the device cooler, and sounds great :-). Still plenty of speed and snappy user experience. Can't go wrong with that IMO... [November 2017 Update: These days I run the undervolting with -2 instead of -4... Just found it more stable during the heat of summer.]

IV. CONCLUSION

Have fun! As I discussed previously, it really is great how much we can accomplish with inexpensive computing gear these days. This device has been trouble free for the last month and "sounds" great. I'll do a few measurements in the days ahead and compare it to the Squeezebox Touch. Particularly, I am curious if the touchscreen adds any noise to the analogue audio output from the HiFiBerry DAC daughterboard.

One last thing... Remember that Squeezebox devices are supported under Roon. Although I no longer have a Roon setup currently, I "hear" that piCorePlayer works well. However, running Roon Bridge on the Pi does provide important RAAT features like gapless playback, better integration into the software zones, etc... Unfortunately, I don't believe there is currently Roon Bridge support of the touchscreen - hopefully this will change in the near future! Even a simple UI and ability to display artwork on the screen with Roon would be great.

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Costa Rica is a great country to visit and travel through over the last 2 weeks... But as an audiophile, one of the first things I did when I got home was to fire up the sound system and enjoy a couple of hours of sweet music. Cannonball Adderley's Somethin' Else fits the bill nicely as my welcome home album, followed by Bowie's Sound + Vision box set (the 4 CD 2014 remaster at DR10 sounds OK, have not heard the 1989 Rykodisc original).

Like last year in Mexico, the Central American electronics stores seem to like carrying big and "aggressive" bad-ass plastic speakers with pulsatile multi-colored LEDs adorning the devices:

Glowing speakers, baby! :-)

You guessed it, very uncontrolled, bass heavy, bloated sound... "Cool", I guess? But certainly not "high fidelity".

As usual, I hope everyone has a great week ahead.

Hope you're enjoying the music!

Addendum: May 20, 2017
MEASUREMENTS for this "Pi Touch" device is now up.