R2R DA M1 Ultracap powered build

Oct 12, 2017 at 10:35 AM Post #181 of 229
Unless the load draws a constant current in which case the supply will perform perfectly anyway, you are not going to get pure DC out of something that doesn't have 0 output impedance. I don't think you know what DC means. A regulator will give purer DC then any amount of caps will unless you have crazy amounts of them in series/parallel to match the impedance and voltage upkeep capabilities of a decent regulator, not to mention the capacitive reactance of the capacitors will be an issue (or a benefit) if you don't parallel enough of them as well. Also you are not going to be able to hear microvolts worth of noise, the noise argument is silly.
It's not wise to spread unproven opinion as fact, especially when you continue to prove you lack an understanding of basic analog theory.
Okay now I'm out
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Oct 12, 2017 at 9:53 PM Post #185 of 229
Any news on demagnetizing Dibao's Balazs?
I find some demagnetizator(cheap one),just hope, this can help.I don't have any experience about dull sounding output transformers.Can trial tomorrow.
In my se monyo dac, I'm using 6.8uf solen pb series caps,(don't have 10uf)cant measure any dc. After caps,basic Toshiba j fet stages(sound good +0- 6v or up) powered u caps .I LIKE THIS SOUND !!!! (better than gd nfb 1 stage, the highs perfect also)

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Oct 13, 2017 at 4:38 AM Post #186 of 229
Looks great Balazs!

Those JCDQ210K buffer pcb with Toshiba 2SK246 / 2SJ103, C2240 / A970 are very inexpensive and do look great!
At my next shipment from China I will order some too for testing purposes.

You could use two of them to power left and right channel separately, or modify pcb to feed left and right channel separately.


I saw that TC-1 demagnetizing device on Taobao too, it is very cheap, around $8. Did you order one yet? Curious if it works!!!!
By the way, can you tell me what is the weight of this device? 1Kg or more? I ask because of shipment costs....

Keep up the good work!

Btw, I expect my ultracaps next week, DHL shipment is on its way to the Netherlands.....
 
Oct 13, 2017 at 4:48 AM Post #187 of 229
Balazs, if you are going to test this weekend, would you please try how da-m1 sound with output caps only, without jcdq stage behind them?

If I am correct, you wouldn't need jcqd, it only is better for impedance correction, but I think you don't need it. DA-M1 works best with
load higher than 10K, think your pre amp has 47K input impedance, so no need for impedance correction.

Could you please try? Output caps directly?

Thanks!!!

Alex
 
Oct 15, 2017 at 11:16 PM Post #188 of 229
Balazs, if you are going to test this weekend, would you please try how da-m1 sound with output caps only, without jcdq stage behind them?

If I am correct, you wouldn't need jcqd, it only is better for impedance correction, but I think you don't need it. DA-M1 works best with
load higher than 10K, think your pre amp has 47K input impedance, so no need for impedance correction.

Could you please try? Output caps directly?

Thanks!!!

Alex
just short trialed with demagnetized dibao.overall perfect,only the high not so good.today or tomorrow can trial only with caps.
 
Oct 16, 2017 at 1:02 PM Post #190 of 229
Thanks for sharing Tom!

Very nice to see ultracaps entering consumer market finally :)
There are already several reviews and user reports on the internet about the JR psu, all VERY positive

The psu looks very good, sadly it is just ONE psu with regulators behind the ucaps. Can you imagine how it sounds directly connected, without regulators? :)

We will keep going on with this :)

The amazement others are talking about when listening to the ucap powered preamp of JR, that just is what Balazs and I experiencing every time we listen to our ucaps powered DAC's :)

I had a defective cell (from the beginning) which resulted in a psu failure. I now am waiting for new ultracaps to arrive before I can go on with the project.


We had some difficulties with the output transformers which got magnetized cores because of DC-output from the DA-M1 modules. I asked Balazs to try demagnetize them,
it worked, but still not 100%. I concluded that DA-M1 can easily drive output directly, capacitor coupled, and the first tests of Balazs where amazing (tested today).

I will test too as soon as my parts from China have arrived. Probably will use Jentzen Superior-Z caps. Just have to try the lowest possible value to get zero DC-offset as a result.
The smaller the cap, the better the performance, and the lower the costs :)

Cheers!

Alex
 
Oct 16, 2017 at 10:08 PM Post #191 of 229
yes,only one cap between r2r modules and preamp.This is my best sounding config (at this time)
 
Oct 17, 2017 at 2:01 AM Post #192 of 229
So looking through this thread, what did you use to process the digital signal into analog?
I didn't find any specific post talking about the actual ladder R2R setup, or did I miss the post?
 
Oct 17, 2017 at 5:46 AM Post #193 of 229
yes,only one cap between r2r modules and preamp.This is my best sounding config (at this time)

You use 1x 6.8uF only at HOT output and not at COLD ?
 
Oct 17, 2017 at 5:55 AM Post #194 of 229
So looking through this thread, what did you use to process the digital signal into analog?
I didn't find any specific post talking about the actual ladder R2R setup, or did I miss the post?


Hi @Jimster480 ,

This thread is about the DA-M1 modules, powered with ultracaps, but to be honest, talk lately is only about the ultracaps or SQ in common.

We use DA-M1 modules which are the Audio-GD R2R modules that were available for DIY enthusiasts . These are not on sale on the the Audio-GD site anymore,
but you still can see the site and read about them: http://www.audio-gd.com/Pro/diy/DA01/DA01EN.htm

Kingwa from Audio-GD designed new modules (DA-7 and DA-8) which aren't available for the diy market,
the DA-M1 modules were the only ones who were available.

If you want to buy them, I can arrange it for you, in that case send me a pm.

Cheers :beerchug:
 
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Oct 17, 2017 at 11:52 AM Post #195 of 229
Hi @Jimster480 ,

This thread is about the DA-M1 modules, powered with ultracaps, but to be honest, talk lately is only about the ultracaps or SQ in common.

We use DA-M1 modules which are the Audio-GD R2R modules that were available for DIY enthusiasts . These are not on sale on the the Audio-GD site anymore,
but you still can see the site and read about them: http://www.audio-gd.com/Pro/diy/DA01/DA01EN.htm

Kingwa from Audio-GD designed new modules (DA-7 and DA-8) which aren't available for the diy market,
the DA-M1 modules were the only ones who were available.

If you want to buy them, I can arrange it for you, in that case send me a pm.

Cheers :beerchug:

Oh I see. I will do more research on this! Thanks a bunch
 

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