This should be the right link.
AD1865N-K AD1865 18bit Audio DAC upgrade Audionote IC d - eBay (item 170459893465 end time Apr-14-10 22:02:12 PDT)
AD1865N-K AD1865 18bit Audio DAC upgrade Audionote IC d - eBay (item 170459893465 end time Apr-14-10 22:02:12 PDT)
How much for the full set ?
I joined this thread just recently and this DAC seems like just what I wanted so I ordered a full set of boards but I have no idea where in this big thread the details of the prices etc are.
I asked quanghao a couple of times how much I should send him but for some reason I did not get a reply . . . .
So I would be really gratefull if someone here can tell either the cost of a full set of boards including all extras or where in this thread this is explained
Many thanks
mike 🙂
I joined this thread just recently and this DAC seems like just what I wanted so I ordered a full set of boards but I have no idea where in this big thread the details of the prices etc are.
I asked quanghao a couple of times how much I should send him but for some reason I did not get a reply . . . .
So I would be really gratefull if someone here can tell either the cost of a full set of boards including all extras or where in this thread this is explained
Many thanks
mike 🙂
The cost is around 15 $ per board + shipping. There are three boards DAC, PS for DAC, and IV. You can add a Salas HV regulator if you want regulated DC of the IV. This makes a total of four boards.
D.
D.
google 'fake ad1865n-k' and you wont find much at all. basically i dont think anyone knows. the only source where you can be all but garanteed a genuine is digikey
Hi Adamus,
I'm back on this DAC for a little while as I'm working on a new SE amplifier.
As I said before I like your idea of replacing the cap with LED on I/V stage, but the LED IMO is not very linear. So I believe following you track try to use TLV431 instead of the LED... then let me know.... 🙂
It's linear from DC to 50KHz !!
I'm back on this DAC for a little while as I'm working on a new SE amplifier.
As I said before I like your idea of replacing the cap with LED on I/V stage, but the LED IMO is not very linear. So I believe following you track try to use TLV431 instead of the LED... then let me know.... 🙂
It's linear from DC to 50KHz !!
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I mean its frequency response is flat to near 50KHz and of course IMO there is no capacitor can reach that performance on cathode bias in this I/V stage
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~0.25 Ohms flat to 40KHz (according to the chart). Total dynamic impedance depends on external resistors. Am I right?
What about the LED dynamic impedance?
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I guess so, which would lead us back to having to bypass with a electrolytic cap. thats the beauty of the LED's, no bypassing.
Sorry I don't get it. Look at the first and second chart. Which one shows more dynamic impedance? LED looks more banana to me. Also I don't know what happens to the LED between DC and 50KHz.
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its so easy to try the mod, just go for it. 5 mins tops.
I have no idea how the tlv431 would behave in series (you would need to to get to 3.8v) and cant see that anyone has ever tried them. they could well work
MY guess is your electronics knowledge far outstrip mine, and we may be better to ask someone like Sy to comment, i dont want to get out my depth.
I have no idea how the tlv431 would behave in series (you would need to to get to 3.8v) and cant see that anyone has ever tried them. they could well work
MY guess is your electronics knowledge far outstrip mine, and we may be better to ask someone like Sy to comment, i dont want to get out my depth.
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Well I tried the function on a little headphone amp using a 9pin direct heater tube.
I could not believe my ears. Very deep bass and clean details. Amazing. After that I feel any good cap for bias could go in the bin.
I don't think I'm better then you and I'm just here to share knowledge for improvement. It was your idea anyway, I just wanted to dig more into it.
Of course we gain something and we loose something at the same time. The self bias function of the valve in this case is lost so we need to be careful about maintaining B+ stable or the working point goes banana. Self bias is very safe but we need gain. Sometime a nice resistor is not enough and we put the cap which on AC AF is pretty unlinear (down and up) so we gain "gain" and we loose performance of the sound.
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For this DAC I/V stage TL431 is more appropriate. I just had the TLV431 in my mind as I'm using in another project
I could certainly try it at some point.
I still havent picked up the power resistors to drop the B+ and allow a sensible CSS, i need to try that too.
cheers for the tips!
I still havent picked up the power resistors to drop the B+ and allow a sensible CSS, i need to try that too.
cheers for the tips!
Just for us newbies to this thread:
Could someone patiently re-list the link to order the boards?
Including the Salas HV regulator board?
I know we'll be reading and re-reading the whole thread... but a quick link re-listing pertinent reference links could help get newbies up to speed.
Thank you, all for a great thread-project-learning opportunity.
Could someone patiently re-list the link to order the boards?
Including the Salas HV regulator board?
I know we'll be reading and re-reading the whole thread... but a quick link re-listing pertinent reference links could help get newbies up to speed.
Thank you, all for a great thread-project-learning opportunity.
I will try it soon on this DAC.
Use TL431 as you LED. It''s like your LED but with three legs where you adjust the voltage. There is no TL431 tuned at 3.8V so it's just matter of adjust it.
It's the same but with better performance I believe. If nobody tried this it doesn't mean it's impossible. Just follow the rule.
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I / v stage dac end c2 & c6
I want to try some Russian PIO OTK for C2 & C6, what's the lowest voltage I can go with ? 160V should be fine ?
I want to try some Russian PIO OTK for C2 & C6, what's the lowest voltage I can go with ? 160V should be fine ?
how do you work that out? 160v is not fine.
Personally i never use a cap rated less that the B+ and then i add at least 10%. i;d look at 350v personally.
Personally i never use a cap rated less that the B+ and then i add at least 10%. i;d look at 350v personally.
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