To be honest, I wouldn't recommend the jumper because it would be easy mess up. I would try the ProtoDac just on top of the raspberry pi to get it working that way until you can set it up with the gpio spacer and the 5v supply for the fifopi. hifiamps has solid advice and provided info to get it work with great detail.
With the PurePi, the 5V supply is from the ultracapacitors (100F in series), and the 3.3V supply is from the LiFePO4 batteries (two in parallel). So when the stack on the PurePi is RPi/Q7/DAC HAT on the isolated GPIO, the Q7 and DAC are powered by the batteries, and the RPi is powered by the ultracapacitors. That is a complete waste of expensive ultracapacitors.
The stacking header (with pins 2 and 4 removed) between Q7 and ProtoDAC seems to be a necessity. Then power ProtoDAC with the 5V (J6). I also think getting the RPi off the PurePi power pins (use taller standoffs) and use its own supply, so it isn't sharing the ultracapacitor supply with ProtoDAC.
The stacking header (with pins 2 and 4 removed) between Q7 and ProtoDAC seems to be a necessity. Then power ProtoDAC with the 5V (J6). I also think getting the RPi off the PurePi power pins (use taller standoffs) and use its own supply, so it isn't sharing the ultracapacitor supply with ProtoDAC.
@hifiamps
"The stacking header (with pins 2 and 4 removed) between Q7 and ProtoDAC seems to be a necessity. Then power ProtoDAC with the 5V (J6). I also think getting the RPi off the PurePi power pins (use taller standoffs) and use its own supply, so it isn't sharing the ultracapacitor supply with ProtoDAC."
Great idea, Mark !
So, a better scheme would be :
Did I understand well ? (short lunch pause at work 😉 )
"The stacking header (with pins 2 and 4 removed) between Q7 and ProtoDAC seems to be a necessity. Then power ProtoDAC with the 5V (J6). I also think getting the RPi off the PurePi power pins (use taller standoffs) and use its own supply, so it isn't sharing the ultracapacitor supply with ProtoDAC."
Great idea, Mark !
So, a better scheme would be :
- Separate RPI ( stacked on PurePi without power.) powered by own PS (official RPI or iFi ?)
- Q7 (stacked on RPI with pins 2 and 4 removed ) powered by PurePi ( 3.3V from PurePI J2)
- ProtoDAC powered by UC PurePI through Q7 J3 and soldered wires between Q7 and ProtoDAC
Did I understand well ? (short lunch pause at work 😉 )
Not quite.
2. Q7 stacked on the RPi GPIO. Q7 is powered from the 3.3V supply of PurePi (J2) using the standard jumper wires.
3. ProtoDAC stacked on the isolated GPIO of Q7 using a stacking header with pins 2 and 4 removed. Use jumper wires from PurePi 5V terminals (J6) to ProtoDAC 5V and GND pads.
2. Q7 stacked on the RPi GPIO. Q7 is powered from the 3.3V supply of PurePi (J2) using the standard jumper wires.
3. ProtoDAC stacked on the isolated GPIO of Q7 using a stacking header with pins 2 and 4 removed. Use jumper wires from PurePi 5V terminals (J6) to ProtoDAC 5V and GND pads.
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The use of the stacking header makes for a reversible solution for the Ian Canada reclocker problem.
For an irreversible solution, just remove pins 2 and 4 from the ProtoDAC GPIO header (before soldering). That way you always need to power ProtoDAC using the 5V and GND pads. It will also sit lower on Q7. I still can't find short stacking headers.
For an irreversible solution, just remove pins 2 and 4 from the ProtoDAC GPIO header (before soldering). That way you always need to power ProtoDAC using the 5V and GND pads. It will also sit lower on Q7. I still can't find short stacking headers.
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I do this right now and cross the fingers. I'll post when I am done.
(Éric is going to order ProtoDAC tomorrow - hope so)
1. homework done. PurePi, RPI (powered from PurePi springs), Q7 (powered by PurePI J2), ProtoDAC (powered by J6 PurePi to 5V and GND pads, GPIO pins 2 and 4 removed). Nothing. PurePi can't power the stack.
2. RPI+ProtoDAC powered by RPI GPIO (first setup when I received ProtoDAC) => great, as usual (ProtoDAC is fine)
3. PurePi, RPI (powered separately, with higher standoffs), Q7 (powered by PurePI J2), ProtoDAC (powered by J6 PurePi to 5V and GND pads, stacking header GPIO pins 2 and 4 removed) => 30sec with great sound, then PurePI stops to supply.
Any clue ?
Let's charge all night long. I will check tomorrow and post the result.
2. RPI+ProtoDAC powered by RPI GPIO (first setup when I received ProtoDAC) => great, as usual (ProtoDAC is fine)
3. PurePi, RPI (powered separately, with higher standoffs), Q7 (powered by PurePI J2), ProtoDAC (powered by J6 PurePi to 5V and GND pads, stacking header GPIO pins 2 and 4 removed) => 30sec with great sound, then PurePI stops to supply.
Any clue ?
Let's charge all night long. I will check tomorrow and post the result.
The charging power supply needs to be plugged in.
3. The ultracapacitors have completely discharged, and PurePi stops. Plug in the charging supply to keep the ultracapacitors charged.
PurePi diagram:
Charging supply---->LiFePO4 batteries--->3.3V
Charging supply---->Ultracapacitors----->5V
3. The ultracapacitors have completely discharged, and PurePi stops. Plug in the charging supply to keep the ultracapacitors charged.
PurePi diagram:
Charging supply---->LiFePO4 batteries--->3.3V
Charging supply---->Ultracapacitors----->5V
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The OP really has a nice setup.
I am now using a power bank instead of the charging SMPS. Yes, it has a boost converter, so still some switching noise. Maybe a 2S LiPO or LiFePO4 battery pack with linear regulator in place of the charging SMPS. Yes, some inefficiency and heat loss from the linear regulator, but quiet.
I am now using a power bank instead of the charging SMPS. Yes, it has a boost converter, so still some switching noise. Maybe a 2S LiPO or LiFePO4 battery pack with linear regulator in place of the charging SMPS. Yes, some inefficiency and heat loss from the linear regulator, but quiet.
Hello,
I have recently built a streamer, based on Ian Canada components, incl. FifoPi Q7, TransportPi AES, and lots of power conditioning with linear power supplies and ultracapacitors (see photo). I am now waiting for the StationPi Pro to finish the streamer, by separating the RPi from the FifoPi Q7 and the TransportPi AES. Having watched Gabster’s review of the ProtoDac, and being a fan of NOS-R2R DACs, I am interested in adding a ProtoDac on my streamer stack.
I assume that I can remove the TransportPi AES and replace it with the Protodac (on top of the FifoPi Q7, which has a 5V power from the GPIO and 3.3V from the UCconditioners). Can someone please confirm that's a correct way to connect the ProtoDac?
Furthermore, I live in Europe (Greece) and I wonder whether I can find the ProtoDac kit or a fully assembled ProtoDac anywhere in the European Union, so that I avoid any delays and any import duties with the Greek customs, if I buy from USA. Maybe you can give me some advice on where I may find the ProtoDac that I am looking for?
I have recently built a streamer, based on Ian Canada components, incl. FifoPi Q7, TransportPi AES, and lots of power conditioning with linear power supplies and ultracapacitors (see photo). I am now waiting for the StationPi Pro to finish the streamer, by separating the RPi from the FifoPi Q7 and the TransportPi AES. Having watched Gabster’s review of the ProtoDac, and being a fan of NOS-R2R DACs, I am interested in adding a ProtoDac on my streamer stack.
I assume that I can remove the TransportPi AES and replace it with the Protodac (on top of the FifoPi Q7, which has a 5V power from the GPIO and 3.3V from the UCconditioners). Can someone please confirm that's a correct way to connect the ProtoDac?
Furthermore, I live in Europe (Greece) and I wonder whether I can find the ProtoDac kit or a fully assembled ProtoDac anywhere in the European Union, so that I avoid any delays and any import duties with the Greek customs, if I buy from USA. Maybe you can give me some advice on where I may find the ProtoDac that I am looking for?
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@pkonstantinidis beautiful setup !
I bought the ProtoDAC (after seeing @Gabster 2000 review too from Mark @hifiamps from USA.
I bought the ProtoDAC (after seeing @Gabster 2000 review too from Mark @hifiamps from USA.
@MaxB_70 So, what's your impression of the ProtoDAC?
In my case, I think it would be a simple addon on the FifoPi Q7 and I will have a fully functioning DAC (unless I am missing something).
My only concern is that the ProtoDAC is reducing any higher bit music (e.g. 24bit) to 16bit. I do not know whether that has any adverse effects on the sound quality...
In my case, I think it would be a simple addon on the FifoPi Q7 and I will have a fully functioning DAC (unless I am missing something).
My only concern is that the ProtoDAC is reducing any higher bit music (e.g. 24bit) to 16bit. I do not know whether that has any adverse effects on the sound quality...
2 chargers are plugged in : 3A@5V to RPI, 5A@5V to PurePI.
when S2 PurePi is off, Q7 D2 LED is brighting. I don't know why.
Music during 30s then PurePI stops. I will post videos.
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I haven't big experience with DAC streamers. I owned a usb DAC (Encore mDCD) plugged on an Apple laptop with Audirvana software during 5 years and a Wiim Pro during few months. The music from the ProtoDAC is much better than both sources above. It is realistic and fun approaching my favorite source which is a Lenco L75 TT with heavy plinth, air bearing arm, big cell (a very nice analogical source), even lonely stacked on RPI.
A friend of mine has a Cary streamer DAC. We both prefer ProtoDAC.
The FifoPi give quietness, bigger bandwidth and tight bass, soundstage deeper and wider.
seems Q7 supplied by RPI !! on the picture, wires not plugged on Q7 3.3V jumpers but D2 brights. Is that supposed to happen ?
answer to myself : 5V from RPI GPIO because Q7 is supposed to supply if needed 5V through J3.
