Did you make the relay boards yourself? Or are these boards available off-the-shelf?
Self designed and produced by PCBWay in China. Excellent quality and service from PCBWay.
Yes, a choke input with a big choke will give a sound which sound very easily like my new power supply for a drd tube power amp. Greetings, Eduard
Attachments
I agree. Sometimes it is matching, and sometimes things just sound bad whatever you connect it to. You cannot make a racehorse out of a donkey
Is there any chance that you share the design with us?
I'm in need of a premp, but I think the most efficient way with the DDDAC is Sowter's TVC.
Hmm. Do the trannies of the Octave out and the Sowter input interact with each other? Oscillation or similar issues?
I ran into such issues when I tried feeding the Sowter output into a passive x-over filter circuit. The complex impedances of the tranny and the caps didn't play well together.
Sure, see attached schematics. One IN_Relay board and two stacked TVC_Relay_14 boards required per implementation. The .zip file contains the schematics, PCB layout and Arduino code.
I actually have a spare set of boards which I might be persuaded to part with. PCBWay's minimum order is 5 boards per PCB design. In fact, PCBWay's minimum order and size/cost ratios were a deciding factor in using a stacked implementation for the TVC relay board.
Please note that this implementation was specifically designed for my own use in my own systems and therefore may not correspond to what you require. For example, it only has three input selectors; the code is targeted at an Arduino MEGA2560 board just because I happened to have one lying around; and cost of components weren't considered to be particularly significant.
Also please note that the information in the attachments if for DIY use only and not for commercial use.
Doede@
Have you the 7810 regs installed in your personal dac ? I’m asking because yesterday I removed them and lover the voltage to 10v at input mainboard. In my setup this is a huge upgrade, I am very impressed by your dac without this pre-regulation. I understand you want a safe constructed dac, but I will keep the regs out, as the sound is so much better after removing them.
Have you the 7810 regs installed in your personal dac ? I’m asking because yesterday I removed them and lover the voltage to 10v at input mainboard. In my setup this is a huge upgrade, I am very impressed by your dac without this pre-regulation. I understand you want a safe constructed dac, but I will keep the regs out, as the sound is so much better after removing them.
No clue, something about gain structure maybe. Octave is very punchy, guite opposite SPEC.
But let’s talk about ddac and how to squeeze more hifi juice out of it.
I've run many DDDACs with 12v going direct to the Tent shunts and had no reliability issues.tbh 2v is a tight margin for the shunts and 4v is better and well within soec.ymmv
Just to make sure - it is not only about reliability. One wrong voltage applied to the dac and your boards are dead. Not EVERY DDDAC DIY out there is top notch on electronics - so the 7810 are there for safety first.
secondly, 2 volt is more than enough- This is specially designed by me and Guido for the DDDAC, so not sure why you state that 2 Volt is tight? it is not... trust me, all components are in the middle of their linear bias points...
thirdly, with >12 Volts you are driving the parts towards the limit of their thermal specs. That might be ok in individual cases, but I cannot guruantee a safe design for the long run without knowing every single situation
hence, everyone is free to experiment - if you are not sure what you are doing, let the 7810 in, if you like them out, lower the supply voltage. If know what you are doing, well I am good of course
yes, no more off topic on pre amplifiers and relay boards please. interesting, but open own topics if we need more discussion please ! thanks
I have them in... and still impressed by the dac
I know some leave them out, no problems with that. The concept of DDDAC was and is to have room for tweaking and experiments
on "huge", that is personal of course. Me, I am a bit more holding back on the SQ improvements. If I would add up all the "huge" improvements over time, the original DAC must have been a shower radio, haha!
But that is not exclusive to the DDDAC, reading other topics or audio magazines. I understand and appreciate enthusiasm of DIY, when tweaks give nice improvements. It is up to every individual how to describe their experience of course
Hello,
Anyone who will decide to remove the 7810 regulators will be biased in a certain way because they read it will be spectaculair.
Once i used a Tent shunt in combination with a choke input supply. In installed a bleeder to make sure that there was a minimum current but i still was not sure. Guido Tent told me i could install a big zenerdiode across the power supply cap to keep the voltage under the maximum input of his circuit. Because during normal conditions the voltage is lower than the value of the zener it will not have an influence on the sound.
I use this trick in my DDDAC supply too BUT to protect the 7810 because i have an LCLCLC supply that will give a much higher DC voltage when only the bleeder across the first capacitor is working.
SO if the Tent shunt needs a minimum of 10 volts you could compose an 11 volt zener and take care that the average voltage during the day will be 10 volts coming from your diy supply.
I guess you have to take apart the DDDAC tower to get access to remove the 7810
Greetings,. eduard
Anyone who will decide to remove the 7810 regulators will be biased in a certain way because they read it will be spectaculair.
Once i used a Tent shunt in combination with a choke input supply. In installed a bleeder to make sure that there was a minimum current but i still was not sure. Guido Tent told me i could install a big zenerdiode across the power supply cap to keep the voltage under the maximum input of his circuit. Because during normal conditions the voltage is lower than the value of the zener it will not have an influence on the sound.
I use this trick in my DDDAC supply too BUT to protect the 7810 because i have an LCLCLC supply that will give a much higher DC voltage when only the bleeder across the first capacitor is working.
SO if the Tent shunt needs a minimum of 10 volts you could compose an 11 volt zener and take care that the average voltage during the day will be 10 volts coming from your diy supply.
I guess you have to take apart the DDDAC tower to get access to remove the 7810
Greetings,. eduard
price increase? no...
Quick comment - there are no price increases.
if you use a shop basked with old cookies, this might happen.
but more important, the shop uses IP addresses to see if you have to pay VAT. so sometimes it happens, when you are using VPN through other countries, which is very popular these days, your shop content might be wrong !!
or...…… if you are traveling and are in a different country…..
please check this also upfront (also other webshops will show similar issues…)
Quick comment - there are no price increases.
if you use a shop basked with old cookies, this might happen.
but more important, the shop uses IP addresses to see if you have to pay VAT. so sometimes it happens, when you are using VPN through other countries, which is very popular these days, your shop content might be wrong !!
or...…… if you are traveling and are in a different country…..
please check this also upfront (also other webshops will show similar issues…)
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anyone tried theese new class D regulators instead of LF50 and LT3045 on the MB?
NewClassD Regulator, DX7805 +5V UWB2 Regulator MK 2 | Hifi Collective
NewClassD Regulator, DX7805 +5V UWB2 Regulator MK 2 | Hifi Collective