Soekris Dam Dac

[jkeny]

anything ive tested with a regulator post batteries caused a sq bottleneck, cant see how supercaps would be any different
so basically what this guy built is a uptone supercap ps clone?

which its implementation makes little sense to me

i would have thought a supercap ps best chance of good sq
is constant charging from low noise reg with no regulation post capacitors

Yep, the pre-regulation of supercaps (or batteries) is what most don't want to contemplate - it seems counter-intuitive
When I first discovered this approach (about 8 years ago - it was such a simple idea, I wondered why no one had tried it before?), I knew it was superior to anything else I had tried - just shows what experimentation, unshackled by pre-conceived notions of what works & what doesn't, can reveal!

[abraxalito]

Ah, I see on that thread that Abarteis is fired up with conviction & not understanding Nige's & Markw4's posts

He does look exceptionally autocratic on that thread with his stipulations.

I wonder about CM noise when batteries or ultracaps are being concurrently powered while driving circuit? In my experience this configuration seems to eliminate CM noise but I'm not sure of the mechanism by which it is doing this. I guess it's a case of seeing the system wide picture of the current flows & how this is changed by inserting a huge capacitor (or battery) into the mix?

I can't see how using caps or batteries can eliminate CM noise in that situation. Perhaps just the setup does not generate much CM noise or the effects are being somehow masked? What amp is in use? Normally its the susceptibility of the amp to CM noise that's the weak spot, at least IME. If your amp doesn't have a mains earth connection (so that its class II, 'double insulated' for example) then that will make a difference.

[jkeny]

I wonder about CM noise when batteries or ultracaps are being concurrently powered while driving circuit? In my experience this configuration seems to eliminate CM noise but I'm not sure of the mechanism by which it is doing this. I guess it's a case of seeing the system wide picture of the current flows & how this is changed by inserting a huge capacitor (or battery) into the mix?

I can't see how using caps or batteries can eliminate CM noise in that situation. Perhaps just the setup does not generate much CM noise or the effects are being somehow masked? What amp is in use? Normally its the susceptibility of the amp to CM noise that's the weak spot, at least IME. If your amp doesn't have a mains earth connection (so that its class II, 'double insulated' for example) then that will make a difference.

Yes, thanks, I wasn't sure how CM noise could be ameliorated by this & I haven't measured CM noise & it's reduction. I assumed from my experience with all the installations of my battery powered devices in the field, that CM noise was being addressed in some way & that was at the heart of what was happening but maybe it isn't?
It seems from descriptions of the sonic improvements reported with CM noise reductions that I have read, they are pretty much the same as the sonic improvements reported with my devices?
Maybe it's not a reduction in CM noise but rather a reduction in it's effect that is at play but again I'm not sure what mechanism could explain this?

[nige2000]

ive float charged the cells in amps dacs computers etc with 'decent' linear supplies
none are directly earth gnded
there is no subjective difference in the sound listening as its been charged or not
however i do remember noticing a small degradation using poorer smps supplies

computers seemed to benefit the most from lifepo4 supplies,
i assume switching noise is the bulk of the problem here?

weirdly i see my last post was deleted at diyaudio
mod said i was not at fault was just a clean up
didnt think it was doing any harm

dont think ill get the answers from him anytime soon anyway

[jkeny]

ive float charged the cells in amps dacs computers etc with 'decent' linear supplies
none are directly earth gnded
there is no subjective difference in the sound listening as its been charged or not
however i do remember noticing a small degradation using poorer smps supplies

I've used grounded linear supplies & not noticed any degradation even when charging with SMPS.

computers seemed to benefit the most from lifepo4 supplies,
i assume switching noise is the bulk of the problem here?

Yes, the stability of the battery PS may show it's superiority in this scenario

weirdly i see my last post was deleted at diyaudio
mod said i was not at fault was just a clean up
didnt think it was doing any harm

dont think ill get the answers from him anytime soon anyway

Don't think he has any answers to get!

[jkeny]

IanCanada on that DIYAudio thread seems to like the Ultracaps. From memory he has favoured LiFePO4 batteries in the past so maybe his will be the best comparison of one Vs another? I presume he is using Vregs on Ultracaps output so I can't see how they could sound better than LiFePO4 without caps?

[abraxalito]

IanCanada on that DIYAudio thread seems to like the Ultracaps. From memory he has favoured LiFePO4 batteries in the past so maybe his will be the best comparison of one Vs another? I presume he is using Vregs on Ultracaps output so I can't see how they could sound better than LiFePO4 without caps?

From my reading of his posts he's avoiding using Vregs and the reason he's given makes sense to me - its because of feedback. This harks back to peufeu's thinking that the way to test a reg is to put a signal on its output and see how much distortion gets generated. I'd go a step further and put noise on the reg and see how much noise it puts out in response. We could try this test with batteries and ultracaps, my guess is they'd put out nothing.

[jkeny]

IanCanada on that DIYAudio thread seems to like the Ultracaps. From memory he has favoured LiFePO4 batteries in the past so maybe his will be the best comparison of one Vs another? I presume he is using Vregs on Ultracaps output so I can't see how they could sound better than LiFePO4 without caps?

From my reading of his posts he's avoiding using Vregs and the reason he's given makes sense to me - its because of feedback. This harks back to peufeu's thinking that the way to test a reg is to put a signal on its output and see how much distortion gets generated. I'd go a step further and put noise on the reg and see how much noise it puts out in response. We could try this test with batteries and ultracaps, my guess is they'd put out nothing.

Ah, right, I didn't read closely enough - I presume then that he is putting two ultracaps in series & putting some balancing circuitry between them while feeding them 3.3V which is then used to power directly 3.3V to ESS DAC?

[bogdandascalu87]

Hello everyone,
I want to make the 1.2 and 3.3 ldo upgrade on my dam1121. If i remove the stock regulators, it is correct to tap at the marked points to supply the board with 1.2 and 3.3v? After the mod, do i still must supply 5v vcc5d at pin 1 and pin 2 of thej2 header? U47 seems to be impplied in the muting circuitry(maybe) and is connected to pin 1 vcc5d. Are there anyother parts supplyed with 5v?

Best regards,
Bogdan

Ps: More is written about the 1021, but poor or none regarding 1121. Maybe with our sustained effort we can do a little more documentation about this little board.(eg clock upgrade, output capacitor, vref transistor mod, etc)

[Bmxmen]

Hi my name is Kamil. I have an question about baterry power supply.
If we get on referency 4v .3.3vbatery we get full 1.4v rms out Still?
And why Nigel use 2cels on ladder not 4cell. Each for one shifts?thank you very much