Matt,
Uptone uses the LTM4607 as the charging DC-DC converter for their LPS-1.2 version, which gives them additional flexibility in the energizing supply.
I was referring to the devices they use to connect / isolate the banks of Ultracaps to / from the energizing supply / output load. They didn't use relays (which Vinnie Rossi used to use) for reliability reasons and noise. They didn't use MOSFETs because the high-ish off capacitance allows feed-through of some noise from the energizing supply if it uses an SMPS. What they do use are selected low-off-capacitance transistors, moving to an even lower C one for the 1.2 version for greater isolation for 'high-source-impedance leakage currents'.
Greg in Mississippi
Ian,
I've been following this thread (and the Katana thread) for some time - some very interesting stuff in here! Which of the things discussed are actually available? Are the 9028/9038 DAC's available? Is the Isolator/FIFO reclocker available (I currently use an IsolatorPi with the Allo Kali/Piano 2.1)? Very interested in the progress with the Ultracap PSU's too and the control side of things...
Si
I've been following this thread (and the Katana thread) for some time - some very interesting stuff in here! Which of the things discussed are actually available? Are the 9028/9038 DAC's available? Is the Isolator/FIFO reclocker available (I currently use an IsolatorPi with the Allo Kali/Piano 2.1)? Very interested in the progress with the Ultracap PSU's too and the control side of things...
Si
Beautiful, great building Ian,thank for the photo.
@SonofThor & @folzag,
Much of it is in development & alpha testing right now, with a few products available in Ian's last group buy.
Status (as I understand them... Ian may have some additional info):
RPi DAC cards... Initial ES9018K2M board with on-board output stage superceded by initial ES9028Q2M board with plug-in output stages, used for output transformer & I/V stage trials. ES9038Q2M & dual mono ES9038Q2M boards in prototype stage, future releases.
RPi DAC output stage cards... Generic transformer output stage proto-board in-use for trials of various output transformers, once one is chosen as good cost effective choice a board designed for that transformer is expected. Possibly Lundahl LL1544A? OPA861 & OPA1632 boards in prototype stages. All possible future release after listening trials.
UC Pi (Ultracap RPi DAC power supply)... Prototype running, additional prototypes expected soon, likely will grow into a more sophisticated unit after trials, future release after x development cycles.
ESS DAC controller... prototypes operational and working well, handles at least ES9018K2M, ES9038Q2M, ES9028Q2M, and possibly more, future release.
RPi I2S output board... Rev 1 available in last group buy, Rev 2 designed & prototyped to accommodate interface to ESS DAC controller, future release.
IsolatorPi... Rev 1 available in last group buy, Rev 2 designed & prototyped with additional features, future release.
DOP to DSD decoder... works on IsolatorPi, available in last group buy.
FIFOPi (integrated isolator / FIFO reclocker / clock board)... in development, future release. Ian may have mentioned it also includes the DOP to DSD decoder functionality, but I may be wrong on that.
LT3042 regulator boards... prototypes in-use on the DAC boards and the UCPi, future release.
I've been honored to be an Alpha tester for some of Ian's great designs and have used some of his other designs (such as his I2S FIFO setup) in some of my gear builds, they've been some great additions to my collection of digital playback setups.
Greg in Mississippi
P.S. How'd I do, Ian?
Much of it is in development & alpha testing right now, with a few products available in Ian's last group buy.
Status (as I understand them... Ian may have some additional info):
RPi DAC cards... Initial ES9018K2M board with on-board output stage superceded by initial ES9028Q2M board with plug-in output stages, used for output transformer & I/V stage trials. ES9038Q2M & dual mono ES9038Q2M boards in prototype stage, future releases.
RPi DAC output stage cards... Generic transformer output stage proto-board in-use for trials of various output transformers, once one is chosen as good cost effective choice a board designed for that transformer is expected. Possibly Lundahl LL1544A? OPA861 & OPA1632 boards in prototype stages. All possible future release after listening trials.
UC Pi (Ultracap RPi DAC power supply)... Prototype running, additional prototypes expected soon, likely will grow into a more sophisticated unit after trials, future release after x development cycles.
ESS DAC controller... prototypes operational and working well, handles at least ES9018K2M, ES9038Q2M, ES9028Q2M, and possibly more, future release.
RPi I2S output board... Rev 1 available in last group buy, Rev 2 designed & prototyped to accommodate interface to ESS DAC controller, future release.
IsolatorPi... Rev 1 available in last group buy, Rev 2 designed & prototyped with additional features, future release.
DOP to DSD decoder... works on IsolatorPi, available in last group buy.
FIFOPi (integrated isolator / FIFO reclocker / clock board)... in development, future release. Ian may have mentioned it also includes the DOP to DSD decoder functionality, but I may be wrong on that.
LT3042 regulator boards... prototypes in-use on the DAC boards and the UCPi, future release.
I've been honored to be an Alpha tester for some of Ian's great designs and have used some of his other designs (such as his I2S FIFO setup) in some of my gear builds, they've been some great additions to my collection of digital playback setups.
Greg in Mississippi
P.S. How'd I do, Ian?
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Hi Greg
Just interested if you have managed to assemble the UCPi power supply as yet and if so, what are your impressions?
Thanks
Just interested if you have managed to assemble the UCPi power supply as yet and if so, what are your impressions?
Thanks
@marcus1, after the boards arrived, I needed to go over the documentation from Ian and get the appropriate parts ordered. They are here, will be assembling and setting them up for tests this week and weekend. They'll be sharing my bench and system time with a new Allo.com Katana which also just arrived for trials.
@smoothquark, I cannot speak for what Ian plans to do to enhance and extend the functionality of his controller, but AFAIK, it is currently implemented to act as a direct controller of the ESS DAC and does not interface or communicate with any drivers on the RPi. Ian may chime in and correct me, but that is how I believe it is functioning as of today. It does control the volume via the volume control functionality ESS built into their DAC chips and does so very well, both with the on-board rotary controller AND via IR remote.
Greg in Mississippi
@smoothquark, I cannot speak for what Ian plans to do to enhance and extend the functionality of his controller, but AFAIK, it is currently implemented to act as a direct controller of the ESS DAC and does not interface or communicate with any drivers on the RPi. Ian may chime in and correct me, but that is how I believe it is functioning as of today. It does control the volume via the volume control functionality ESS built into their DAC chips and does so very well, both with the on-board rotary controller AND via IR remote.
Greg in Mississippi
Dietpi has a linux alsa driver for ESS. So far I haven't been able to get it to adjust volume... seems to be one of two states...on or off... and nothing in between. Ymmv.
DietPi - Lightweight justice for your SBC
http://essabre-90xx-rpi.sfb2.com/wp-content/uploads/2018/05/Bildschirmfoto_2018-05-05_19-28-51.png
@smoothquark,
I suspect Ian's controller could be made to work via ALSA with an appropriate driver. BUT I don't believe that has been done. AND of course, it has to make its way through the various distros before you can use it unless you are sufficient Linux-tech-aware to compile it yourself.
Greg in Mississippi
I suspect Ian's controller could be made to work via ALSA with an appropriate driver. BUT I don't believe that has been done. AND of course, it has to make its way through the various distros before you can use it unless you are sufficient Linux-tech-aware to compile it yourself.
Greg in Mississippi
yep. I think all idea of separate controller was to be independent and get rid of this all various distros and ALSA drivers hassle.
I don't think there can technically (legally) exist an open source driver for talking to the ESS chips directly. Their datasheets, which contain the I2C instructions for volume control (and filter selection,e tc) are only available under NDA. Pretty sure those details are supposed to remain private.
For their Katana DAC, Allo also created an intermediary circuit, conceptually similar to Ian's driver board. The Linux open-source drivers for the Allo device will talk to that intermediate chip, which in turn sends the real I2C commands to the ESS chip.
That said, I've seen people post ESS I2C code on their blogs. I believe this is technically a violation, though I'm not sure if ESS is actively pursuing these guys.
For their Katana DAC, Allo also created an intermediary circuit, conceptually similar to Ian's driver board. The Linux open-source drivers for the Allo device will talk to that intermediate chip, which in turn sends the real I2C commands to the ESS chip.
That said, I've seen people post ESS I2C code on their blogs. I believe this is technically a violation, though I'm not sure if ESS is actively pursuing these guys.
Hi guys,
With my ESS controller, you will be able to access the ESS hardware volume control through all linux distributions such as Volumio, piCorePlayer, moOde and so on, as long as the ALSA hardware volume control is enabled.
This has been done at finial version PCB. That's why Greg doesn't have this feature with the ESS controller I sent to him earlier.
Regards,
Ian
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That's a driver for the Audiophonics DAC as I see it. It's proprietary.
Like the Allo Katana driver, the Audiphonics driver doesn't control the DAC chip, it controls the on-DAC-MCU that controls the DAC chip. These drivers won't work on any other ESS DACs.
Just to mention it: That Audiophonics driver is not part of the official RPI kernel. Therefore DietPi is in charge (and taking any associated risks)!
Enjoy.
That's nice.
Alsa HW control doesn't have to be enabled though. It's just there if the driver supports it.
You need to explicitely configure squeezelite or MPD to use it though.
For squeezelite option "-V <control>" is required.
Typing "amixer" will list the controls as being offered by the driver.
E.g.
Code:
sc@nuc:~$ amixer
Simple mixer control 'Master',0That means for above example
"-V Master"
would to be the option of choice to be used with squeezelite.
I don't know how the control is called for Ians DAC, since I don't own that DAC.
BTW.
How are the on-dac-filters controlled ?