Rerurn to Romy the Cat's Site
In the Forum: Melquiades Amplifier
In the Thread: Single-stage Melquiades vs. DHT amps
Post Subject: Mass ExtinctionPosted by Paul S on: 5/17/2009
fiogf49gjkf0d
Even if we all agree that the expensive film and foil or paper in oil caps are the best-sounding varieties available, there remains the problem of the inherent limitations of these types of caps. The paper in oils and the film and foils are not only physically large for a given value but they are also only available up to fairly small values at PS-type voltage ratings. Also, certain of their electrical characteristics are sub-optimal for high voltage use, anyway. The metalized film caps are physically smaller for a given value, and they are also available in larger values with higher voltage ratings; but not as high as electrolytics. Likewise, metalized film caps do not always look like the best choice for HV on paper, compared to electrolytics. Electrolytics, OTOH, are roundly beaten in terms of performance at low voltages, and especially in smaller values. This is why I do not use electrolytics for crossovers or coupling caps, etc; there are simply better-sounding caps available that are literally designed for these purposes.
Where MODERN electrolytics shine is specifically for PS use, for which use they have literally been optimized. I hear lots of talk about motor run caps for PS, but I have never heard a convincing demonstration. In fact, in my experience, at some point the gross physical mass of a cap seems to start working against it, sonically.
Something to keep in mind when using any cap is that some of the little suckers take EONS to break in. And until they do, HF is too "busy", LF is erratic, and clarity, harmonics and dynamics are compromised. Basically, a good cap that is not broken in sounds like a bad cap.
If to bypass a large-value electrolytic or metalized film, why not use a film and foil, if possible, to get the best of both worlds?
Best regards,
Paul SRerurn to Romy the Cat's Site