Audio Note Dac1.1x upgrade

[bambadoo]

Hi, I recently bought a "new" Audio Note Dac1.1 refurbished. It has the lateste boards. (The same as on the audionote webpages.
However it sounds a bit dull (lack of definition), and I know it has a big potensial.
I read on the audionote webpages that there are some changes between the different versions, and I like to know how to upgrade this dac to i.e. dac2.1x or prefereably dac3.1x. Of course I am aware that any waranty etc. will be destroyed once I open it, but that is my problem.
I can see that one of the differences is the "I/V Interface matching" which in version 1.1 has a "resistor over copper choke", and in version 2.1 has "Audio Note™ TRANS-410 copper wired mumetal core transformer" and in 3.1 "Audio Note™ TRANS-496 copper wired fully interleaved Supermumetal 250 cored transformer".
Is it possible to buy one of these and mount it on the analog board?
And how is the approach to this?
Of course some of the parts (resistors and capacitors and internal cablig) is changed also, but that is another story. I assume that is a direct replacement with better types (black gate, tantalum resistors)
I will email audionote regarding these issues.


Any other modification tips are also interesting.


Best Regards

[Elso Kwak]

Hi bambadoo, Please see this post:
http://db.audioasylum.com/cgi/m.pl?f...te&r=&session=
You can also replace the 74HC02 between the CS8412 and the AD1865 by a 74VHC02 or omitting the glue logic all together by installing my Asynchronous Reclocker. Schematic available by hitting the email button below this post.

[Cobra2]

AudioNote tube-DAC's, is IMHO very overrated, at-least the lower series.
And exept for output cap change, other "common" mods are just subtle tweaks.


Arne K

[bambadoo]

This is a version with AD1865n dac, and a cs8414.

In what sense will the 74VHC02 improve this dac?
Inside view of the dac:

[bambadoo]

Now this seems interesting. I took a picture of the analog board on my dac and compared it with the picture on audionotes page.
First the original from audionote


And lets compare it with the analog output on my dac:


A significant difference.
It seems that all of the an dacs have the analog stage from the first picture.

Regards

[ThorstenL]

Konnichiwa,

Originally posted by bambadoo
Now this seems interesting. I took a picture of the analog board on my dac and compared it with the picture on audionotes page.

The main visible differences apply to the absence of all the parts associated with the "de-emphasis" outputs. Some early CD's include a boost of high frequencies to redue noise/distortion. The switch, resistrs & capacitors missing on your PCB cover that. If you need those - I have used several DAC's without de-emphasis and have yet to come across a CD with pre-empahsis. The best known CD with pre-emphasis IIRC is Pink Floyd DSOM - I still stick to vinyl with this one.

As for the Transformers and filters, you should be able to purchase the higher grade parts from AN, but I suspect you would best off removing/bypassing the Filter alltogether, as this one of the main recent upgrades AN offers.

Better passive components and possibly better circuits for the Analogue stage etc are obviously also not a bad idea.

Sayonara

[audionline]

Hello,bambadoo,Do you have Audio Note Dac1.1 's schematic?Could you send me?
Thanks ,
E-mail:mc_wilson@21cn.com

[josiphal]

Bambadoo, try this link:
The Audio Note Kit 1.1 Tweaks Page

Josh

[bambadoo]

Hi, again. I have that link and it is interesting.
Regarding schematics. Sorry I don't have them.

Best Regards