"to never accept compromise"
- by founder Mr. Steen As. Duelund

Manufacturing by Duelund Coherent Audio, Denmark

Duelund CAST Capacitor
Duelund VSFcu PIO/cast 630V
"World's best capacitor"- Tested by Tony Gee - The Netherlands

The Duelund CAST Capacitor is our no holds barred flagship capacitor

The construction builds on the foundation of our Virtual Stack Foil design but does so with the addition of a proprietary WPIO dielectricum which necessitates several days of impregnation under high pressure.
This creates a form with incredible damping properties giving a mechanical stability hitherto unheard of. On top of this casting process, a ring of hard pressed paper strengthens the damping properties of the design helping music flow effortlessly.

The Duelund CAST capacitor is available for speaker use and as the CAST 630v for DC-applications. Available as pure copper or pure silver.
Standard sizes 0.01 uF - 50 uF other values available on request.

The Duelund CAST Capacitor is considered the world's best capacitor:
The CAST capacitor has all the same characteristics as the VSF but with added top-end clarity and together with that, more spatiality.
They are (like the VSF) super natural, smooth, clear and open. The tonal balance is extremely neutral, especially audible with good recordings of acoustic instruments and the human voice, so maily with classical music.

Like the VSF the separation of the individual instruments is very good and in an orchestra, the string section is a group of individuals rather than just a group.

Soprano's have clarity without becoming hard to the ear, wind instruments (especially the copper section) have that nice "metal" edge without becoming rough.
Where in the past you had to choose between a Mundorf Silver/Gold/Oil (very good depth and imaging) or a
Duelund VSF (very neutral presentation), you can now have the best of both worlds in the form of the Duelund CAST-Cu.
I did find they needed a couple of weeks use to fully come to bloom, so give a chance to burn-in. My current reference! So in other words: The king is dead, long live the king!

For further info: http://www.humblehomemadehifi.com/Cap.html


CAST-PIO-CU Case copper foil series
Pure foil high grade audio capacitor
600V, tol. +/- 10%,handmade in Denmark

Capacity (uF), Dim. in mm.

0.1 uf, 35 mm x 22mm x 26mm(H)
0.22 uf
0.47 uf
1 uf, 70 mm x 46mm x 45mm(H)
1.5 uf

CAST-PIO-CU Round pure copper foil
Pure foil high grade audio capacitor
630Vdc, tol. +/- 10%, handmade in Denmark

Capacity (uF), Dim. in mm.

0.22 uf, 46 mm dia. x 46mm(H)
0.47 uf, 46 mm dia. x 46mm(H)


CAST/PIO-CURound copper foil series
Pure foil high grade audio capacitor
100Vdc, tol. +/- 5%, handmade in Denmark

Capacity (uF), Dim. in mm.

1 uf, 72 mm dia. x 20mm(H)
2.2 uf
3.3 uf
3.9 uf
4.7 uf
5.6 uf
6.8 uf
10 uf

VSF Capacitor SQ. copper foil layer capacitor
VSF cap

VSF Capacitor:
The Virtual stack foil capacitor, a capacitor made specially for loudspeaker crossovers.

This new capacitor is the realization of a lifelong ambition. It consists of aluminium, copper or silver foil and high-density paper, soaked in pure mineral wax, treated with special lacquers made from natural materials and wrapped in paper. It is without question a "green" product.

The actual construction has been overseen by Mr. Steen Duelund Chief Engineer of Duelund Coherent Audio. Mr. Duelund has dictated the capacitor's special characteristics, i.e. its flatness, giving the opportunity to create its stack-foil working manner ensuring very low inductance, forming a solid block resulting in a form free of internal resonances. Furthermore, the flatness makes it easier to achieve greater values by connecting the capacitors in parallel.

The audiophile vocabulary contains many words that attempt to describe sonic qualities of equipment and components:
Immediacy, clarity, harmonic authenticity, detail, plasticity, uncolouredness etc.
While this capacitor has no problems fulfilling the promise of these words none of them encompass the sound that this component makes possible.

Only one word does this: Natural

The Duelund VSF capacitor is available for speaker use and as the VSF DC for DC-applications.

Standard sizes 0.01 uF - 50 uF other values available on request. .

VSF Cu Copper foil series
Capacity (uF), Dim. in mm.
0.1uf, 3 (thickness) x 35 x 45
0.47uf, 5 x 37 x 45
1uf, 10 x 41 x 45
2.2uf, 9 x 91 x 45
2.7uf, 11 x 93 x 45
3.3uf, 6 x 88 x 103
3.9uf, 8 x 89 x 103
4.3uf, 8 x 90 x 103
4.7uf, 9 x 90 x 103
5.1uf, 9 x 92 x 103
5.6uf, 10 x 92 x 103
6.8uf, 12 x 93 x 103
8.2uf, 15 x 96 x 103
10uf, 17 x 99 x 103
12uf, 22 x 104 x 103
15uf, 24 x 102 x 103
20uf, 31 x 113 x 103
24uf, 36 x 118 x 103
40uf, 53 x 135 x 103

VSF DC Cu copper foil DC series
Capacity (uF), Dim. in mm.
0.047uf, 4(thickness) x 21 x 45
0.1uf, 6 x 22 x 45
0.47uf, 15 x 30 x 45
1.0uf, 23 x 39 x 45
1.5uf, 31 x 47 x 45
2.2uf, 39 x 55 x 45

* Duelund Pure silver wire web page
Other value not listed on above, please contact

last updated on 11/18/12