Just what I’ve promised before, finally today I do the most awaited Capacitors Battle. Actually the “real battle” will be done within next few days. Let’s say, this is as first impression to “hear” how good they would sound 😉

I use ELMA Switch (2 poles, 6 positions). Click here for details. The connection in details also explained there.

Here is the appearance of my jig. It’s an Aikido Pre-Amplifier. Powered with 6N1P tube in front connected to 6N6P tube as buffer stage. Rectifier is RGN 1054. The capacitor used as output coupling. Each channel has it’s own ELMA Switch. Please remember the selection is made in “perfect” mode (read here for details). Oh, I use empty CD holder as base for my ELMA 😉


Here is the ELMA Switch. Each capacitor connected to 1st and 2nd pole of the ELMA. This will create a perfect connect/disconnect circuit for every capacitor tested on every switch position.

The contenders are (sorted by the price that I paid around  June 2009):

  • Jensen Copper Foil 0.47uF/630VDC price around US$ 36.95/each (US$ 73.9/pairs)
  • Jensen Copper Foil Paper Tube 0.47uF/630VDC price around US$ 86.95/each (US$ 173.9/pairs)
  • Mundorf Silver/Gold/Oil1uF/1200VDC/800VAC price around US$ 88.60/each (US$ 177.2/pairs)
  • VCap TFTF0.47uF/600VDC price around US$ 139.99/each (US$ 279.98/pairs)
  • Duelund VSFCu-PIO/CAST –  1uF/630VDC/300VAC price around US$411/each (US$ 822/pairs)


Another shoot of the capacitors. They are stuck behind the small ELMA Switch. Sorry man, no extra place or extra cables allowed, to minimize any extra coloration.


The selector outlook from the front. I use CD holder plastic to put the ELMA right on the center (yes, it does have hole on the center, perfectly fit with my ELMA). Now I can switch the capacitor in real time (not really real time, since I need to mute the amplifier to prevent any “thump” sound).


Almost all the equipment used are DIY and affordable in terms of price. The source are CEC CDP, a DVD Player (fully modded), and a Wadia iPod docking station. The amplifiers are MOSFET  (yes, we used more than 1 amplifier). Some are  running in A-Class, and some in heavy AB-Class. The speakers are 3-way, floor-stander. Sorry, I don’t put the image since it’s not really important on this “first impression battle”. And most of them already post frequently on this blog.

How’s the result? 😉 All the capacitors have passed 200+ hours break-in time.

FYI, this is just initial impression. More result and/or revision will be posted soon.


First, we try the “classic” Jensen Copper Foil (metal yellow can). This is one of my favorite (before). It has good vocal, but the high is fine (not dull). But this time, this capacitor sounds a little bit too “crowded” for me. It’s not bad for US$ 73.9/pairs and it will fit for most of your tube application. But this time, the capacitor is not on the level to compete with others.

Then we move to Mundorf Silver/Gold/Oil. This is also one of my favorite (still). When you always remember a dull sound from an oil capacitor, then with addition of Silver and Gold material, the Mundorf S/G/O simply will change your imagination about an oil capacitor before. It has sharp, straight sound, and good staging and layering. I almost can’t believe that this is still an oil capacitor! If you want to add some high tone extension of your current setup, then this capacitor is for you. If you want to add some sweet in the vocal, then you have to pick another one. I believe this will fit for a “shy” soft dome tweeter. With its expensive price tag, US$ 177.2/pairs, you gotta make sure this caps is matched with your system.

We are moving to a more serious one, a VCap Teflon TFTF capacitor. Some claim this is as a best signal capacitor. Well no surprise here, the price tag is US$ 279.98/pairs! You gotta be kidding to say this is just another capacitor. This is the only Teflon based capacitor on this round up. How does it sound? Details details and more details, that’s all I can say. It will translate every note perfectly with the details. Is that what I call transparent? Definitely! But somehow, I experience a cool sounding system. Am I too tubey? I think so. If you expect a revealing capacitor and could match is with a “too warm sounding system”, then the winner is yours!

I keep the last two for Jensen Copper Foil Paper Tube and Duelund. Why? First, they “share” a “similar” sonic. Why do I use quotation mark? 😉 Because they are similar also in terms of the appearance. The brown paper made tube.  Hmm… this Jensen reminds me of… Duelund. Well, I don’t want to speculate whether they are the same or not. Let the ears decide!

Jensen Copper Foil Paper Tube has excellent vocal. The musicality is there, defined perfectly. For its “cheap” price tag (US$ 173.9/pairs), it’s simply a clear winner here. It’s not as revealing as VCap or as “sharp” as Mundorf S/G/O, but the overall tonal balance is fine. Some weakness may be seen when playing extra detailed instruments. You will soon remember the old Jensen Copper Foil capacitor. The high is not dull, but not as revealing as VCap. That’s it.

Now it’s time for the Duelund CAST PIO. With a massive US$ 822/pairs price tag (+2 months waiting time), I expect a perfect one. And Duelund gives that to me, perfectly. If I complain about Jensen Copper Foil Paper Tube weakness in the extra detailed instruments, then Duelund really fixes that problem. The high is very clear, transparent, and well defined – but never heard aggresive. If you have VCap, yes it has superb Teflon detail, but you also will notice somehow it has “cold” sound. This will never happen with Duelund CAST PIO. If before I have to pick between details (like VCap or Mundorf S/G/O) and sweet vocal (like Jensen or AudioNote), then I can bring those two worlds in Duelund (OMG, I’m losing my pocket!!!). The high tones are there, clearly defined, but on the same time, the it will never sound cold or excessive. Superb sweet vocal, superb speed in fast or attacking music, and superb detail. The only thing that I don’t like is its price 🙁

Please remember that this impression is from me and based on my own taste and equipment. Your opinion may be different and I completely respect it. And don’t forget, audio is an art, just like cooking or food tasting. Every one has their own taste. By using Duelund or VCap on your system won’t change a brick to a gold. Matching is the key. Remember, a good chef is the one who knows how to combined the food and ingredients into a good taste. By having an expensive food and expensive ingredients doesn’t guarantee you could be a good chef. But if you already a good chef, then combined with expensive food and expensive ingredients, you are definitely unbeatable!

I want to add some sites and forum related with Capacitor Comparison:

It’s enough for now. Prepare for the 2nd session with even higher spec equipment.