Capacitors tend to be the focus of much discussion amongst audio designers and the sea of "special" capacitors available appears limitless. The main reason for all this is that capacitors tend to be the least ideal of all the passive components and thus all tend to introduce their own character to the sound. The worst offenders are electrolytic types, with a huge range of others such as metalized film, film/foil, paper in oil etc also available. In valve circuits where coupling capacitors can have large dc potentials across them many of the highly regarded plastic film capacitors can sound a bit "hi- fi" and congested when compared to good paper in oil types, but even these sound diffuse and vague in comparison to Hovland Musicaps.
The best news we have for all home constructors or modifiers is our recent adoption of the Hovland Musicap range of polypropylene film and foil capacitors. These are far and away the best sounding plastic film caps we have ever heard. Maybe it is because they are the only ones to use a film and foil construction, where most of the other "audio" ranges only use a metalised polypropylene film. The Musicaps then use PTFE insulated silver plated copper lead, different colours at each end to aid correct orientation, and are very well made. The speaker range differs as a larger gauge of lead out wire is used, and obviously reaches higher capacitance values at lower voltages. The Hovland "sound" is fast, tight, dynamic, dramatic and clean. Non of the over bright aggressive treble of most polypropylenes, and non of the soggy bass or lumpy sonic characteristics of most plastic film caps. For the most up to date prices please consult the enclosed list. You may feel they are a little extravagant, but if your valve cost hundreds then why use cheap capacitors? We feel they are the best coupling method we have ever come across with the exception of our interstage transformers - this is the highest praise we can give. And there are obviously locations where even we need to use capacitors.
There are two ranges of Musicaps available. One range for coupling, priamrily in valve amplifiers, the other rnage for loudspeaker crossovers, or where lower voltage ratings are required. The current range of available units is:
Hovland Musicaps - Coupling Caps
Hovland Musicaps - Speaker Caps
Musicaps come fitted with colour coded leads for easy identification. The coupling caps have two inch leads with red as the inner foil, green as the outer. The red is normally connected to the input or high voltage side. The speaker caps have a blue line down the lead connected to the inner foil. This again is the input or amplifier end.
What the reviewers say......
"If you want see-thru, high definition detail and listenability, try the Musicaps" Joe Roberts, SOUND PRACTICES, Issue 6
"The improved signal transmission of the Hovland foil capacitors elevated the [Ariel] speakers to a new level of naturalness, clarity, and immediacy." Lynn Olson, POSITIVE FEEDBACK, Vol. 5, No. 4.
"So I yanked the Vitamin Qs and soldered in some Hovland MusiCaps I got in the mail. Immediate, radical, MAJOR change. The highs came out of hiding, images emerged from the fog, and it became possible to again discern detail." Seth Goldwin, SOUND PRACTICES, Issue 6.