George, to answer your question;
Here are just a couple of site quotes from fuse manufactures. Yes they obviously sell these, market these, based on delivering better sound. They don’t try to hide it and push better sound as the big benefit. This is not news?
This builder ( Audio Horizons) also puts the fuse in his amps and preamps touting better sound. No secret or hiding of what they feel is the big benefit. Fine sounding gear as an FYI.
"What Makes the Platinum Reference “More Than a Fuse" So Fine?
Without betraying proprietary information, let me note that the More Than a Fuse dramatically increases the impedance from 0.2 ohms to 10 ohms at 10 MHz, thus increasing high frequency noise-rejection fifty fold over that of a conventional fuse. As a result of this increased noise rejection, one can hear delicate extended high frequencies formerly swallowed up in noise."
"And because the Platinum Reference “More Than a Fuse” also reduces ultra high frequency noise by up to 46 dB or more, a ratio 200 times that of a typical fuse, high frequency harmonic texture is heard against a dead quiet background with a level of detail and refinement so sweet, delicate, and with such presence and immediacy—well, it will make you smile."
" Synergistic Research RED Fuses feature proprietary alloy burn wires and end caps encased in anti-resonant ceramic bodies. RED fuses are then treated with 2,000,000 volts of electricity in a process we call Quantum Tunneling that alters the conductor at a molecular level for optimum performance. Unique to SR RED Fuses is a new treatment process applied exclusively to SR RED Fuses that realigns the crystal structure of both the burn wire and the end caps for a refinement in high frequency characteristics and improved timbre linearity. All told SR RED fuses significantly outperform every other high-end fuse on the market and are the only fuses guaranteed to deliver a significant increase in system performance or your money back. When compared to our award winning SR20 Quantum Fuses, SR RED Fuses sound more refined with smoother highs and more linear frequency extension from the deepest bass to the highest highs; no small feat given the remarkable "
"Synergistic Research Quantum Fuses employ a custom alloy treated with 2,000,000 volts of electricity! SR Quantum Fuses significantly outperform all other high-end fuses on the market and are guaranteed to deliver a noticeable increase in sound staging, resolution and air thanks to a lower noise floor and blacker backgrounds. SR Quantum Fuses are available with a 30-day no risk money back guarantee so you can directly compare them to other high-end fuses on the market including Hi Fi Tuning Supreme, Furutech, and Audio Magic. With over 60 values to choose from, you’re sure to find the perfect value for your system’s components."