I have experience with the Duelund, V-cap, Mundorf and Sonicap in cross-over applications. I have tried using Mundorf and and V-cap in by-pass configuration for output caps on my preamp.
V-cap and Duelund are massive caps, and generally will not match the space constraints of an existing circuit. If you have a lot of extra space, or can otherwise accommodate them the V-cap is excellent (after about 600 hours!) The Duelund are further limited by their 100 volt design.
The Mundorf Silver in oil and Sonicap will generally be a much easier swap, and both are excellent caps. You will have no need to by-pass these cap, but I have found they make for an excellent by-pass caps .22uF or smaller for a large existing cap. This might be an option to explore.
Robert, I found the Duelund to be the most musical of the four. The V-cap is a great cap, and if you prefer an "audiophile" analytical sound, the V-cap may be more to your liking. I am not saying the V-cap is not natural or sounds electrical or non-musical, no not at all. They are a great cap, but I found over a few thousand hours of listening, and then swapping the Duelund/ V-Cap the Duelund was much more real and richly musical. I personally feel the Duelund is the best capacitor made, and I was very impressed with the people and dedication to the hobby; "very much like you and your passion for music."
The Mundorf Silver in oil is the best value, and if it lags behind the top two, it is not by much. The Mundorf gold in oil was a great disappointment. It tends to lack the bass definition and low end extension. This cap should only be considered as a .01uF by-pass cap in a system needing toning down on the top end, and in a system that will not suffer by losing a bit of bass.
The Sonicap might be considered the best high voltage cap of the group, but in a low voltage cross over the Duelund was my choice. I did not try the Sonicap in a high voltage location, but a friend has and it is very musical. Unfortunately I have not compared it with the Mundorf in a high voltage application so I can not add anything but my best guess. If I were looking into a high voltage application, I would look at the Sonicap and the Mundorf Silver in oil as the top brands. My guess is the Sonicap will be a bit more refined and a bit smoother, and a lot more expensive:-)
Please understand these comments are all relative, and the differences are very small. All four (or five with the gold) are amazing capacitors. The differences are in level of fine detail and/or musicality. In other words, musicality.
jd
Jade Audio, LLC
