Modding DirectStream DAC MKII

Your post was deleted as argumentative and beating a dead horse.

I appreciate you are annoyed with the thread consolidation, but it is time to move on.

PM me if you need to comment further.


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We will be measuring the MK2 with the new nickel transformers Saturday. We already did a before sweep with the AP. Stay Tuned.


Out of curiosity, what are the differences between you transformers for MK1 and MK2?
If I understood correctly MK1 stock transformers have been secondary windings in parallel, while your transformers are already in series. MK2 both stock and yours have secondary windings in series. Does your transformers have different pin layouts for MK1 and MK2, are they different
voiced…? And what would happened if someone would install a MK1 transformer in a DS MK2?

They are not interchangeable.
If you tried it you would have no or distorted output.

Could you please elaborate on this?

I was under the impression that the Edcore XS4400 transformers were compatible with both the Mark 1 and the Mark 2.
If so, I would think that the basic transformer wiring requirements of either unit was pretty much the same.
I find it interesting that one of your transformers would not at least have a usable output in either model.

The XS4400 allows you to put any number of the four windings on the primary and have the rest on the secondary or even have multiple secondaries. The original transformer for the DS is prewired for a 1:1 primary to secondary, and to make the XS4400 work in the DS I duplicated this prewireing on the board so if a XS4400 was used it would work the same. The two transformers aren’t interchangeable in other configurations and in particular not in the Mk II configuration.


Thanks Ted.

What did you measure was equivalent output from the outputs regarding volume? I remember you reading you said that the difference was not just 6 in the volume when you measured it?

Basically we custom built these transformers for the exact needs for each DAC. These are not off the shelf transformers like the Edcor’s.
Wire size for both primary and secondary windings, how many turns and the core size and materials all effect the sound. It’s a balancing act to get them all right for the particular device and takes many hours and measurements as well as controlled listening test.

If your talking about the MK2 the output with the stock transformers is 3.76v at 100 volume. With ours it brings it up to the spec 4v at 97 volume.
If your talking about the MK1 the output is 3dB lower then the standard 4v with our transformers it’s +6dB louder and at 4v with the volume set to 94.

Hmm okay. I don’t have your transformers so couldn’t tell. I going back between my Jr and my MKii.

The Jr is set to 96, the MKii set to 90. Ted said the difference should be 6.

But, to my ears when set to 6, the Jr sounds a bit louder. I can’t tell why. maybe it’s the noise floor reduction on the MKii? But I’m almost preferring the Jr since it ‘feels’ a bit louder. Weird…

The Jr is a different animal.

What do you mean by ‘different animal’?

Not the same design. Also I can’t speak for what Ted said.

I should correct what I said a little. As jkrichards says the Mk II isn’t quite 4V (oops, we’ll fix that in April) so it is just a little quieter when 6 ticks down than the Jr. (The Jr is very close to the same level as the DS.)


Oh I see, I don’ have a meter readily available but should I make the difference perhaps 4 instead of 6 for testing purposes?

What happens in April?

That will be an easy fix for Ted. It has to do with the different transformers windings and the math in the FPGA.

The Mk II isn’t off by a whole unit. You can’t make the Mk II match the DS or the DS Jr only with the DAC’s volume controls. The UI update comes out in April; the UI is where the volume is trimmed in the DS series.


Ted - I really think you should blow people’s minds and make the output voltage selectable. Just think about the 1000’s of resultant posts.


Hmmm well 6 does a bit louder on the Jr compared to the MKii. I wish I had a multimeter to check the output and get them as close as possible.

Things that sounds louder usually sound better (more detail etc)