Now it’s time to try the Duelund CAST Ag (CAST Silver) on my Aikido Preamp. You might be interested to read the installation process.

Short words, here is the final installation photo. For the break-in purpose, I don’t use expensive configuration. Usually the main source is my old iPod Photo, connected with old hi-fi amplifier, then my DIY speaker. Few hours break-in session should be enough for initial impression. Although serious listening evaluation must be done at least after 100 hours of break-in period.

Some brief information of my Aikido Preamp, if you are not yet familiar with it:

  • DIY Main Transformer, Z11 core/38 size with Germany/Australia copper wire (330V-CT-330V/100mA, 0-4-5V /5A, 3.2V-CT-3.2V/5A, 0-90V/50mA)
  • Russian 5U4, 5U4G-B, or RGN 1054 Rectifier (available via Octal->B4 DIY converter)
  • Choke Input with 3 Chokes total, no Resistor in Power Supply line, except Bleeder Resistor (TKD)
  • Jensen 4-pole, ASC, and VCap TFTF Capacitor in Power Supply
  • 6N1P and 6N6P tubes
  • Russian K40 as filament AC Bypass Capacitor
  • DACT 100K Stepped Attenuator
  • Jensen Copper Foil Aluminium Tube as High Voltage Bypass Capacitor (inside PCB)
  • Kiwame, Riken, Shinkoh, and Vishay S102 Resistor in critical position and Vishay L6C on “not really important” position
  • Duelund CAST Ag (CAST Silver) as coupling capacitor


Power it up, let’s check the voltages! This is important to make sure all the parts will get sufficient and correct voltage. All measurement below are taken on loaded condition with my Sanwa PC510 TrueRMS multimeter.

The main rectifier is supplied with 321VAC-CT-321VAC or 642VAC end-to-end. This is measured in loaded condition. The unloaded will produce 333VAC-CT-333VAC or about 666VAC. It seems that the main transformer is very good in production and could produce very stable and less noise.


After rectified with 5U4 and Choke Input, we can get a clean 222.4 VDC. As you can see, the 320VAC input (640VAC end-to-end), could produce only 222 clean DC out. I wonder how not efficient this one! I lose almost 100 V! “Thanks” to the Choke Input topology 😉


The rectifier filament voltage measured around 5.1 VAC. Good!


The 6N1P and 6N6P filament measured at perfectly fit 6.3 VAC. Another excellent job!!!


After all test have been done perfectly, I started to play some music. Some equipments involved were Kimber MST-Cu Interconnect, Synergistic Research “custom” Speaker Cable, DIY “confidential” Solid State Amplifier, and my DIY Speaker. As source, I consider my “modded” iPod Photo should be enough for pre-break-in session. All materials were WAV and ripped from the original CD.

At first opening, I started with Ingram Washington with “What A Different A Day Makes”. I got a very solid baritone vocal of Ingram. The microdetails of the brass/cymbal definitely far beyond the CAST Cu. I almost couldn’t believe myself. I have been here for long time, listening the same music for months and years, but the cymbal and brass of the Ingram never heard so damned good! If before with CAST Cu, the cymbal and brass pronounced very well and natural, now with CAST Ag, you could heard even more. It’s seemed not just the tone itself played, but it was dancing all over you (more harmonically rich). Seemed ridiculous and hard to believe… All the other instruments played in a very solid, clear, and perfectly “in-line” and controlled.

Next, we continued with John Campbell on Howlin’ Mercy album, the “Down In The Hole” (also available from Dali Reference CD I). The guitar and some unique instruments sounded very real, natural, and really “dancing” on every tone played. I’ve been listening this album in many system so I knew most of the tones very well. The voice of John also produced with very good depth, just like he was singing really “down in the hole”. No surprise many people loves this track.

Next, I use short track from Amanda McBroom on Growing Up In Hollywood Town album, the “Love Letter” track. I love the piano and saxophone on this one. The sound stage was wide and depth. I must confirm if this one was wider than my previous CAST Cu and another thing was a better separation. Getting in the middle of the track, the music was getting more complex and crowded, but it seemed never crowded enough to trouble the CAST Ag. Enjoying this album even more, I went to “Peter The Hermit”. I could also confirm that this CAST Ag also very fast, even if your music was getting more complex, there was no sign that CAST Ag was running out of breathe. The low region also controlled very well, tight and short bass.

After quite satisfied with male vocal, I switched to Norah Jones with “Come Away With Me”. I have to admit this was not a very good recording, some distortion could be heard if you have a sharper ears. But overall, most people love the seductive vocal of Norah, included me. There was no doubt, the CAST Ag could produce a nice combination here. The guitar sounded so delicate. An extra note from me, the vocal although sexy and seductive, it seemed still not clear enough yet, like covered with a transparent fabrics. I could understand that most Capacitors – Duelund not excluded – would face this issue before passing the break-in period. I didn’t really “care” about this on previous male vocal testing, but quite noticeable on female. Note: after another 5 hours and repeat the same test, it was getting more and more transparent.

We continued with Chen Lily – LPCD45 album, Track #5 (我和你). I always love Chen Lily sweet vocal. Although most of her album sounded a little bit “digital” and “artificial”, but the sound engineer could do the job perfectly to create an enjoyable album. The CAST Ag maintained the very good sound staging (or even better) and the sweetness of vocal. To be honest, I was a little bit pessimistic to try anything with Silver related material (first, it’s expensive – second, usually it tended to emphasize the mid-high tone), but luckily, this CAST Ag didn’t have such characteristic.

Finally, I played Patricia Barber with “Black Magic Woman” from Companion album. Wow, the speed was amazingly fast, detail, and very well controlled. If you are familiar with this track, you should know that there are so many complex parts inside this track. If your system doesn’t have enough capability to produce this complexity, then prepare for a headache, especially caused by the traditional high pitch instrument. The mids of this CAST Ag also well tested on this track and perfectly done.


Finally, I changed the rectifier with RGN 1054. The DC voltage produced downed to about 216 VDC. The sound, especially on the vocal, became more delicate, more transparent, and also add some resolution there.

Remember, this is still a preliminary testing. Complete and fair judgement should be done after next 150-200 hours. So, we have a long time to go. It’s also interesting to do a fair A-B match between CAST Cu and CAST Ag.

Now it’s time to sleep… 😉