Final Round for the DDDAC1794-PBT

After celebrating the special 10-year anniversary of the DDDAC1794, it is now time to release the next version of this successful DIY-Project: the “DDDAC1794-MK3″. As always, there is “good news and bad news”. In particular for the loyal group of DDDAC1794 enthusiasts worldwide.

What is the “bad news”?
Unfortunately, there was no real way around it. As time moves on and boosted by the Covid pandemic we have seen an increase in demand for electronics components as well components getting short or even end of life. Some of the components used in the DDDAC are still uncertain in their availability (crazy long delivery times) or are just “end of life”. Enough reason to rethink how to keep the DDDAC available over a longer period of time to a broad audience.

What is the “good news”?
I have been working on the re-design of the DDDAC1794 for some time now. The goal was to maintain all the strong features and high quality of the current DDDAC1794 NOS DAC and apply new insights where possible. Squeezing even more sound quality out of it. The latter was a difficult task, given the superb quality of the current DAC. Prototypes have been built and been reviewed by me, Dick and Marco from Audio-Creative. They have extensively tested the prototype and provided some helpful inputs which will be applied in the final design.

A different design and approach for the new DDDAC
A good amount of user-feedback has been flown into the new set-up and design. For example, the PCB board is now a full-4-Layer design with power and ground planes. The PCB Layout is optimized for digital signals. Improved I2S buffering and regulation in the digital and analog circuit. Fitting (mechanically and electronically) to the new board I designed a new power supply, based on the well-known DDDAC power supply. The new design is equipped with active MOSFET rectifiers. More SMD components are embedded to make DIY construction an easier task. An option to connect an external Choke, creating a “CLC setup” is also provided. This option gives a significant sound improvement! More about the technical backgrounds and insights will be posted once the final batch is available.

But …
… the new boards/modules of the DDDAC1794 will no longer be mechanically compatible with the current DDDAC (Mainboard with stacked modules). The new design will be mechanically different. What of course remains is the use of the PCM1794 processors. I wouldn’t know of a better one which sounds so good. If implemented correctly…

… due to the wide offering of SPDIF to I2S converters, the SPDIF function on the new DDDAC is no longer available. It “only” has universal I2S input.

The new version …
… will consist only out of one PCB board containing the mainboard functionality and 4 PCM1794 chips (which is the equivalent of 2 decks in the current version) It can be pre-set for mono (being a Left or Right channel) or stereo use. One PCB board will be a full DDDAC equivalent to the old Mainboard+2 DAC-Modules. Two boards on top of each other will give the possibility for a double mono L+R setup with the equivalent of a 4 decks DDDAC-PBT. Interfacing is made easier with added U/FL connectors. Current consumption is halved and more niceties …. The valued concept of upgrading by parallelizing multiple DAC sections stays the same as before. Even here more than 2 boards parallel will be possible by connecting outputs together.

What exactly will it be and what will it look like? I will post and elaborate deeply on this when the new DDDAC1794 is back from production and ready for sale.

Still some good news:

Have you been considering an upgrade of DAC boards for your current DDDAC1794? Or still buy a set of the current version? Now is the time to make decisions! There are some main and DAC boards left in the Audio Creative web shop. But gone is gone!

In case the current stock is sold out, or you are too late, no worries, there is a very last chance…

Last time buy (“Group Buy”)

I will run a last production batch of the DAC-Boards (not the main boards) for those who still want to upgrade their current DAC with more decks. Or want/need spares…
But only if we achieve minimum goals and parts availability. These are the “Rules”:

• I need a minimum of ~ 50 boards and availability of the parts.
• You need to subscribe in the Response Form – See below Form.
• If you subscribe it is a binding commitment as soon as the last time buy is confirmed (enough boards and parts)
• Last date for subscription is December 10th.
• If minimum level is achieved and components are available, I will confirm, and subscribers will be able and invited to enter a purchase order at the Audio Creative Website. You also WILL have to make the payment at that time!
• The Special Web Shop order option for the last time buy boards will stay open till December 20th to avoid dragging this on and on.
• If all orders are in and paid for, components will be purchased, and boards will go into production.
• Expected start of delivery is end of February / beginning March.
• No returns possible

If you somehow appreciate my work and time I have put into all this, feel free to make a (small) donation:
Would be very much appreciated 🙂