Updated: 02-Jan-06
Welcome to the DDDAC Column!


Happy NEW YEAR 2006 !!

2005, what happened?
Update on the 300B amplifier
GYDINEL, the story continues
(STILL :-) In the  pipeline....


2005, what happened?
First of all, this was a year of consolidation. At work, privately and with the audio hobby. This means for the reader of my Site, you have not been hearing much from me, but behind the screens I have been doing lots of stuff, but also tweaking things I will publish later on. Not typical quick tweaks, just small changes and then lots of listening... I also used 2005 to come up with the next version of the DDDA1543 MK2..... this was a major thing and I enjoyed the possibilities these days of small series SMD assembly and the access to very professional PCB making for small series and individuals like me.... I discovered the blessings of getting great I2S signals from a ripped CD, playing directly of a hard disk from the PC. All in all 2005 was a GOOD year !!! If 2006 would be the same I would be already a very happy man :-))) Join me in being so .....

Based on the many inputs I received from very happy builders and listeners, I started to put things in place. In the beginning I was kind of updating the old DAC, but as things moved on, I figured out, that a modular concept, leaving all freedom to do whatever one fits, I was doing the DIY a much better favor. As I worked my way through forums, I found more and more discussions on the fact that playing music from the PC over the USB interface was the next thing after sliced bread ......  So I expected many many designs for USB to I2S converts. WRONG !! Most designs on the WEB are doing the wrong thing, making SPDIF out of USB.... Read the results pages and you know what I mean.... What was left over were not very high end interpretations from the TI datasheet.... So I took the challenge and designed something what was actually very simple and straight forward, but seemingly no one took the effort for. The audible results are just great and I am working already on a Music server with a quiet PC and small touch screen :-)

Update on the 300B amplifier
I did a major work up on the KR 300BXLS amplifiers and was more than happy. This will follow soon, text is almost ready.... I replaced the old small Oil Filter Caps with  100uF BG WKZ ones. Also removed the Rk with the necessary decouple Oil C and implemented fixed bias voltage and the Tent Heater Supply. All this made the amplifier more dynamic, more direct, more transparent and for all dead quiet.... I great fit with the NOS DAC and SACD player with Transformer output. Some may like it to be to fresh and want the somewhat browner tube sound, but that might be personal. I prefer the sound as it is now, extremely transparent, without the "typical" analytical flat sound from a transistor amplifier....

GYDINEL, the story continues
The GYDINEL are coming to an end filter wise.... That took a long time, but mostly because it already sounded so good and I had so little time. Now I was suddenly and unexpected helped by Audio friend TriodeDick, who was suddenly geared up by doing some testing with a C79-C12 combination with active filtering for the low/mids..... We communicated a lot and Dick did many many tests, much more than I could ever find time. I followed his actions with some changes in my filter as well and the end conclusions are very interesting........ I hope to publish in spring or so. Want to give TriodeDick a far chance to publish first :-)) I hope he reads this, haha !!


(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 !! 
    January 2006 Note:  I made some redesigns, but give priority to the other projects.....need a long vacation I guess, grinsssss. 
  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 ....  
    This one is ready, but still playing on a "simple" power supply..... never the less, sounds great !!!!
  3. GYDINEL Hybrid Filtering
    I am currently building one large chassis, containing the passive serial filter (12dB Bessel...) for the C79-D20, the TUMOS with 250Hz 12dB filter for the C220 and 2 UD180 digital power amplifiers for the Subwoofers, which will be filtered by the Behringer unit.... 
  4. Krypton, 75 Watt Class A Push Pull Amplifier with 4x the KR 300BXLS
    I stopped this project, too costly, too bulky and the results for serial passive filter are so good, hard to convince my self I need to go through this.........


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