Modding the DirectStream DAC MKI

Yes. simple.

Not for me.

Natures most forgiving instrument.

Only if one is not an audiophile. If this were the case none of us would be modding this equipment and be listening with earbuds and iphone to compressed MP3s.

Yes measurements are a good tool to assist in making decisions. But like statistics data should not be the only clue on how to solve a problem or how something can be improved. Look at the parts as a system and listen to them as a system as a basis. Or buy everything recommended at ASR.

Guess we are super human :grinning:

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Never said I was. I just followed most of Ted’s suggestions on how to address noise. He is pretty close to super human in digital domain.

Regarding listening and the ability to make judgement’s and distinguish sounds as what is natural. Ted uses the forum as a source of input.

Does anyone remember the name of the technician in Georgia doing the Edcor modification on DSD’s? I contacted him a long time ago and cannot find his information on my computer. Thanks in advance.

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Very interesting audio stuff going on in here- love it :slight_smile:

Some updates on the passive differential LPF output stage design for the DAC. The design is to a point that seems good so far to me. It has > -100dB rejection at 11MHz, along with excellent low freq response with proper size DC blocking output caps. . It has 75 ohms Zin at high freq. It has what I would call ~ exemplary step response and accuracy. All just in simulation so far, of course. Some screenshots below :slight_smile:

I’m quite excited to try it :slight_smile: Will build a proto soon using lower cost passives and start seeing how it performs in the real world. Assuming things proceed well, then will build with the best passives (most transparent, least obtrusive) I know of. I expect this could be quite good vs a transformer, but we shall have to see. I expect that it could lower the noise floor in the midbass/midrange; maybe dramatically. I expect that it should be incredibly transparent, using the passives and hand construction methods I have in mind. Again, we shall see. My high end audio bud is also excited. He also recently acquired a DS DAC (after hearing mine) so will have two pairs of ears on it soon.

Frequency response wideband- shows 20Hz and 10MHz values:

Zin @ 1MHz:

Vout step response with Vin 50% duty bit burst superimposed:

Vout step response ZOOM with Vin 50% duty bit burst superimposed:

Vout step response Vout only with Vin 50% duty bit burst:

Vout step response Vout only ZOOM with Vin 50% duty bit burst:

:+1:

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I think you mean Wayne @wctaudio. He did my transformers, did a great job for a very reasonable fee, and was a pleasure to deal with.

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Wayne @wctaudio. Did an amazing job installing my XS4400’s!

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I can recommend Wayne @wctaudio also! Top notch work fast turn around!

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I was too impatient to wait for the power controller board from @jkrichards, so I finally made a custom cable to hook my DSD straight to a Farad Super 3 (I don’t have a cover for where the Bridge 2 was so the wire runs straight out through there).

I used four runs of DH Labs OFH-20 (20awg silver coated copper) for each positive and negative, so eight runs of wire total. Hooked it up and powered it on, works like a charm! Immediately sounds blacker, yes a little more authority, but I’m waiting to see what the break in process will bring.

Question for the folks on this thread - has there been any comparison done between a fully modded DSD (upgraded Edcor transformers and LPS upgrade) against a Mola Mola Tambaqui? The last I saw was from 2020 on a stock DSD, and sunlight wasn’t out yet. Very curious about this if anyone had the opportunity to compare.

Sorry for the delay. I sent PM’s to members on the list with instructions to get the Power Supply Controller board.
Let me know if I missed anyone.
Thanks!

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PM me as I am missing info.
Thanks!

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List updated

Please add me to the paid list. Thanks

Done. Sorry for the delay. I wasn’t checking the forum that often as PMs show up in my email in-box. Didn’t know there was a PM limit.

Got the PM. Payment sent.
Toolbox149

Payment sent. Thanks Jeff.

It seems there is a limit per 24 hours. 25???

I can’t believe how difficult it is to get parts. I ordered USPS Priority Mail flat rate small boxes over a week ago and still do not have them. :dizzy_face: I really feel for the industry that relies on parts and materials to make a living. Thank goodness we sourced and received all the parts we needed for this power supply controller.

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