Did you already somewhere describe the differences to the 47uF and why you used a different value?
We did not include the 3rd order filter / opamp circuits. The AP test signal was fed onto the transformer. If we did include the filter our measurements would be useless.
With the C704 installed you have a 5th order filter.
Others have discussed this many times.
I like them as they are easy to install.
Also they will make a total of 880uf per channel.
Found it and got that those were the bigger green ones. Didnât recognize so far that they were not only different to install but also different values. In a post you described yourself that you didnât hear a difference between the values and just used them because they are less sensible to install and donât short when failing as the tantals.
Iâm only starting the fact that with these tants and the nickel transformers with a USB shorting plug is the best I have ever heard so far. No other mods.
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Yes, seems to overrule especially the ext. PSU effect.
I just didnât know what difference your different R6 caps in the one DAC made, so I was curious.
For me also the three biggest changes of these mods are VOCM, Lundahls and the now proper top end extensionâŚdonât remember the PSU effect in detail anymore, but I think it was a little less essential, still important.
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Yes VOCM mod and a transformer designed specifically for this DAC is unbeatable.
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When I switch from 15 to 6.8, the problem that I complained about before coming from the speaker was solved.
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Yes. 15 is too aggressive with the LL1948 transformers.
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To be honest, the lower value solves a characteristic I perceived through the original Mk I, through the XS4400 update and the LL1948 with 15nF⌠not just with the latter.
It delivers a completely new quality in cymbal, string tones, openness. I just may go back a little as the 6.8 seems a bit over the top in my case of this confirms after burn in.
For those with sensible setups it may be important to know, that the improved, more controlled bass together with this more open top end leads to a partly less rich and mellow but more resolving character of the DAC. Maybe a bit similar to what some experienced with the Mk II as I understood from postsâŚ
And due to the VOCM bass changes itâs necessary to readjust subwoofer phase and redo sub EQ when previously verified by measurements.
To power the AD1839, we need three things: a separate 30W transformer with two windings 15V 0.8-1A, a 11V rectifier / stabilizer and a second 7V regulator. This stabilizer is installed directly on the analog board, solder the output leg to a large area of the previously removed Q700 transistor.
It is important to note that the minus that we lead from the first LT3042 stabilizer to the second is soldered first to the ground leg of the C700 capacitor and only then to the minus of the stabilizer.
The second point, on the first stabilizer LT3042 there is a resistor, the value of which sets the output voltage, in our case 10 - 11V. This resistor is very noticeable in the sound!
I use R-Cor type transformers, they sound better than a torus in an analog path.
Here are links to the components I used:
- Low Noise LT3042 Linear Regulator Power Supply Board DC Converter Overvoltage | eBay
- NewClassD UWB2 LC7807
P.S. And yet, if you use Wima on the C704, then keep in mind that it has a direction. Place it with an inscription from the transformer.
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We also did the external power supply and RF shielding along with a SR Purple fuse on our DS2 with the new Nickel transformers. It did improve the sound quality a bit however not nearly as much as the VOCM and Transformers. I think we now have it sounding the best possible until we do the AD1839 opamp update. DC offset and distortion is our enemy here with the AD1832âs.
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Evidently canât wait to operate on DS MK 2? Understandable youâre exiciitement.
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Yes. You got that right 
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Wait. Iâm confused. Is the bolded reference above with respect to a DS MkI? But the big question is - with whatever mods you did to the MkII, how does it sound next to this recently modded MkI? Although if this MkII doesnât have several hundred hours on it, any comparisons should be taken with a grain of salt.
I think the mods on the mkII shouldâve been done after the unit was fully broken-in. Easier to tell whatâs going on with the upgrades after everything was fully settled in.
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I donât think any mods have been done on a Mk II, except possibly for an output transformer switch. Things like Vocm and external power supply donât make sense on the Mk II (without a lot of questions anyway.)
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He doesnât have a Mk II yet heâs talking about one of his Mk I samples.
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