Ok, I bought this TP Link 5V at 2.4A battery a couple weeks ago and have since been using it with my Digi+ PRO and Dac+ PRO. I have done the power supply upgrade to both the Dac+ PRO and Digi+ PRO.
Using a USB-to-2.1mm DC plug cable (purchased off eBay) I feed power into the HiFiBerry boards via 2.1mm DC male and female connectors - this feeds power down to the Pi 3 below via the GPIO pins.
Wow is all I can say with using the battery. I get around 15 hours of music playback via this huge battery and it charges overnight, quite quickly using the 2.5A iFi iPower that I was previously using.
From the Digi+ PRO, feeding into my Chord Mojo via Analysis Plus Toslink, then out using an Analysis Plus Silver iPod Cable (3.5mm to RCA), this particular Roon Ready and FPGA Dac combination is well under USD1000 and eerily compares to my PS Audio DirectStream Dac.
I also used the TP Link battery with the Dac+ PRO and Iām expecting to have to buy another one of those batteries.
The soldering for the Digi+ PRO was only made difficult by the soldering iron we had. I donāt think it got hot enough or maybe my soldering technique needs more work (using 4% silver solder). But we got there in the end. Instead of being a 20 second job it took 20 minutes (donāt laugh).
Iāve learnt many times before in this hobby and I still continue to learn and be amazed, that you donāt realise you have noise in your system until you peel back yet another layer of noise that you didnāt even realise was there.