Volleyguy wrote: "It is those very Teflons that I am looking at... I am keeping the [Duelunds in the] speakers but am not sure about the amp."
When we ran most of the tests, the VSF was the only Duelund cap available and its size made it impractical to audition in our electronics. At some future time, I'd like to acquire small values of the newer Duelunds and see how they sound in active circuits, too.
"As far as for inductors would not foil resonate much more than wire if the insulation and structure could not hold the foil dead still?"
One would think that, but the proof is in the listening. That's why I always say keep an open mind and forget about preconceptions. Duelund abandoned the wire-wound, iron-core inductors in favor of foil, which they presumably think sounds better. Note that their foil inductors are highly damped and not loosely wound, though that's the way capacitors are fabricated, too. I'm referring back to Dave Slagle's argument that foil inductors that are built like capacitors should not sound as good as air-core, wire-wound inductors.
"Where the oil caps tested in a all oil circuit?"
We never tried that, but it's another variation that someone could explore.
"Steen did feel that he could hear plastic in the cap?"
That may be, but it never crossed our minds or came up as a topic for discussion. In other words, we never detected a "plastic" sound, just specific differences between different caps.
"I often wonder if SET movement has not been aided by the internet."
In the 1970s and 80s, when the commercial American audio scene evolved into acoustic suspension speakers driven by high powered solid state amps (like the Dyna 400, the Ampzilla, or the Phase Linears) and high-powered pentode amps (conrad-johnson and Audio Research), the SET movement was thriving in Japan. The Internet certainly accelerated the trend, though small journals like Sound Practices were important, too.
"Only in a non commercial enviroment can one find out that vintage Tannoy's can compete with speakers costing 50k."
What excites me about the Tannoy x-over project is that there is only one small value cap (about 1.5uF) directly in the signal path. This will open up a much wider range of candidates to test in speakers, including some of the silver foils which we just could not afford to purchase in a 10uF value. This should allow us to compare the various Duelunds, Audio Notes, Jensens, VCaps, REL Caps, and others, in a way that we were unable to do before.
Joe
