Phat dac


#1

I picked up a phat dac, I managed to solder it and set it up, the sound is blasting out the speakers, cool!

The only issue is the picade volume controls no longer work. Can anyone advise?


#2

actually, it’s a power issue! It works fine but if you crank it up the screen shuts off, guessing the picade board shuts off stopping the buttons. Sorry for the double / pointless post :)


#3

So that Phatdac would still be using the 3W amp from the picade board?


#4

Yes, the pHAT DAC does not have its own amp- it produces line-level output- so you would still use the Picade Amp to drive the speakers. Basically a quick swap in for decent sound!

@Bootnut what power supply are you using? Between pHAT DAC, Picade and possibly the screen you’re going to be pushing things to the limit and starting to brown things out. That Picade Amp is a hungry hungry hippo when it comes to power consumption!


#5

Thanks for the info. I’m using an IQaudio digiamp+, only issue is volume control via the picade PCB doesnt work now so had to install a rotary encoder to control volume :)


#6

Ah, yeah, the Picade PCB will have trouble controlling volume if you’re not routing through its Amp!

You might be able to rebind the volume keys to actually change the volume at the OS level, rather than on the Amp itself. Alternatively if you’re not using them for volume ( a rotary encoded is a much more elegant solution ) then you could remap them to game controls. A couple of extra buttons would certainly come in handy.


#7

Thanks Gadgetoid. I will look into that. It’s not a big deal controlling the dac volume via the rotary encoder but given the choice i would prefer to use the original buttons on the left of the picade to control it. Just need some kind of dremel to drill a hole in the back of the picade door as currently the rotary encoder is just hanging loose from the GPIO


#8

Hi, I’m using the official raspberry pi power supply. I picked it up along time ago, pretty sure I got it here, did they ever change spec? I ask as I’ve always had issues with high volume and the 8inch screen / picade cutting out, I am looking at powering the pi and screen separately but I’d like to retain 1 plug.

The phat DAC works really well, no more hissing! I was pretty scared of the soldering, I had visions of a hot mess all over that DAC board but it was actually pretty easy (might have another go one day)


#9

Nice one. The beauty of the digiamp+ is that it powers both the pi and digiamp via a 15V 3.33A (50W) powerbrick so there are no power issues at all.

It also pumps out 2x20W to the speakers, so it’s super loud :)

The digiamp+ however, is significantly more expensive than the PhatDac.


#10

IQAudio sure know their stuff. Really nice folks, too!

Some guys on these forums have come up with solutions for powering display/Pi from the same, more powerful, power supply, and I definitely understand your desire to retain a plug!

A small, powered USB hub with a 3Aish power supply should do the trick. We should probably test some options for this and come up with a known good solution, but right now there’s just no time. Negative time, in fact!


#11

I will add that i swapped out the standard picade 3W speakers for 2x Tangband 30W speakers. also tried Visaton FRS8 but they are not up to the quality of the tangband.


#12

A hub was my thinking, I need to see what I can find, one with a switch would be awesome, I could leave it plugged in that way.

I’m liking this rotary encoder idea, I’m thinking of adding an 8 button top panel, so freeing up buttons would be cool, maybe I’ll get another DAC one day. I think I tinker with this thing more than I play it!