No my bad, it was said that it maybe ok for 9038q2m chinese board depending of opamp used.
ES9038Q2M Board
@Markw4,
I agree that the opamps will work ok on +-12V. The Sparkos are rated for +-6V to +-18V, with an absolute max of +-22V. BUT I'm not sure those +-14V regulators will pass the +-12V to their outputs and IF they do, since they are not in regulation, I'm not sure how much they will degrade the +-12V in voltage, available current, added noise, and additional series resistance. They may pass the +-12V ok. BUT in my experience, they won't.
Greg in Mississippi
I agree that the opamps will work ok on +-12V. The Sparkos are rated for +-6V to +-18V, with an absolute max of +-22V. BUT I'm not sure those +-14V regulators will pass the +-12V to their outputs and IF they do, since they are not in regulation, I'm not sure how much they will degrade the +-12V in voltage, available current, added noise, and additional series resistance. They may pass the +-12V ok. BUT in my experience, they won't.
Greg in Mississippi
@alexkosha... noone has fess'd up to it yet. My opinion is that I bet they'd be spankin', right along with Super Regulators, the latest standard Salas, and my Sparkos setup (with alternatives of Belleson or Dexa UWB-2).
I have a couple almost built for 5V... if I get time, I'll finish them and try them.
Too many projects, too little time!
Greg in Mississippi
I have a couple almost built for 5V... if I get time, I'll finish them and try them.
Too many projects, too little time!
Greg in Mississippi
@cdsgames,
Thanks for the clarification that +-15V is the minimum +-voltage needed to separately power the output stages. Knowing that SOMEONE will ask this, I thought I'd get the jump on them... what is the MAXIMUM +-voltage that is acceptable for the +-15V feed?
Thanks!
Greg in Mississippi
Thanks for the clarification that +-15V is the minimum +-voltage needed to separately power the output stages. Knowing that SOMEONE will ask this, I thought I'd get the jump on them... what is the MAXIMUM +-voltage that is acceptable for the +-15V feed?
Thanks!
Greg in Mississippi
I personally would be very interested to get your opinion about Salas PSUs on Katana. I’m assembling all 4 PSUs now, but would be not able to make compassion. Have no other PSUs to compare to.
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.@Markw4, I've had similar thoughts on that. I use a CDE 100uF/800V polyprop cap prized by some Japanese audiophiles as a local 'smoother/sweetener' for some of my digital gear, such as my SDTrans384 SD card I2S player and Allo's Kali's. I've got 3-4 of them here. I'll have to make some adapters, but it'd be easy to put a couple of these in-line close to the Katana for some some SQ trials.
It'll likely be awhile before I get to this, my next post will outline some recent tests and some planned paths forward. BUT this will be a useful thing to try too at some point.
Greg in Mississippi
It'll likely be awhile before I get to this, my next post will outline some recent tests and some planned paths forward. BUT this will be a useful thing to try too at some point.
Greg in Mississippi
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Report on setups using modified Jameco 5V & 12V Linear Regulated Wall Warts
I spent some time last night listening to the Katana 5V Isolator output side / DAC board and Microprocessor boards powered with some lower-cost supplies that I thought might be interesting alternatives AND provide a comparison that provided some insight into the Katana performance with various levels of power supplies.
I provided some details on the Jameco mods and how I'd do these tests in posts # 19, 42, 60, & 82 upthread.
I used 2 alternative supply setups with each replacing the 2 5V supplies feeding the Katana 5V Isolator output side / DAC board and Microprocessor boards. They were:
1. 2 modified Jameco 5V/1A/5W linear regulated supplies.
2. 2 modified Jameco 12V/1A/12W linear regulated supplies, each feeding 1/2 of a dual 4||LT3042 regulator board that used to be available from DIYAudio poster OPC back a few years. MPAudio.net's MD-HPULN PS is roughly equivalent, but over time I've found I prefer the MPAudio unit to OPC's.
Other than substituting the above supplies in for those 2 feeds, I kept the other supplies (5V RPi / Isolator input side, +-15V Opamp board) the same as described as my 'best' power setup for the Katana, per post #4 upthread. Do read these impressions in that context, the rest of the supplies were still some of the best I've found for use with a Katana setup AND still more expensive than many would use.
Using the 2 5V/1A supplies with 1 each directly feeding the Katana DAC board and Microprocessor boards, I would rate the sound as 'basically competent'. This setup sounded a little better than I expected and I would rate the Katana with this supply as approaching the other best RPi DACs I've tried (ApplePi and my Hotrod-modified Dial DAC). Extension was good, detailing was good, but not great, dynamics didn't jump, but were not overall disappointing. All in all, a good substitute replacing $520 USD of DIY'd power supplies with roughly $45 USD including some DIY effort. An interesting future comparison will be how this setup compares to my 'best' setup, but with that configured to use the on-board +-15V DC-DC converters to power the opamp board and NOT using my separate linear +-15V supply.
Using the 2 12V/1A supplies, each into 1/2 of the 5V OPC dual 4||LT3042 boards and these feeding the Katana DAC board and Microprocessor boards, I would rate the sound as 'a hint of greatness'. All aspects of the sonics were improved and hints of the detailing, dynamics, bass and treble extension and definition that has me really excited about the Katana at its best emerged. DID this setup equal my best to my ears and in my setup... NOPE, not nearly. BUT it was a clear step up from the above and now above all RPi setups I've heard EXCEPT for the Katana at its best. Another good substitute replacing $520 USD of DIY'd power supplies with roughly $220 USD, again including some DIY effort.
Finally, I went back to my best supply setup. I heard again the aspects that have had me rave about the Katana at its best... very detailed and dynamic sound, with extension at both extremes as good as I've had in my systems. It approaches the 'lifelike' qualities I've heard from the best setups I've listened to ever in my audio hobby years. The sonics were above anything else I've heard from an RPi DAC and at the same level as my other 'best' digital sources. (Honestly, though I haven't done the head-to-head comparisons yet, I suspect when I do I will be looking at what I need to do to bring those setups up to the level of the Katana... if I can). I described those setups in post #19 and the sonics of the Katana at its best in my setup in post #35 in this thread and posts #2626 & 2640 in the main Allo thread.
For me at least this was instructive. The SQ jumps between the different options were roughly as I expected, based on other power supply trials and upgrades I've done in the past. YUP, the Katana can sound good with lesser power supplies, but with corresponding downgrades in SQ. YUP, improving the power supplies incrementally improve the Katana's SQ.
BTW, I am quite sure there are many steps above my 'best' setup. If Paul Hynes wasn't winding down his power supply business, I suspect one of his units purpose built with 4 separate supplies providing the 3 5V rails and the +-15V rails would both blow my meager amateur efforts out of the water and our minds at how much improvement is still available in this little DAC at a cost that would boggle most of us!
Next steps for this set of trials are to try the Jameco setups both powering the RPi / Isolator input side and to use a pair of the modified 12V/1A Jamecos to power the +-15V for the Opamp board in the following configurations:
1. Using the raw 19VDC from the 12V Jameco to feed the +-15V Sparkos regulators I use currently
2. Replacing the +-15V Sparkos with a +-15V-configured MPAudio MD-HPULN power supply
2. Replacing the +-15V Sparkos with a +-15V LT1963/LT3015 pair
3. Modifiying the voltage setting of the on-board regulator device of the Jameco (if that works ok) to output the 15VDC needed to directly feed the Opamp board
This all will take some weeks to setup as I acquire more Jamecos, modify them, and build-up another OPC dual 4||LT3042 regulator board setup AND the MD-HPULN. Oh, and work, pay the bills, observe the holidays, and work on some other pressing hobby projects.
In the meantime, over the next several days, I'll be listening to various combinations of Ian's UCPi Ultracap trial boards (2 325F/2.7V Ultracaps in series with an on-board current-limited charging regulator) powering the Katana 5V rails and the Ian prototype ES9028Q2M DAC stack's IsolatorPi and Kali reclocker. While my experience is that this type of setup works best when directly powering the active chips without intervening regulators, I promised @randytsuch I'd try these as alternatives to my more expensive 'best' Katana supply setup.
I've stated before I intend to do a blog post (likely on Computer Audiophile) outlining how to modify the Jamecos. It'll be a few months before I do that, at best, due to other projects as above and other commitments. In the meantime, I'll post the BOMs for the 4 varieties of mods I've done to them so far along a few more pictures so that enterprising experienced DIY'ers can duplicate this if they wish. I should be able to do this within the week.
Greg in Mississippi
P.S. I do understand that the modified Jameco supplies options are limited to North America. I wonder if there are equivalent supplies available for some of the other AC power regions... any tips on this?
I spent some time last night listening to the Katana 5V Isolator output side / DAC board and Microprocessor boards powered with some lower-cost supplies that I thought might be interesting alternatives AND provide a comparison that provided some insight into the Katana performance with various levels of power supplies.
I provided some details on the Jameco mods and how I'd do these tests in posts # 19, 42, 60, & 82 upthread.
I used 2 alternative supply setups with each replacing the 2 5V supplies feeding the Katana 5V Isolator output side / DAC board and Microprocessor boards. They were:
1. 2 modified Jameco 5V/1A/5W linear regulated supplies.
2. 2 modified Jameco 12V/1A/12W linear regulated supplies, each feeding 1/2 of a dual 4||LT3042 regulator board that used to be available from DIYAudio poster OPC back a few years. MPAudio.net's MD-HPULN PS is roughly equivalent, but over time I've found I prefer the MPAudio unit to OPC's.
Other than substituting the above supplies in for those 2 feeds, I kept the other supplies (5V RPi / Isolator input side, +-15V Opamp board) the same as described as my 'best' power setup for the Katana, per post #4 upthread. Do read these impressions in that context, the rest of the supplies were still some of the best I've found for use with a Katana setup AND still more expensive than many would use.
Using the 2 5V/1A supplies with 1 each directly feeding the Katana DAC board and Microprocessor boards, I would rate the sound as 'basically competent'. This setup sounded a little better than I expected and I would rate the Katana with this supply as approaching the other best RPi DACs I've tried (ApplePi and my Hotrod-modified Dial DAC). Extension was good, detailing was good, but not great, dynamics didn't jump, but were not overall disappointing. All in all, a good substitute replacing $520 USD of DIY'd power supplies with roughly $45 USD including some DIY effort. An interesting future comparison will be how this setup compares to my 'best' setup, but with that configured to use the on-board +-15V DC-DC converters to power the opamp board and NOT using my separate linear +-15V supply.
Using the 2 12V/1A supplies, each into 1/2 of the 5V OPC dual 4||LT3042 boards and these feeding the Katana DAC board and Microprocessor boards, I would rate the sound as 'a hint of greatness'. All aspects of the sonics were improved and hints of the detailing, dynamics, bass and treble extension and definition that has me really excited about the Katana at its best emerged. DID this setup equal my best to my ears and in my setup... NOPE, not nearly. BUT it was a clear step up from the above and now above all RPi setups I've heard EXCEPT for the Katana at its best. Another good substitute replacing $520 USD of DIY'd power supplies with roughly $220 USD, again including some DIY effort.
Finally, I went back to my best supply setup. I heard again the aspects that have had me rave about the Katana at its best... very detailed and dynamic sound, with extension at both extremes as good as I've had in my systems. It approaches the 'lifelike' qualities I've heard from the best setups I've listened to ever in my audio hobby years. The sonics were above anything else I've heard from an RPi DAC and at the same level as my other 'best' digital sources. (Honestly, though I haven't done the head-to-head comparisons yet, I suspect when I do I will be looking at what I need to do to bring those setups up to the level of the Katana... if I can). I described those setups in post #19 and the sonics of the Katana at its best in my setup in post #35 in this thread and posts #2626 & 2640 in the main Allo thread.
For me at least this was instructive. The SQ jumps between the different options were roughly as I expected, based on other power supply trials and upgrades I've done in the past. YUP, the Katana can sound good with lesser power supplies, but with corresponding downgrades in SQ. YUP, improving the power supplies incrementally improve the Katana's SQ.
BTW, I am quite sure there are many steps above my 'best' setup. If Paul Hynes wasn't winding down his power supply business, I suspect one of his units purpose built with 4 separate supplies providing the 3 5V rails and the +-15V rails would both blow my meager amateur efforts out of the water and our minds at how much improvement is still available in this little DAC at a cost that would boggle most of us!
Next steps for this set of trials are to try the Jameco setups both powering the RPi / Isolator input side and to use a pair of the modified 12V/1A Jamecos to power the +-15V for the Opamp board in the following configurations:
1. Using the raw 19VDC from the 12V Jameco to feed the +-15V Sparkos regulators I use currently
2. Replacing the +-15V Sparkos with a +-15V-configured MPAudio MD-HPULN power supply
2. Replacing the +-15V Sparkos with a +-15V LT1963/LT3015 pair
3. Modifiying the voltage setting of the on-board regulator device of the Jameco (if that works ok) to output the 15VDC needed to directly feed the Opamp board
This all will take some weeks to setup as I acquire more Jamecos, modify them, and build-up another OPC dual 4||LT3042 regulator board setup AND the MD-HPULN. Oh, and work, pay the bills, observe the holidays, and work on some other pressing hobby projects.
In the meantime, over the next several days, I'll be listening to various combinations of Ian's UCPi Ultracap trial boards (2 325F/2.7V Ultracaps in series with an on-board current-limited charging regulator) powering the Katana 5V rails and the Ian prototype ES9028Q2M DAC stack's IsolatorPi and Kali reclocker. While my experience is that this type of setup works best when directly powering the active chips without intervening regulators, I promised @randytsuch I'd try these as alternatives to my more expensive 'best' Katana supply setup.
I've stated before I intend to do a blog post (likely on Computer Audiophile) outlining how to modify the Jamecos. It'll be a few months before I do that, at best, due to other projects as above and other commitments. In the meantime, I'll post the BOMs for the 4 varieties of mods I've done to them so far along a few more pictures so that enterprising experienced DIY'ers can duplicate this if they wish. I should be able to do this within the week.
Greg in Mississippi
P.S. I do understand that the modified Jameco supplies options are limited to North America. I wonder if there are equivalent supplies available for some of the other AC power regions... any tips on this?
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I currently have some of Greg's modified Jamecos and one of his OPC regs in my system so I'll add my 2 cents. I don't have a Katana, but I have tested Greg's supplies on a half dozen other RPi DAC hats, so I have a good feel for their sound.
To my ears, Greg's 5V Jamecos are good workhorse supplies which sound much nicer than a "clean" switcher like the iPower (and yes, I tried the iPower with a shortened cable, gobs of capacitance right at the board, and a grounded negative terminal). In my system the Jamecos were quieter with less glare.
Two of Greg's 12V Jamecos into an OPC parallel quad LT3042 creates a supply that is better yet. The "hint of greatness" is not subtle. I am enjoying a vivid, glare-free, transparent tone. Too bad these modules are no longer available, but good to hear that the MPAudio version is even better!
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