Thanks for the search tip as helped me a lot 🙂
Looking forward to see your circuit and how you used the choke in the design
Hi Enrico,
Planning to build one board DDDAC with the new version boards from Doede. Is there any buffer board and smd parts left available?
Thanks,
Ken
Planning to build one board DDDAC with the new version boards from Doede. Is there any buffer board and smd parts left available?
Thanks,
Ken
Hi Ken,
I should have few PCBs left. For the parts I will check tonight when I back home ad let you know.
Best Regards,
Enrico
I should have few PCBs left. For the parts I will check tonight when I back home ad let you know.
Best Regards,
Enrico
Hi Ken,
I am sorry but I don't have the matched jfets. You can ask carlsor, maybe he still have some set available
Best Regards,
Enrico
I am sorry but I don't have the matched jfets. You can ask carlsor, maybe he still have some set available
Best Regards,
Enrico
Hello guys,
I just got some 8v tentlabs shunt regulators, after installing them I measure about 4.5 dc one side and 4.6 dc the other side. The sound as a result is quite distorted. I redid most if not all joins and read the tentlabs pdf, as far as I can tell the wiring is correct. The psu is the the one from the kit powering the motherboard and one dac board with shunts, it powered four boards before I installed these shunts. Varying input v also changed nothing and is set at about 12v, 11v at shunt input.
Was wondering if anyone had any ideas 🙄:confused
Regards,
I just got some 8v tentlabs shunt regulators, after installing them I measure about 4.5 dc one side and 4.6 dc the other side. The sound as a result is quite distorted. I redid most if not all joins and read the tentlabs pdf, as far as I can tell the wiring is correct. The psu is the the one from the kit powering the motherboard and one dac board with shunts, it powered four boards before I installed these shunts. Varying input v also changed nothing and is set at about 12v, 11v at shunt input.
Was wondering if anyone had any ideas 🙄:confused
Regards,
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I'd remove them from a DAC deck and then connect them to a power supply with "simple" load... a few watts resistor of some 200 ohms or something similar.
Allright, thanks.
Measuring between out and ground yields ~8.2v, so they seem fine... only had a 68r lying around, with it as load or just the multimeter in between both yield the same voltage. I mustve screwed something else up.
Tomorrow Ill go over the joins again and maybe try a different dac board.
Regards,
Measuring between out and ground yields ~8.2v, so they seem fine... only had a 68r lying around, with it as load or just the multimeter in between both yield the same voltage. I mustve screwed something else up.
Tomorrow Ill go over the joins again and maybe try a different dac board.
Regards,
The next few things I'd check are:
1. Is the input voltage at least 10V DC?
2. Is the impedance the shunts need to "drive" too low, i.e. maybe you have a short somewhere as seen by shunts' output.
Good luck,
Nick
1. Is the input voltage at least 10V DC?
2. Is the impedance the shunts need to "drive" too low, i.e. maybe you have a short somewhere as seen by shunts' output.
Good luck,
Nick
Well, tried another board. Same results. Input voltage from 11 to 14 same results. Disconnecting one side's regulator had no effect on the other. I could not find any shorts. Music plays, just distorted. Between the out pin and ground still measures 4.6volts pretty steadily.
My vcom caps are 47uf the big one close to the regulator is 100uf and the biggest one is 220uf. My rload is 135/136r. Could that cause the distortion? these values worked before.
I was afraid an ESD might've killed both chips on the other board, so I was extra careful with this one..
Tomorrow I'll try the other regulators, doubt they are the problem since I measured the ones that are installed right now, but can't hurt to test.
regards,
My vcom caps are 47uf the big one close to the regulator is 100uf and the biggest one is 220uf. My rload is 135/136r. Could that cause the distortion? these values worked before.
I was afraid an ESD might've killed both chips on the other board, so I was extra careful with this one..
Tomorrow I'll try the other regulators, doubt they are the problem since I measured the ones that are installed right now, but can't hurt to test.
regards,
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Allright, I've found the problem. My shunt board looks exactly like the one in post #3759 from the original thread. It seems I need a 30 ohm resistor to configure this shunt for the chip's current.
Post #3756 from that thread also describes the problem.
Thanks again for the suggestions Nick! 🙂
Regards,
Post #3756 from that thread also describes the problem.
Thanks again for the suggestions Nick! 🙂
Regards,
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Hi All,
Absolutely loving the DDDAC 1794, Im addicted to just sitting and listening to music again
Just some questions if anyone has any knowledge / experience:
1) I am using Cinemags for my output. I am feeding a Hypex NC400 amp with an input impedance of 104k. I am there using load resistors of 15k on the Cinemag outputs (giving me a total of 13k load). At the moment I am just using very cheap ebay resistors for this task. Does the quality of the resistor affect the output at all? I mean from an electronic perspective, does that load resistor affect the quality of the analog signal?
2) I have 4 decks with an output impedance of 34ohm, which is great as the amp's input is 104k. However, I saw some nice looking Diamond Buffer boards (Sjöström Audio - SSB01 Sjöström Super Buffer - Diamond buffer)
Would I benefit (sound-wise) from building these buffers between the DDDAC and the Cinemags? When is the best situation to use diamond buffers?
Thanks all!
Absolutely loving the DDDAC 1794, Im addicted to just sitting and listening to music again
Just some questions if anyone has any knowledge / experience:
1) I am using Cinemags for my output. I am feeding a Hypex NC400 amp with an input impedance of 104k. I am there using load resistors of 15k on the Cinemag outputs (giving me a total of 13k load). At the moment I am just using very cheap ebay resistors for this task. Does the quality of the resistor affect the output at all? I mean from an electronic perspective, does that load resistor affect the quality of the analog signal?
2) I have 4 decks with an output impedance of 34ohm, which is great as the amp's input is 104k. However, I saw some nice looking Diamond Buffer boards (Sjöström Audio - SSB01 Sjöström Super Buffer - Diamond buffer)
Would I benefit (sound-wise) from building these buffers between the DDDAC and the Cinemags? When is the best situation to use diamond buffers?
Thanks all!
Hi there!
1) I tried a few different types, they change the sound somewhat I guess imo. I have a carbon film resistor in there now. Imo it's not as critical as the rload.
2) I think the buffer talked about in this thread is to drive the cinemags with a singleboard. I wouldn't go this route, because I think there is little benefit when you already have four boards. But if the investment is small, one can always try right? Or maybe fully upgrade one deck with new caps and shunt regulators and add the buffer, convert it to an over the top singleboard dddac. I converted my four boards to an upgraded two decks this way, always looking to butcher things 😛 can't sit still!
1) I tried a few different types, they change the sound somewhat I guess imo. I have a carbon film resistor in there now. Imo it's not as critical as the rload.
2) I think the buffer talked about in this thread is to drive the cinemags with a singleboard. I wouldn't go this route, because I think there is little benefit when you already have four boards. But if the investment is small, one can always try right? Or maybe fully upgrade one deck with new caps and shunt regulators and add the buffer, convert it to an over the top singleboard dddac. I converted my four boards to an upgraded two decks this way, always looking to butcher things 😛 can't sit still!
Hello to all,
I don't question that Cinemags is one of the best transformers out there for the DDAC, but for now, to me is to expensive, so I've found the 140 EX series from Hammond that I can obtain for half the price of the Cinemags. Hammond Mfg. - Studio Grade - Impedance Matching - Audio Transformers - (140 "EX" Series)
Looking at their models, I suspect that the closest to Cinemags 15/15B is the UEX model-please correct me if I am wrong.
In this topic users are recommending to use a buffer to drive the Cinemags, I suspect that the reason is to match the 133 ohm impedance of the DAC to the input impedance of the Cinemags-again correct me if I am wrong.
If that is true, using a lower impedance transformer like the PEX, with primary in parallel to obtain a 150ohm impedance (closser to 133ohm DAC's imepdance) and secondary in series to obtain 2,4k output impedance[closser to minimmum 1:10 ratio recomanded for connection between amp(mine has 20k input impedance) and source] , means that I can skip de buffer? If not, the PEX is still a better choice that the UEX? or other EX model?
Thank you !
I don't question that Cinemags is one of the best transformers out there for the DDAC, but for now, to me is to expensive, so I've found the 140 EX series from Hammond that I can obtain for half the price of the Cinemags. Hammond Mfg. - Studio Grade - Impedance Matching - Audio Transformers - (140 "EX" Series)
Looking at their models, I suspect that the closest to Cinemags 15/15B is the UEX model-please correct me if I am wrong.
In this topic users are recommending to use a buffer to drive the Cinemags, I suspect that the reason is to match the 133 ohm impedance of the DAC to the input impedance of the Cinemags-again correct me if I am wrong.
If that is true, using a lower impedance transformer like the PEX, with primary in parallel to obtain a 150ohm impedance (closser to 133ohm DAC's imepdance) and secondary in series to obtain 2,4k output impedance[closser to minimmum 1:10 ratio recomanded for connection between amp(mine has 20k input impedance) and source] , means that I can skip de buffer? If not, the PEX is still a better choice that the UEX? or other EX model?
Thank you !