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Reference DAC Module - Discrete R-2R Sign Magnitude 24 bit 384 KHz

PKI

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Joined 2011
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That's Dimdim's mod for earlier revs. If you have rev.3+ there should be vias in the middle of the board which would make things easier. If you haven't made the purchase, consider dam1121 1921/1941 ;)

Btw, I have 3*1500uF UCC caps per rail (don't get UCC though you'd have to trim/thin 48 leads by hand...) and if only you can hear the dynamics right now... I don't know enough about opera but Pavarotti has never sounded better. Pretty much perfect. And I'm never biased.



These?
IMG_0212.jpg

Would you mind sharing a link for those 0.68mm leads Nichicon?

I already have the dac. So yuh are saying 19x1 doesn’t require any mods to add more caps?
 
These?
View attachment 730511

Would you mind sharing a link for those 0.68mm leads Nichicon?

I already have the dac. So yuh are saying 19x1 doesn’t require any mods to add more caps?

Easy questions first... PLG0J182MDO1 Nichicon | Capacitors | DigiKey Double check the lead diameters before purchase... Buy this only if you can't source really cheap 1500uF capacitors. I got 30 1500uF UCC caps that measured +4~7% its rated capacitance and good ESR for much less than $10. Not from Digikey though.



Seriously? Do you think you can perfect your DAC in a way the imperfections present in the soundfile go away? You can only control the final piece in a very long chain.

So again, on the recording / mixing / mastering side of things there were ADC and DACs involved with significantly less processing power and a need for realtime performance, so you can bet their filters don't use a million taps. Yet many suceed in sounding great. Not all of them, but for more reasons than the filters....

I've got 12 bit studio samplers from the 80s that sound really nice... It can surely be done in an FPGA in real time.


Is it true that a larger error will always mask a smaller error? And is it really something to argue against when correcting for the smaller error costs very little?... Now whether the result is audible, that's a much longer answer.

I have no idea what's causing the harshness in the dac. No idea at all. I was just trying filters....
 
Easy questions first... PLG0J182MDO1 Nichicon | Capacitors | DigiKey Double check the lead diameters before purchase... Buy this only if you can't source really cheap 1500uF capacitors. I got 30 1500uF UCC caps that measured +4~7% its rated capacitance and good ESR for much less than $10. Not from Digikey though.

Yes, the part you showed has 0.6mm leads. Lead spacing is 5 mm. Does that fit the holes of rev4&5?

Would this FC cap work for vref as well?
Panasonic EEU-FC0J152 Elektrolytische condensator Radiaal bedraad 5 mm 1500 mF 6.3 V 20 % (O) 10 mm 1 stuks | Conrad.nl

Fedde
 
How do you do the caps mod for the 1121? I don't see any vias on that board...

Thought I should still chime in on this...

Ask TNT or Jogi... I think you might just have to parallel it on the ceramics. My honest opinion is that before I did the vref mod, the bass sounded very thin compared to my (!) laptop output. It was punchy, but something was wrong. Now it's all proper. Of course the dam1021 is more real sounding and detailed in the bass, still punchy with the 1.19 linear filter - which was what I had before the vref mod too.

I would also consider the vref caps as part of Soren's design, though he would obviously deny that. 1941 has 800uF+1000uF per rail at least. 1541 has 1000uF. Note that this "technical reason", which is totally valid by the way (check the measurements posted earlier or on hifidruino), will skew your perception before and after the vref mod since you can't do ABX. I don't think my strong recommendations above need to be qualified, however. This is advice from my failed experience playing with the filters. Anyways, something interesting to think about and keep in mind :)
 

TNT

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Joined 2003
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Once i get to work on one of these i plan to remove all ceramics, replace them with ecpu and probably leave a couple of empty pads for adding electrolytics.

I don't believe that is technically sound (intended!!) These are for HF decoupling - your replacement will not do that job on those frequencies. Don't forget to do before and after measurements - also on the outputs!

//
 

TNT

Member
Joined 2003
Paid Member
Yes I felt so in the sense that I got the feeling of listening to the master "tape" with the 1121. But my 1021 is not tricked out - I did the low res mod / 1800uF if my memory serves me right - I don't have the unit here. I maintain 2 system in different location - quite different but I enjoy them both really. When I'm at one, I long for the other - and vv.

//
 
Member
Joined 2008
Paid Member
Yes I felt so in the sense that I got the feeling of listening to the master "tape" with the 1121. But my 1021 is not tricked out - I did the low res mod / 1800uF if my memory serves me right - I don't have the unit here. I maintain 2 system in different location - quite different but I enjoy them both really. When I'm at one, I long for the other - and vv.

//

ok. that's helpful. thanks.
 
If the 1121 is better than the 1021 why wouldn't people just buy it instead?

Because:
(1) Soren claims they're the same, only 1021 is better for DIY. On the latter point I agree with him, it's much easier to ruin 1121 since the board is thinner and generally more miniaturized/fragile. But to claim that the technically superior 1121 sounds the same? Well ABX is almost a must perhaps. You can be the judge of that...
(2) 1021 is cheaper
(3) 1021 came out much earlier and as such has a much much larger user base and support community

(4) 1121 needs separate power supplies which is great but might discourage some people

(5) 1021 has onboard buffered outputs. To be honest now that I think about it, 1021 is the best choice for me since I use headphones. I don't think the onboard opamps will distort the sound that audibly. Maybe it lacks the sweet colorations of "hi-end" amps. But I'm not sure if I should care. So I don't care. 1021 is basically an all-in-one solution for me.