Updated: 14-Dez-04
Welcome to the DDDAC Column!


Long time no see .....

2004, what happened?
(STILL :-) In the  pipeline


2004, what happened?
I admit, 2004 was not directly the year with the regular updates I promised my self to do.  Not fair to the regular visitor, but time was somewhat constraint this year. Never the less, my Site is visited very frequently and for that loyalty  I need to thank the readers, that even when updates are not showing up, there still seems to be enough to read and check back for :-) Just for statistics... In 2004, so far, I had like 700.000 Page hits and 85.000 visitors. 35 GByte was transferred .... For this it is I spend time creating this Site and looking at the reactions I get almost daily per email, I for sure will continue..... And I hope your patience will be rewarded, when I find time so now and than to update the Site :-)

If I need to give a "reward of the year" to my self for the project, which was most popular, it is by large the small, very good sounding DAC with the 8 TDA1543 chips and reclocking.... The DDDAC1543... Many readers actually built this version and I have received many positive reactions. Most of them with the same kind of message: Very good, much better than a standard (even expensive) CD player, better than most commercial or oversampling DAC's and only very occasional, beaten by another DIY concept, based on the TDA1541 or PCM63P. But it always ends with statements like: "BUT, the other DAC is more then 10-fold in price and complexity" Which makes it the absolute winner in price / performance and a project which can be completed by inexperienced beginners....

This is a kind of in between project, trying to create an alternative way of listening to music to my audio equipment. An electrostatic Headphone from Stax, driven by a directly coupled Tube amplifier. No Transformer, no capacitors. It was not intended as over the top high end design, but the audible quality is astonishing.... Specially the fact that the whole audio range from deepest bass till finest high is coming to you as really one homogeneous sound is an experience you will not make with normal loudspeakers.... This project is not so easy to built may be, but for those who dare and have some experience, this good be an interesting next project ! 

Talking about loudspeakers..... I have been working in the back ground at the Gydinel Filters and did some interesting discoveries. First of all, that the Mundorf Silver Oil Capacitors are extremely good, a class better than the also excellent sounding Auricaps. So good, I bought a whole bag of 470nF and 100nF to slowly start replacing the couple capacitors in my amplifiers... Another experiment was done with a Digital Filter from Behringer, the DCX2496. This piece of equipment allows you to drive every speaker unit individually and set by the PC the filter characteristics, like filter type (Bessel, Butherworth etc) slope (6dB-48dB) and much more. I will update the Site later at the Gydinel pages when I (finally) have made the modifications in real life on the Gydinels which came out with the simulations. As a big jump forward, we found out by listening only, that 12dB Bessel filters were optimum for focus, stereo imaging and neutrality.... Which I found refreshing, after all those years I hung a bit on the "religion" that only 6dB could be good...... May be later you read about this :-)

I actually did a report in a Dutch forum, so if you can read Dutch, you could peek ahead :-) The actual report of the listening session is on page 4


(STILL :-) In the  pipeline....
What a luxury problems I have !! Still a lot of projects in the fridge or are "half way" from its final stage.....
Just peek in my design kitchen to keep your appetite in visiting my Site......

  1. Laboratory Power Supply (all you need to test tube and other equipment):
    Regulated outputs: 0-500V 200mA, 0 - NEG100V (negative grid) 0-25V  1A   (2x), 0-100mA  current  source, 100mA  - 1A current source
    AC outputs: many, many, all you need to feed filaments from any possible tube....
    LCD Voltage meter
    LCD  Current  meter
    December 2004 Note:  I WAS ready, but I smoked the power output stage...... Now I need to repair and make some redesign to make it idiot (that's me :-) PROOF !! 
  2. New Line  amplifier, modular setup
    Basically the existing DD PRE, but with 3 chassis, Power supply, RIAA amp  and line amp. As you can read, the PhonoDude Hard Wired version is ready now. The Line amp will use the Siemens SIF Ba Tube and Battery Filament supply. The amplifier Chassis is ready, "only"  need to build the Power Supply ....  
  3. Gydinel Active Filtering
    Need to finish a concept of active loudspeakers filters with help of the TUMOS and ZAP Pulse amplifiers  (yes, I built a pair of ZAP's ... but that is hardly a real project :-) Also missing is an extra Tube amplifier to drive the midrange ------ > 
  4. Krypton, 75 Watt Class A Push Pull Amplifier with 4x the KR 300BXLS
    This is my greatest challenge at the moment. I have most of the parts in house, but largely struggling with the chassis set up. It is impossible to put everything on one chassis... So I need to find a clever concept of splitting the power supplies and the amplifier part.... I am not in a hurry, but sometime I need to get started :-)  Any inputs are welcome !!!


Happy Listening and Building !!!!

Doede Douma


IMPORTANT: The information provided on this page is intended as guide for DIY activities and therefore free to copy and or publish. If any one wishes to use any of the information from my WEB site, please make sure to refer and footnote to my URL Link as source! Doede Douma